Journal articles on the topic 'Tadpoles'
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Taylor, Christopher N., Kerri L. Oseen, and Richard J. Wassersug. "On the behavioural response of Rana and Bufo tadpoles to echinostomatoid cercariae: implications to synergistic factors influencing trematode infections in anurans." Canadian Journal of Zoology 82, no. 5 (May 1, 2004): 701–6. http://dx.doi.org/10.1139/z04-037.
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We used high-speed videography of staged encounters between tadpoles of either Bufo americanus Holbrook, 1836 or Rana sylvatica LeConte, 1825 and Echinostoma Rudolphi, 1809 cercariae to understand why echinostomatoid trematodes, such as species from the genera Echinostoma and Ribeiroia Travassos, 1939 (implicated in anuran limb deformities), attack specific anatomical regions of tadpoles. Bufo and Rana tadpoles can shed cercariae on their skin from some parts of their body more easily than others. In particular, cercariae that enter the "dead-water zone" at the junction of a tadpole's body and tail appear particularly difficult for tadpoles to brush off. Cercariae that reach this recess can easily enter the inguinal region of tadpoles (as do Ribeiroia spp.) or ascend the tadpole's cloaca (as do Echinostoma spp.). When tadpoles sense cercariae contacting their skin they make explosive movements to shed those parasites. Factors that reduce tadpoles' activity, such as predator threat or certain pesticides, may increase a tadpole's susceptibility to echinostomatoid infection. Because Bufo tadpoles are unpalatable to many predators, they can afford to make more conspicuous evasive maneuvers than Rana tadpoles, and do so in the laboratory. Bufo tadpoles in the field also have a lower rate and different anatomical distribution pattern of Ribeiroia infection than Rana tadpoles. Factors that reduce tadpole activity in the field may act synergistically to increase parasite loads and subsequent deformities in anurans.
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Sushree Sangita Mohapatra and P. Arya Alok. "Niche occupancy and dietary profiling of Polypedates maculates tadpoles in temporary ponds of Northen Odisha." International Journal of Fundamental and Applied Sciences (IJFAS) 7, no. 3 (September 30, 2018): 51–67. http://dx.doi.org/10.59415/ijfas.v7i3.124.
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All living creatures, whether plants or animals depend on the food available in the system for nourishment and energy necessary for the completion of their life cycle. Feeding constituents are always been the important aspect of biology of tadpoles, which is the main target of this study. Available dietary resources in the ecosystem is especially important in tadpoles because they need to attend the early stage in very short-lived aquatic environments i.e. temporal ponds and tadpoles need to consume food that will ensure their metamorphosis prior to drying up the pond. Tadpoles of Polypedates maculatus were collected from temporary ponds of northern Odisha. The guts of tadpoles were dissected out and analysed for the qualitative and quantitative analysis of food consumed. Diet is basically composed of microalgae and relatively low amount of detritus. The algae belonging to class Chlorophyceae, Bacillariophyceae, Cyanophyceae and Euglenophyceae were recorded. The numeric frequency (NF%) and frequency of occurrence (FO%) of different food items show the species richness and abundance, which is consumed by tadpole. Huge diversity of algal flora as tadpole’s food items are determined by the two diversity indices i.e. Simposon and Shannon-Weiner. Niche breadth of the tadpole was analysed through Levin’s measure. The physicochemical parameters of water signifies the pollution free tadpole’s habitat, which the support the growth and metamorphosis of tadpoles. The diet preference and choice of algae as food indicates that the conservation of habitat in terms of algal diversity is essential for survival and completion of their life cycle of the tadpoles for successful survival of anurans.
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Baffico, Gustavo, and Carmen Úbeda. "Larval diet of the frog Alsodes gargola (Leptodactylidae: Telmatobiinae) and some ecological considerations on its role in alpine and mountain aquatic environments in Patagonia." Amphibia-Reptilia 27, no. 2 (2006): 161–68. http://dx.doi.org/10.1163/156853806777239986.
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AbstractAlsodes gargola is an endemic species from northwest Patagonia, Argentina. Its tadpoles inhabit oligotrophic high altitude lakes and mountain streams from their sources. Tadpole diet is an important yet still unknown feature of its biology. This study analyzes alimentary tract content from A. gargola tadpoles collected from several of the species' typical habitats. For each group of items eaten, frequency of occurrence and its importance in the diet according to biovolume was calculated. Tadpole feeding behavior was also observed. The most common items were periphyton and plant material. The predominant algae were diatoms (typically periphytic), chlorophytes (periphytic and some planktonic) and a few cyanobacteria. Planktonic components were found in low proportion in all samples. The animal component (mainly from periphyton) was represented by ciliates, flagellates and amoebae, and varied according to the habitats, as did vascular plant fragments. There was a wide size range of ingested particles (from 10 to 400 μm) and a wide variety of components, according to the features of each habitat. These results suggest that tadpole of A. gargola are grazers of the periphytic community and detritus gatherers. The larval diet matches the tadpole's morphological and structural adaptations to a lotic-benthic habitat (depressed body, ventral subterminal oral disc capable of adherence, dorsal eyes, low, subparallel fins) and direct observation of behavior in natural environments (slow-swimming bottom-dwelling tadpoles in still water or streams with slow-flowing microhabitats). We discuss the ecological role of slow-developing tadpoles (regulation of periphyton development), which attain large biomass in their particular ecosystems, where they are the only aquatic vertebrates.
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ORRICO, VICTOR GOYANNES DILL, MARCELLE MANTOANELLI MONGIN, and ANA MARIA PAULINO TELLES DE CARVALHO-E-SLIVA. "The tadpole of Hypsiboas latistriatus (Caramaschi & Cruz, 2004), a species of the Hypsiboas polytaenius (Cope, 1870) clade (Amphibia, Anura, Hylidae)." Zootaxa 1531, no. 1 (July 23, 2007): 25–37. http://dx.doi.org/10.11646/zootaxa.1531.1.2.
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Herein we describe the tadpole of Hypsiboas latistriatus from its type-locality and an adjacent, higher elevation pond. The tadpole is similar to the known tadpoles of other species of the H. pulchellus group. The tadpoles of H. latistriatus can be distinguished from other species group tadpoles by their oral formula [2(1,2)/ 3(1)] allied with a rounded lateral profile of the tail fins, instead of taper. The overall morphology is congruent with bentonic tadpoles. The tadpoles of H. latistriatus are usually found in Highland grass fields above 2000 m.a.s.l. in clear slow-flowing water bodies. Almost all tadpoles used in this study presented highly whitened mouthparts suggesting the presence of the fungal pathogen Batrachochytrium dendrobatidis.
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Pronych, Scott, and Richard Wassersug. "Lung use and development in Xenopus laevis tadpoles." Canadian Journal of Zoology 72, no. 4 (April 1, 1994): 738–43. http://dx.doi.org/10.1139/z94-099.
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Shortly after hatching, Xenopus laevis tadpoles fill their lungs with air. We examined the role played by early lung use in these organisms, since they are able to respire with both their lungs and their gills. We investigated the effect on X. laevis development when the larvae were prevented from inflating their lungs, and whether early lung use influenced the size of the lungs or the tadpole's ability to metamorphose. Tadpoles that were denied access to air had lungs one-half the size of those of controls. This difference in lung size was too large to be explained merely by a stretching of the lung due to inflation. The longer tadpoles were denied access to air, the longer they took to metamorphose, and their probability of completing metamorphosis diminished. One tadpole raised throughout its larval life without access to air successfully metamorphosed but had abnormal, solidified lungs and an enlarged heart. Collectively, these experiments demonstrate that early lung use in tadpoles is important in determining both ultimate lung size and the probability of successfully metamorphosing. Lung use during early larval development in X. laevis is not absolutely necessary for survival through metamorphosis, but its absence severely handicaps growth.
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Mogali, Santosh M., Bhagyashri A. Shanbhag, and Srinivas K. Saidapur. "Relative susceptibility of tadpoles of Uperodon taprobanicus (Anura: Microhylidae) and Duttaphrynus melanostictus (Anura: Bufonidae) to predacious Hoplobatrachus tigerinus (Anura: Dicroglossidae) tadpoles: significance of refugia and swimming speed in pre." Phyllomedusa: Journal of Herpetology 22, no. 2 (December 15, 2023): 139–46. http://dx.doi.org/10.11606/issn.2316-9079.v22i2p139-146.
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The relative susceptibility of two closely associated herbivorous tadpole species (Uperodon taprobanicus and Duttaphrynus melanostictus) to their natural carnivorous predatory tadpole, Hoplobatrachus tigerinus and the significance of refugia in predator avoidance was studied in the laboratory. In a total of 50 trials, 10 tadpoles each of U. taprobanicus and D. melanostictus of comparable sizes were exposed to starved H. tigerinus. Twenty-five trials included refugia while 25 did not. The results of this study showed that in both the presence and absence of refugia, D. melanostictus tadpoles fell prey to H. tigerinus more frequently than U. taprobanicus tadpoles. A key difference between the two prey species is the speed of swimming; Vmax of D. melanostictus (13.58 cm/s) tadpoles is significantly lower than that of U. taprobanicus (24.89 cm/s) tadpoles. This is likely to be the main reason why more D. melanostictus tadpoles were preyed upon than were U. taprobanicus tadpoles. It is important to note that the Vmax of the predator (60.21 cm/s) is much greater than those of the two prey species. However, predation risk of both prey tadpole species was affected significantly by the presence of refugia. The susceptibility of both prey tadpole species was lower where refugia were available. The present study clearly demonstrates that the more efficient avoidance of predation by U. taprobanicus tadpoles could be due to better use of refugia and their faster rate of movement.
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Figiel Jr., Chester R., and Raymond D. Semlitsch. "Effects of nonlethal injury and habitat complexity on predation in tadpole populations." Canadian Journal of Zoology 69, no. 4 (April 1, 1991): 830–34. http://dx.doi.org/10.1139/z91-125.
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Our purpose was to determine how nonlethal prey injury and habitat complexity mediate the dynamics of a predator–prey system. We assessed rates of predation by the crayfish Procambarus acutus acutus on Hyla chrysoscelis tadpoles with four levels of tail loss (0, 25, 50, and 75% total tail length removed), and in habitats of three levels of complexity (zero, low, and high density of screen) in a 4 × 3 factorial design. We also examined the effects of tail loss on tadpole sprint velocity and distance traveled. Tadpoles with 75% tail loss were preyed upon significantly more often than tadpoles in the other tail-loss treatments. Habitat complexity did not affect tadpole survival. In addition, there was no interaction between tail loss and habitat complexity. Tail loss significantly affected both tadpole swimming velocity and sprint distance traveled. Tadpoles with 75% tail loss had slower sprint speed and swam a shorter distance than tadpoles with 0 and 25% tail loss, and tadpoles with 50% tail loss had slower sprint speed and swam a shorter distance than tadpoles in the 0% tail loss treatment. Although tadpoles generally rely on short bursts of speed, generated by the tail, to escape predators, tail injury and apparently reduced swimming performance did not increase vulnerability to predation in a simple linear fashion.
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Mogali, Santosh M., Bhagyashri A. Shanbhag, and Srinivas K. Saidapur. "Comparative vulnerability of Indosylvirana temporalis and Clinotarsus curtipes (Anura: Ranidae) tadpoles to water scorpions: importance of refugia and swimming speed in predator avoidance." Phyllomedusa: Journal of Herpetology 20, no. 2 (December 21, 2021): 159–64. http://dx.doi.org/10.11606/issn.2316-9079.v20i2p159-164.
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The comparative vulnerability of two co-existing tadpole species (Indosylvirana temporalis and Clinotarsus curtipes) to their common predator, water scorpions (Laccotrephes sp.; Hemiptera: Nepidae), and the importance of refugia in predator avoidance were studied in the laboratory. In a total of 60 experimental trials, 10 tadpoles each of I. temporalis and C. curtipes of comparable body sizes were exposed to water scorpions (starved for 48 h). Thirty trials included refugia while 30 did not. The results of this study showed that in both the absence and the presence of refugia C. curtipes tadpoles fell prey to water scorpions more frequently than I. temporalis tadpoles. A main difference between the two species is the speed of swimming; Vmax of C. curtipes (24.73 cm/s) tadpoles is lower than that of I. temporalis (30.78 cm/s) tadpoles. This is likely to be the reason why more C. curtipes tadpoles were preyed upon than were I. temporalis tadpoles. Predation risk of tadpoles of both species was affected significantly by the presence of refuge sites. The vulnerability of both tadpole species was lower where refuge sites were available. The present study clearly shows that I. temporalis tadpoles avoid predation by water scorpions more effectively than do C. curtipes tadpoles.
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Mogali, Santosh M., Bhagyashri A. Shanbhag, and Srinivas K. Saidapur. "Sensory basis of food detection in tadpoles of Polypedates maculatus (Anura: Rhacophoridae): an experimental approach." Phyllomedusa: Journal of Herpetology 21, no. 1 (June 24, 2022): 59–65. http://dx.doi.org/10.11606/issn.2316-9079.v21i1p59-65.
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The mechanism of food detection in tadpoles of Polypedates maculatus was experimentally tested. We used a rectangular glass test tank with stimulus zones in opposite ends to provide visual and/or chemical food. For visual cues, boiled spinach was placed inside a glass container, and for chemical cues boiled spinach was placed in a mesh cage. Each tadpole of P. maculatus (either at an early or medium developmental stage) was held at the center of the test tank for acclimation. The tadpole was released, and we recorded whether it approached or did not approach the caged food. Tadpoles of all stages failed to detect food using visual cues. Tadpoles of all stages detected food using chemical cues. In tests using chemical cues, they spent the majority of their time (69.3% by early stage tadpoles and 87.3% by medium-stage tadpoles) near the container with food than in the end with no containers or with only visual food cues. Tadpoles in medium stages spent more time near food (18.1% of total time) than tadpoles in early stages. These findings indicate that tadpoles of P. maculatus detect food by chemical sensory mechanisms rather than visual ones. Tadpoles in medium stages spent more time near food than tadpoles in early stages indicating that time spent foraging increases as tadpoles grow.
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Kopp, K., M. Wachlevski, and P. C. Eterovick. "Environmental complexity reduces tadpole predation by water bugs." Canadian Journal of Zoology 84, no. 1 (January 1, 2006): 136–40. http://dx.doi.org/10.1139/z05-186.
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We assessed the role of habitat structure in the outcome of predation by measuring how aquatic vegetation influences predation rates of water bugs (Belostoma oxyurum (Dufour, 1863), Hemiptera, Belostomatidae) on tadpoles of Dendropsophus minutus (Peters, 1872) and Scinax curicica Pugliese, Pombal, and Sazima, 2004 (Anura, Hylidae). Considering that previous studies have shown that some tadpole species preferentially use microhabitats with aquatic vegetation at sites in southeastern Brazil, we hypothesized that these tadpoles may select such complex microhabitats because they can offer some protection against co-occurring predatory aquatic insects. We used field enclosures containing tadpoles of D. minutus and S. curicica and one predator (B. oxyurum), placed on natural substrata in sites both with and without aquatic vegetation, according to treatment. We measured the combined effects of predation and habitat structure on the survivorship of tadpoles, monitoring each enclosure daily during 10 days to survey surviving tadpoles. Treatments with predators reduced tadpole survivorship significantly in relation to controls for both tadpole species. The interaction between predator and vegetation was also significant, predation rates being lower when vegetation was present.
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Semlitsch, Raymond D. "Effects of body size, sibship, and tail injury on the susceptibility of tadpoles to dragonfly predation." Canadian Journal of Zoology 68, no. 5 (May 1, 1990): 1027–30. http://dx.doi.org/10.1139/z90-149.
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The effect of tadpole body size, sibship, and tail injury on the survival of treefrog tadpoles (Hyla chrysoscelis) in the presence of dragonfly larvae (Tramea lacerata) was examined in a three-way factorial experiment. Tadpole body size had a dramatic effect on survival; large tadpoles had higher survival than medium-sized or small tadpoles. The presence of tail injury simulating an unsuccessful predation attempt significantly reduced survival. Survival of control tadpoles without tail injury in the presence of a predator was almost twice as high as that of tadpoles with 75% tail loss. Tadpole sibship had no effect on survival and indicated that genetic differences in antipredator behavior or production of alarm substances and allelochemicals, independent of body size, were not apparent. There were no significant interactions between tail injury and body size or tail injury and sibship. These results indicate that increasing body size is an effective mechanism for reducing predation and that injury from an unsuccessful predation attempt reduces subsequent survival by increasing the risk of future predation.
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Marques, N. C. S., and F. Nomura. "Environmental and spatial factors affect the composition and morphology of tadpole assemblages." Canadian Journal of Zoology 96, no. 10 (October 2018): 1130–36. http://dx.doi.org/10.1139/cjz-2017-0313.
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Understanding how community compositions are affected by environmental and spatial factors are essential to provide knowledge about the distributions of species. Furthermore, these factors can play a role in species morphological variation. Tadpoles can be found in different types of aquatic microhabitats, showing a considerable amount of morphological diversity. We hypothesized that tadpole morphological diversity is controlled by ecological and spatial factors other than assemblage attributes, and that tadpole assemblage composition is affected by spatial factors. To test these hypotheses, we recorded the abundance of tadpoles from different ponds, identified eight environmental variables that represented local and landscape descriptors of the ponds, recorded the spatial coordinates of the ponds, and measured the morphological variation of assemblages. Spatial factors significantly affected the composition of tadpole assemblages, while both spatial and environmental factors affected morphological variation. The ability of tadpoles to alter their morphology in response to environmental factors might be a result of poor oviposition site choice, and this probably interacts with spatial factors to control the assemblage composition of tadpoles. Morphological variation is advantageous for tadpoles because it allows them to adjust their morphology to environmental conditions. This study has demonstrated how factors that control the assemblage composition of tadpoles also drive their morphological diversity.
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Wong, Adeline, Trevor J. C. Beebee, and Richard Griffiths. "The influence of tadpole size on cell-mediated competition between anuran larvae Bufo calamita and Rana temporaria) in the laboratory." Amphibia-Reptilia 21, no. 4 (2000): 431–38. http://dx.doi.org/10.1163/156853800300059322.
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AbstractThe faeces of tadpoles frequently contain cells that can inhibit the growth of other individuals. We examined the mechanism of such cell-mediated interference competition in interactions between tadpoles of Rana temporaria and Bufo calamita. When R. temporaria and B. calamita tadpoles were exposed to cell-laden faeces from larger R. temporaria tadpoles, growth was inhibited relative to controls. Tadpoles of B. calamita remained susceptible to the inhibitory effects of the cells for longer during development than those of R. temporaria. In the presence of excess food, cell production by both species was related to stage of development. Tadpoles raised with cell-laden faeces from R. temporaria tadpoles produced more cells/tadpole/hour than those raised without competitor faeces, and smaller tadpoles were more inhibited than larger tadpoles.
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Marques, N. C. S., L. Rattis, and F. Nomura. "Local environmental conditions affecting anuran tadpoles' microhabitat choice and morphological adaptation." Marine and Freshwater Research 70, no. 3 (2019): 395. http://dx.doi.org/10.1071/mf18106.
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In this study, we investigated the environmental variables that best explained tadpole occurrence, as well as associations between environmental variables and the morphological traits of tadpoles. We modelled the occurrence of tadpoles to evaluate the significance of trait–environment relationships by sampling in 86 ponds, measuring a set of environmental descriptors of these ponds, determining the tadpoles’ external-morphology changes and using a generalised linear mixed model approach. The best fitting model predicting tadpole occurrence included all the environmental variables measured (pond dimensions, pond margin type, pond bottom substrate, vegetation type inside the pond, vegetation type in the pond margins, landscape descriptors) and seven morphology–environment interactions. Tadpoles are capable of fine-tuning their morphology according to the environmental traits of the pond and land use changes around the pond. Vegetation heterogeneity of ponds interacts with tadpole morphology primarily on tail size and deviations in the mean position of the eye, nostril and mouth. Moreover, there are increases in body size and tail length in smaller ponds, as well as in ponds surrounded vegetation changes from forest to pasture or short crops. Changes in environmental variables as a result of land use change can affect the dispersion of adult frogs and, consequently, the occurrence of and morphological variations in tadpoles. Local environmental variables play important roles driving tadpoles’ microhabitat choice; once tadpoles cannot select the site of their developmental, they need to compensate for any mismatching by induced morphological adaptations.
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Jara, Fabián Gastón. "Differential vulnerability of Physalaemus pustulosus tadpole size classes to predation by the water spider Thaumasia sp. (Physauridae)." Amphibia-Reptilia 29, no. 3 (2008): 432–37. http://dx.doi.org/10.1163/156853808785111977.
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Abstract The effect of predatory water spiders on the tadpole size-structure is poorly understood. Here I present a study of the effect of the spider Thaumasia sp. on the survivorship of Physalaemus pustulosus tadpoles in a tropical system. Under experimental conditions, tadpoles of one or two sizes were offered to juvenile spiders. Two experiments were conducted, one during the day and another during the night. The spiders consumed a greater number of large tadpoles in all treatments, and more tadpoles of both sizes were eaten during the day. This suggests that larger tadpoles are more susceptible to predation by Thaumasia sp. and that tadpoles are more vulnerable during the day.
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RODRIGUES, DOMINGOS J., MARCELO MENIN, and ALBERTINA P. LIMA. "Redescription of the tadpole of Leptodactylus rhodomystax (Anura: Leptodactylidae) with natural history notes." Zootaxa 1509, no. 1 (June 18, 2007): 61–67. http://dx.doi.org/10.11646/zootaxa.1509.1.6.
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The tadpole of Leptodactylus rhodomystax is described based on individuals in several stages of development. We compare them with other tadpoles of the Leptodactylus pentadactylus group and three other sympatric species with similar morphology and color patterns. We also provide comments on spawning sites, clutch size, and the distribution of tadpoles in ponds located in a 64 km 2 study area. The tadpole of L. rhodomystax differs from all species of the L. pentadactylus group (except L. flavopictus) in total length and in having uniform black color. It differs in relation to the LTRF (2(2)/3) of all species except L. lithonaetes and L. rhodonotus. Leptodactylus rhodomystax is generally only found in the western watershed of our study area. Foam nests were deposited between shrubs, roots, and fallen tree trunks near temporary ponds. Tadpoles were free-swimming, benthic, and found in the leaf litter of ponds between January and May. The tadpoles are intraand inter-specific predators of anuran eggs and tadpoles.
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VIEIRA, WASHINGTON LUIZ DA SILVA, GINDOMAR GOMES SANTANA, and KLEBER DA SILVA VIEIRA. "Description of the tadpole of Leptodactylus vastus (Anura: Leptodactylidae)." Zootaxa 1529, no. 1 (July 19, 2007): 61–68. http://dx.doi.org/10.11646/zootaxa.1529.1.5.
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The Neotropical frog Leptodactylus vastus belongs to the L. pentadactylus group, a group that currently contains 14 species, and of which nine tadpoles have been described. The tadpoles of L. vastus described here are generally much smaller than tadpoles of the other species described. The oral disk of L. vastus tadpoles is almost anteriorly placed, similar to other tadpoles in the group except for L. lithonaetes and L. rugosus, and the rows of marginal papillae in L. vastus are different from those in the other species. The tadpoles of L. vastus have a 1/2(1) LTRF similar to that of L. labyrinthicus and amazonian L. pentadactylus, whereas other species in the group show different arrangements of the tooth rows. The internal oral characteristics of the tadpole of L. vastus differs from L. knudseni and L. pentadactylus by having four infralabial papillae, possess 4–5 prepocket papillae surrounded by postulations and the buccal roof arena is circular, surrounded by two long papillae and 4–6 smaller papillae. The tadpoles of L. vastus, in general, possess a set of morphological characteristics that are very similar to those of other species of the L. pentadactylus group, and some of them are probably related to tadpole ecology.
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Rautio, Sarah A., Elizabeth A. Bura, Keith A. Berven, and George J. Gamboa. "Kin recognition in wood frog tadpoles (Rana sylvatica): factors affecting spatial proximity to siblings." Canadian Journal of Zoology 69, no. 10 (October 1, 1991): 2569–71. http://dx.doi.org/10.1139/z91-362.
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In blind laboratory observations, we investigated three factors affecting spatial proximity to full siblings in wood frog (Rana sylvatica) tadpoles. In the first set of observations, we provided tadpoles the opportunity to associate with (i) siblings or no larvae and (ii) nonkin or no larvae. Tadpoles associated preferentially with siblings over no larvae, but showed no preference for either nonkin or no larvae. Thus tadpoles associate with siblings because they are attracted to kin rather than repulsed by nonkin. In a second set of observations, 10-day-old tadpoles failed to display sibling recognition, while 17-day-old tadpoles displayed a significant sibling preference. Furthermore, 17-day-old tadpoles spent significantly more time with siblings than did 10-day-old tadpoles. Thus, age affects sibling preference in wood frog tadpoles. When retested several days later, the former 17-day-old tadpoles again displayed a significant kin preference. However, there was no significant correlation in kin preference between a tadpole's first and second test. This and another comparison indicate that all wood frog tadpoles possess recognition ability, and that the failure of some tadpoles to manifest sibling preference is not due to a lack of recognition ability.
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Gazzola, Andrea, Bianca Guadin, Alessandro Balestrieri, and Daniele Pellitteri-Rosa. "Multimodal Cues Do Not Improve Predator Recognition in Green Toad Tadpoles." Animals 12, no. 19 (September 28, 2022): 2603. http://dx.doi.org/10.3390/ani12192603.
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The anti-predator behaviour of green toad (Bufotes balearicus) tadpoles was investigated by exposing them to only the visual or chemical cues, or a combination of both, of a native predator, southern hawker Aeshna cyanea. We collected green toad egg strings in the field and tadpoles did not receive any predatory stimulus before the onset of the experiment. To manipulate chemical and visual cues independently, dragonfly larvae were caged inside a transparent plastic container, while chemical cues (odour of tadpole-fed dragonfly larvae) were injected into the surrounding arena. An empty container and water were used, respectively, as controls. The behaviour of individually tested tadpoles was videorecorded for 40 min, of which 20 were before their exposure to stimuli. Five second-distance frames were compared to assess both tadpole activity and position within the arena with respect to the visual stimulus. The tadpole level of activity strongly decreased after exposure to either chemical cues alone or in combination with visual cues, while visual cues alone apparently did not elicit any defensive response. The position of tadpoles inside the arena was not affected by visual cues, suggesting that green toad tadpoles mainly rely on olfactory cues to assess the level of predation risk.
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von May, Rudolf, Margarita Medina-Müller, Maureen A. Donnelly, and Kyle Summers. "Breeding-site selection by the poison frog Ranitomeya biolat in Amazonian bamboo forests: an experimental approach." Canadian Journal of Zoology 87, no. 5 (May 2009): 453–64. http://dx.doi.org/10.1139/z09-026.
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Habitat selection in amphibians has typically been investigated using species that breed in medium-sized to large bodies of water. So far, few studies have focused on tropical, phytotelm-breeding species. We examined habitat selection in the context of reproductive resource use by Ranitomeya biolat (Morales, 1992), a poison frog that uses bamboo internodes as breeding sites. We conducted field observations and experiments using bamboo and PVC sections to test the effect of physical and biotic factors on tadpole deposition. Our field observations indicated that water volume, as well as internode length, height, and angle, may be important for tadpole deposition. We predicted that adult R. biolat would deposit tadpoles in pools that are close to the ground, pools with high water volume, pools contained in long structures, and pools without conspecific tadpoles or heterospecific predators. Our experiments demonstrated that water volume and the length of the structure containing the pool affect the pattern of tadpole deposition. Tadpoles were also deposited more frequently in experimental pools containing no other tadpoles or no predators. Our results support the prediction that phytotelm-breeding species, to maximize their reproductive success, should deposit their tadpoles in pools with water volumes that maximize nutrient content and that present no competitors or predators.
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Cabral Eterovick, Paula, and Isalita Souza Barros. "Niche occupancy in south-eastern Brazilian tadpole communities in montane-meadow streams." Journal of Tropical Ecology 19, no. 4 (July 2003): 439–48. http://dx.doi.org/10.1017/s026646740300347x.
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Microhabitat use by tadpole species was investigated in streams of montane meadows of the Serra do Cipó, south-eastern Brazil. Microhabitats were classified into 24 types based on water depth, current, aquatic vegetation and substrate type, and quantified in 16 streams. A total of 844 tadpoles from 19 species was recorded, as well as microhabitat types used. Tadpoles, from all species pooled, used microhabitat types in the proportions available in the set of sampled streams. Diversity of microhabitats used was considered as a measure of niche breadth for tadpoles, and microhabitat diversity in streams was interpreted as available niche space. For the most part, species used microhabitats in different proportions, and conspecifics differed in microhabitat use among different streams. Neither niche breadths nor niche overlaps of tadpoles could be related to the number of species occupying streams. Thus not all available niche space may be occupied by tadpole species. More generalist species (those with broader niches) did not generally occupy more streams. Behavioural flexibility of tadpoles in microhabitat use may be a response to the unpredictability of the montane-meadow stream habitat. The role of adult anurans in choosing oviposition sites may also influence the distribution of tadpole species among streams.
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Smilansky, Vanessa, Miloslav Jirků, David S. Milner, Roberto Ibáñez, Brian Gratwicke, Andrew Nicholls, Julius Lukeš, Aurélie Chambouvet, and Thomas A. Richards. "Expanded host and geographic range of tadpole associations with the Severe Perkinsea Infection group." Biology Letters 17, no. 6 (June 2021): 20210166. http://dx.doi.org/10.1098/rsbl.2021.0166.
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Severe Perkinsea infection is an emerging disease of amphibians, specifically tadpoles. Disease presentation correlates with liver infections of a subclade of Perkinsea (Alveolata) protists, named Pathogenic Perkinsea Clade (PPC). Tadpole mortality events associated with PPC infections have been reported across North America, from Alaska to Florida. Here, we investigate the geographic and host range of PPC associations in seemingly healthy tadpoles sampled from Panama, a biogeographic provenance critically affected by amphibian decline. To complement this work, we also investigate a mortality event among Hyla arborea tadpoles in captive-bred UK specimens. PPC SSU rDNA was detected in 10 of 81 Panama tadpoles tested, and H. arborea tadpoles from the UK. Phylogenies of the Perkinsea SSU rDNA sequences demonstrate they are highly similar to PPC sequences sampled from mortality events in the USA, and phylogenetic analysis of tadpole mitochondrial SSU rDNA demonstrates, for the first time, PPC associations in diverse hylids. These data provide further understanding of the biogeography and host range of this putative pathogenic group, factors likely to be important for conservation planning.
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Silva, WR, and AA Giaretta. "Further notes on the natural history of the South American pepper frog, Leptodactylus labyrinthicus (Spix, 1824) (Anura, Leptodactylidae)." Brazilian Journal of Biology 68, no. 2 (May 2008): 403–7. http://dx.doi.org/10.1590/s1519-69842008000200024.
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Leptodactylus labyrinthicus tadpoles reach a large size in the nest through consumption of trophic eggs. We previously suggested that the trophic eggs are laid just after amplexus has finished, but our new data do not support this hypothesis. We also present further details on the natural history of the species with regard to breeding activity, spawning site, retreats and the ability of tadpoles in preying upon fully-growth heterospecific tadpoles. We also show that the tadpoles are mainly nocturnal and take diurnal refuges. We collected the data in Brazil in three localities within the Cerrado Biome. We examined burrows used by L. labyrinthicus males, verified if females still contained mature eggs just after released from amplexus, and tested the ability of tadpoles in preying fully-growth heterospecific tadpoles. Field observations and experiments were conducted on tadpole activity time, hiding behaviour and level of susceptibility to predation by the bird leaf-scrapers in four sheltering situations. Reproduction could start before the first rains; this may be advantageous by allowing the tadpoles to exploit eggs of other frogs. We found one floating nest built in a temporary pool. The nest of the species is normally circumscribed in an excavated basin beside the water body. Adult males were found during the day with their head-out of the entrance of underwater burrows, which were perforations through dense root mats beside calling/spawning sites. Probably, these burrows in permanently water-filled soil are actively excavated by males. Females released all their eggs during the amplexus, so trophic eggs are not produced by the currently-accepted mechanism. Fully-grown heterospecific tadpoles were not preyed upon by L. labyrinthicus tadpoles, which can prey only slow-moving newly hatched ones. Field tadpoles took shelter under mud/dead leaves during daylight and became exposed on the bottom at night. Free-ranging leaf-scrapers removed dead leaves from a pool with their beaks and preyed upon tadpoles. In the experiments, the tadpoles sheltered under gravel/leaves during daylight, but they were exposed at night. Leaf-scrapers ate all exposed tadpoles, but no tadpole of the gravel/leaves trays was consumed. Hence the nocturnal habits and use of diurnal refuges may protect the tadpoles from visual predators, such as the leaf-scrapers.
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Iwai, N. "Estimating tadpole-detection rates using visual field surveys: effects of survey time, tadpole species and tadpole density." Wildlife Research 44, no. 2 (2017): 147. http://dx.doi.org/10.1071/wr16147.
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Context When understanding species occupancy, estimation of detection probability for the target species is often required, provided by repeated surveys. However, if the actual detection probability of the species is determined experimentally, such estimates are not required, and the reliability of the occupancy data obtained by a particular survey effort can be determined. Aims The aim of this study was to determine the detection rate of tadpoles using visual field surveys, as well as to explore the effects of survey time, species and tadpole density on the tadpole-detection rate. The suitability of visual surveys for detecting tadpole occupancy was also assessed. Methods Batch-identified tadpoles were released into several pools and repeatedly counted over successive days to calculate detection rates using visual observation. In Experiment 1, the effects of tag colour, survey time (morning vs night) and species on the detection rates of two species of tadpoles (Babina subaspera and Odorrana splendida) were examined. In Experiment 2, the effects of tadpole density on O. splendida were examined. Key results Detection rates varied by survey time, species and tadpole density; mean rates ranged from 0.2 to 0.6 for B. subaspera and 0.4 to 0.8 for O. splendida, with higher rates at night. There was a negative relationship between detection rate and tadpole density. Based on these detection rates, it was calculated that single visual surveys of O. splendida tadpoles can achieve detection probabilities near 1.0 when more than four individuals occur in a patch. Conclusions Variations in detection probability should be considered in field surveys. If the factors that cause variations in detection rates are controlled, visual surveys of tadpoles should, at least in some species, provide detection probabilities near 1.0. Implications When repeated surveys to estimate species occupancy are not practicable, determination of the actual detection probability of the target species using real detection rates provides a robust alternative approach.
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Liu, H., R. Wassersug, and K. Kawachi. "The three-dimensional hydrodynamics of tadpole locomotion." Journal of Experimental Biology 200, no. 22 (November 1, 1997): 2807–19. http://dx.doi.org/10.1242/jeb.200.22.2807.
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Tadpoles are unusual among vertebrates in having a globose body with a laterally compressed tail abruptly appended to it. Compared with most teleost fishes, tadpoles swim awkwardly, with waves of relatively high amplitude at both the snout and tail tip. In the present study, we analyze tadpole propulsion using a three-dimensional (3D) computational fluid dynamic (CFD) model of undulatory locomotion that simulates viscous and unsteady flow around an oscillating body of arbitrary 3D geometry. We first confirm results from a previous two-dimensional (2D) study, which suggested that the characteristic shape of tadpoles was closely matched to their unusual kinematics. Specifically, our 3D results reveal that the shape and kinematics of tadpoles collectively produce a small 'dead water' zone between the head-body and tail during swimming precisely where tadpoles can and do grow hind limbs--without those limbs obstructing flow. We next use our CFD model to show that 3D hydrodynamic effects (cross flows) are largely constrained to a small region along the edge of the tail fin. Although this 3D study confirms most of the results of the 2D study, it shows that propulsive (Froude) efficiency for tadpoles is overall lower than predicted from a 2D analysis. This low efficiency is not, however, a result of the high-amplitude undulations of the tadpole. This was demonstrated by forcing our 'virtual' tadpole to swim with fish-like kinematics, i.e. with lower-amplitude propulsive waves. That particular simulation yielded a much lower Froude efficiency, confirming that the large-amplitude lateral oscillations of the tadpole do, indeed, provide positive thrust. This, we believe, is the first time that the unsteady flow generated by an undulating vertebrate has been realistically modelled in three dimensions. Our study demonstrates the feasibility of using 3D CFD methods to model the locomotion of other undulatory organisms.
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SILVA-SOARES, THIAGO, PAULO NOGUEIRA COSTA, RODRIGO B. FERREIRA, and LUIZ NORBERTO WEBER. "The tadpole of the hylid frog Scinax belloni (Anura: Hylidae)." Zootaxa 2727, no. 1 (January 23, 2019): 63. http://dx.doi.org/10.11646/zootaxa.2727.1.6.
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Scinax perpusillus group is composed by11 species. Only Scinax arduous, Scinax littoreus, Scinax. meloi, S. perpusillus, S. tupinamba, and S. v-signatus, have its tadpole described. Herein we described the tadpole of Scinax belloni and its internal oral features. Tadpoles of S. belloni were collected in bromeliads at the Parque Estadual do Forno Grande, municipality of Castelo, Espírito Santo, southeastern. Two tadpoles were reared to froglets in order to allow specific identification. The morphology of S. belloni tadpoles resemble the other known larvae in many aspects such as oval body in dorsal view, coloration, rounded snout in dorsal view, dorsolateral eyes, anteroventral mouth and labial tooth row formula 2(2)/3. In fact, at first sight, all known tadpoles are very similar from each other. Nevertheless, they do can be distinguished by some characters as the shape of lower jaw; number of row of labial papillae; the size of the fins; height of tail and the body; whether musculature of tail reaches its tip and if tail ends rounded or pointed. S. belloni tadpoles are readily differentiated from the other known Scinax gr. perpusillus species tadpoles by the presence of a dark band that goes along the dorsal and ventral fin. The internal oral morphology of S. belloni is also described.
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Donald, David B., William T. Aitken, Carrie Paquette, and Shaun S. Wulff. "Winter snowfall determines the occupancy of northern prairie wetlands by tadpoles of the Wood Frog (Lithobates sylvaticus)." Canadian Journal of Zoology 89, no. 11 (November 2011): 1063–73. http://dx.doi.org/10.1139/z11-082.
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In the northern plains of North America, the wetland breeding habitat of amphibians and their populations could be reduced by a change in climate that included decreased precipitation. To test this hypothesis, relative abundance of late-stage tadpoles of the Wood Frog ( Lithobates sylvaticus (LeConte, 1825)) was monitored from 1997 to 2010 during a wet–dry–wet cycle in 29 wetlands distributed throughout central Saskatchewan, Canada. The wetlands were dry for up to 7 consecutive years, and for a mean of 3.8 consecutive years. Consequently, tadpole occupancy of the wetlands was reduced to less than 40% for 5 consecutive years and none of the wetlands had tadpoles during the severe drought of 2001 and 2002. However, the drought had no observable long-term effect on either tadpole occupancy of wetlands or tadpole abundance. In 2007, 93% of the wetlands supported tadpoles, and in 2008 the highest mean relative abundance of tadpoles was recorded. Tadpole occupancy of wetlands was related to winter and spring precipitation (R2 = 0.84) with 67% of long-term variation in occupancy related to snowfall from November to February and 17% related to rainfall from March to June. Less than 45 mm of winter precipitation for 6 consecutive years would probably cause regional extinction of populations of the Wood Frog.
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Smith, Geoffrey R., Jessica E. Rettig, Mallory Smyk, Maggie Jones, Genevieve Eng-Surowiec, Davit Mirshavili, and Jeremy Hollis. "Consumption of the eggs, hatchlings, and tadpoles of Green Frogs (Lithobates clamitans) by native and non-native predators." Amphibia-Reptilia 40, no. 3 (2019): 383–87. http://dx.doi.org/10.1163/15685381-20181071.
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Abstract Predation by native and non-native predators on the eggs, embryos, and early stage tadpoles can affect the recruitment of offspring into a population. We examined the effects of native (Little Brown Mudbugs, Cambarus thomai; overwintered Rana tadpoles; Common Green Darner, Anax junius, larvae) and non-native (Western Mosquitofish, Gambusia affinis) potential predators on the eggs, hatchlings, and early tadpoles of the Green Frog (Lithobates clamitans). The predators had no effect on survivorship or hatching of L. clamitans eggs. However, tadpole survivorship was significantly reduced by dragonfly larvae and crayfish, but not G. affinis or the overwintered ranid tadpoles. Our observation that invertebrates consumed Green Frog tadpoles while vertebrates did not is consistent with palatability contributing to the tadpoles’ susceptibility to different predators. Our results therefore suggest Green Frog tadpoles, but not eggs or embryos, from some populations may be subject to differential predation by invertebrate and vertebrate predators.
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Julien, A. R., S. B. Park, C. K. Vance, P. L. Ryan, S. T. Willard, A. J. Kouba, and J. M. Feugang. "116 INCORPORATION AND DEVELOPMENTAL TOXICITY OF QUANTUM DOT NANOPARTICLES IN AMPHIBIAN LARVAE." Reproduction, Fertility and Development 29, no. 1 (2017): 166. http://dx.doi.org/10.1071/rdv29n1ab116.
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The use of nanoparticles both commercially and pharmaceutically has increased over the past decade, including fluorescent quantum dot nanoparticles (QD) in biochemical research for in vivo imaging. Previous studies have reported the toxic effects of nanoparticles, but their effects on larval metamorphosis and animal development and growth have not been thoroughly examined. Additionally, the method of uptake of nanoparticles by larval systems is unknown. Amphibian larvae are an ideal model for assessing toxicity because of their sensitivity to environmental contaminants and rapid and easily observable developmental stages. We used Anaxyrus fowleri tadpoles to investigate QD (≤ 25 nm diameter) integration into larvae and possible deleterious effects on their growth and development. Tadpoles (A. fowleri; n = 5/group) were placed in 24-well plates containing 1 mL of distilled water and increasing concentrations of QD (0, 1, and 2 nM) 72 h post-hatch. The fluorescence emission of QD in wells was detected at various time points (1, 2, 24, 48, and 72 h) using the in vivo imaging system (IVIS). A subset of tadpoles was killed (MS-222) and sectioned for histopathology. Remaining tadpoles were monitored throughout development. Fluorescence emission of QD in sectioned tadpoles was visualised using an EVOS Cell Imaging System. Developmental metrics of living tadpoles were recorded until metamorphosis. Fluorescence intensity between controls and dosage groups were analysed by ANOVA-1, followed by Student’s l.s.d. test to evaluate the effects of QD concentration and exposure time. The threshold of significance was P < 0.05. The rate of incorporation of QD into tadpoles was determined using the equation y = C + Ao*2(–x/t1/2), where t1/2 is the half-life of QD remaining in solution. The IVIS imaging revealed a rapid decrease of QD fluorescence (total flux) signals from the aqueous tadpole environment. Decreases in fluorescence occurred within 1 h post-exposure and appeared dose and time dependent, with signal nearly gone within 48 h. Half-life of total flux (time necessary for tadpoles to absorb half of the QD in solution) is 20.75 h (R2 = 0.92) and 2.54 h (R2 = 0.96) for 1 nm and 2 nm QD in solution, respectively. The EVOS imaging revealed integration of QD and localization into tadpole tissues. Fluorescence was exclusively found within the mouth, gills, and sections of the intestinal lumen of exposed tadpoles within the first hour. Dose-dependent increases in fluorescence within tissue were observed at each time-point. No signal was observed in controls. In remaining live tadpoles, QD treated tadpoles were smaller in size [t(34) = 2.35, P = 0.024] than controls. Findings reveal that (1) A. fowleri tadpoles integrate and accumulate nanoparticles, without detectable excretion within 72 h post-exposure, and (2) nanoparticles impede normal tadpole development. Ongoing studies are determining the effects of QD exposure on complete tadpole metamorphosis. The work was supported by USDA-ARS Biophotonics Initiative grant #58–6402–3-018.
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Da Silva Gonçalves, Brena, Carla D. Hendges, Bruno Madalozzo, and Tiago G. Santos. "Re-description of external morphology and factors affecting body and tail shape of the stone frog tadpoles." Acta Herpetologica 17, no. 1 (May 14, 2022): 59–70. http://dx.doi.org/10.36253/a_h-11315.
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Ecological studies testing the preponderance of environmental filters on ontogeny to explain the variation in tadpole morphology are scarce for Neotropical anurans. We used tadpoles of the stone frog Limnomedusa macroglossa (Alsodidae): (1) to assess the variation in body and tail shape; (2) to examine the effect of streamlet depth and allometry on tadpole shape, and (3) to re-describe and compare the tadpole external morphology with closely related species. We obtained the body shape and size from 150 tadpoles. The re-description was based on 57 qualitative and 24 quantitative characters, from 19 tadpoles between stages 30 and 37 and 31 to 37, respectively. Allometry was the major factor influencing the lateral view of body shape: smaller tadpoles had round bodies and eyes and nostrils positioned more laterally in comparison with larger ones. Thus, the power of ontogenetic variations reported here makes the tadpole developmental “climax” period a questionable concept that deserves additional attention. The depth gradient of streamlets also affected the shape: in shallower environments, the tadpoles presented a decrease in height of the body, fins and tail muscles, and an increase in body width. These results may indicate adaptations allowing better swimming performance in lotic environments with intense water flow. The external morphological characterization of L. macroglossa presented here differed from that previously reported, mainly due to coloration, body shape, nostril, anal tube, tail, shape and position of nostrils and snout. Additionally, we presented unknown traits for this species, making comparisons with closely related species within the Alsodidae family.
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Xiaoqin, Zhang, Zhao Changju, and Wu Haoyang. "Toxicity of Cypermethrin-chlorpyrifos and Butachlor to Tadpole of Quasipaa boulengeri." E3S Web of Conferences 293 (2021): 01012. http://dx.doi.org/10.1051/e3sconf/202129301012.
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The tadpole of Quasipaa boulangeri was taken as the research object in this paper. The toxic effects of cypermethrin-chlorpyrifos and butachlor on tadpole of Q.boulangeri were studied by acute toxicity experiment and subchronic toxicity experiment in order to master the toxicity of different types of pesticides on tadpole of Q.boulangeri and provide scientific basis for amphibian protection. The results of acute toxicity experiment were analyzed by the method of probability unit regression analysis. The results of the acute toxicity experiment were analyzed by means of the probability-unit regression analysis method, and the LC50 of cypermethrin-chlorpyrifos and butachlor to the 2-month-old frog tadpoles at 24h, 48h, 72h and 96h were 0.419, 0.357, 0.346L, 0.332 and 1.183, 1.108, 0.925 and 0.876(mg/L), respectively. In the subchronic toxicity experiment, we observed the accumulation effect of different concentrations of pesticides on tadpoles through the statistics of the growth and development of tadpoles exposed to the drugs for a long time. The results suggested that the body length and body weight of tadpoles increased slowly with the increase of time and concentration of pesticide in the solution during the experiment.
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Sazima, Ivan, and Paula Eterovick. "Description of the tadpole of Leptodactylus syphax, with a comparison of morphological and ecological characters of tadpoles and adults of the species in the L. pentadactylus group (Leptodactylidae, Anura)." Amphibia-Reptilia 21, no. 3 (2000): 341–50. http://dx.doi.org/10.1163/156853800507534.
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AbstractLeptodactylus syphax belongs to the L. pentadactylus group, one of five species groups defined for the genus. The tadpole of L. syphax develops in lotic habitats, as do the tadpoles of L. lithonaetes and L. rugosus. The tadpole of L. syphax is here described and differs from the tadpole of L. rugosus by having a less flattened and larger body, from the tadpole of L. lithonaetes by having a larger body in relation to total length and a larger oral disc in relation to body length. Further, it differs from the tadpole of L. rhodomystax by its color, body shape in dorsal profile and mouth shape, and from the tadpole of L. rhodonotus by its body shape in dorsal profile and spiracle position. A cluster analysis of several morphological and ecological features of adults and tadpoles from the species of the L. pentadactylus group grouped L. syphax with L. rhodomystax and L. rhodonotus, species with chest spines, moderate body size, relatively small head, unbarred lips, tadpoles with five tooth rows and aquatic development. The remaining species of the L. pentadactylus group were distributed among four additional clusters.
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Griesbaum, Frederic, Mareike Hirschfeld, Michael F. Barej, Andreas Schmitz, Mariam Rohrmoser, Matthias Dahmen, Fabian Mühlberger, et al. "Tadpoles of three western African frog genera: Astylosternus Werner, 1898, Nyctibates Boulenger, 1904, and Scotobleps Boulenger, 1900 (Amphibia, Anura, Arthroleptidae)." Zoosystematics and Evolution 95, no. 1 (April 5, 2019): 133–60. http://dx.doi.org/10.3897/zse.95.32793.
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Herein, we describe the tadpoles of six Astylosternus species, A.fallax, A.cf.fallax, A.laurenti, A.montanus, A.perreti, A.ranoides, and Scotoblepsgabonicus, and redescribe the tadpoles of A.batesi, A.diadematus, A.laticephalus, A.occidentalis, A.rheophilus, and Nyctibatescorrugatus. All Astylosternus tadpoles are adapted to torrent currents and share a long, oval body, slightly flattened in lateral view, with very long muscular tails with narrow fins. The jaws are massive, serrated, and often show a tooth-like medial projection (fang) in the upper jaw. Body proportions of Astylosternus tadpoles are extremely similar. The best characters to distinguish species might be life coloration and potentially the shape of labial papillae. The tadpole of Scotoblepsgabonicus is similar to Astylosternus and differs only slightly by a narrower body with a shorter and rounder head. The upper jaw of Scotobleps carries two or three lateral fangs instead of one medial one. The tadpole of Nyctibatescorrugatus is easily distinguishable from the other two genera on the basis of their very long, eel-shaped body and tail and the bluish-black color.
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Rödel, Mark-Oliver. "Predation on tadpoles by hatchlings of the freshwater turtle." Amphibia-Reptilia 20, no. 2 (1999): 173–83. http://dx.doi.org/10.1163/156853899x00187.
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AbstractExperiments with Pelomedusa subrufa, a widespread African freshwater turtle, showed that this species consumed large quantities of tadpoles. Tadpoles preyed upon, comprised between 0.05 and 21.55% of the turtle's biomass. This demonstrated that Pelomedusa subrufa was neither gape limited nor did it ignore very small prey. Tadpoles with an ovoid body shape (Hemisus marmoratus, Hyperolius nitidulus, Ptychadena maccarthyensis), which shared, under natural conditions, the pond bottom microhabitat with the turtles, were more threatened than the robust tall-finned Kassina tadpoles that lived in the middle of the water column. The translucent, slow swimming Phrynomantis microps tadpole occurred in larger ponds and preferred the upper water column in deeper parts of the pond. This species was especially at risk in ponds with reduced water levels. Turtles, in contrast to fish or dragonfly larvae, are capable of migrating to other ponds. They therefore might have a profound regional influence on tadpole communities in ephemeral savanna ponds.
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Mokany, Allie. "Impact of tadpoles and mosquito larvae on ephemeral pond structure and processes." Marine and Freshwater Research 58, no. 5 (2007): 436. http://dx.doi.org/10.1071/mf06201.
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Competition between organisms can influence both the abundance of species and the function of ecosystems. Here, I report the results of a field-based aquatic microcosm experiment, where the timing of arrival and abundance of two herbivores, tadpoles (Limnodynastes tasmaniensis) and mosquito larvae (Ochlerotatus notoscriptus), were manipulated to determine their impact on invertebrate community structure and ecosystem processes. Although successful establishment decreased with experimental time, there was no evidence that interactions between tadpoles and mosquitoes decreased the other species' subsequent survival. However, there were negative effects of tadpole addition on other invertebrates, with decreases in the abundance of zooplankton (Moina australiensis) and dipterans (Ephydridae and Chironomus oppositus). The addition of both tadpoles and mosquito larvae also increased ecosystem productivity. The negative effect of tadpoles on invertebrate abundance may result from competition for food or space, while complementary tadpole and mosquito effects on ecosystem processes are likely to result from changes in the dominant pond state. Tadpoles and mosquito larvae might influence the development of the dominant pond state through preferential consumption of edible phytoplankton and bacteria, reducing the competitive pressure on relatively inedible metaphyton, which forms dominating mats.
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Rossa-Feres, Denise de C., Jorge Jim, and Mariluce Gonçalves Fonseca. "Diets of tadpoles from a temporary pond in southeastern Brazil (Amphibia, Anura)." Revista Brasileira de Zoologia 21, no. 4 (December 2004): 745–54. http://dx.doi.org/10.1590/s0101-81752004000400003.
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The diet of tadpoles of 13 anuran species was determined to verify whether food resource partitioning occurs and whether the degree of diet similarity is related to taxonomic affinity. Tadpoles of all species studied were mainly herbivorous, except for these of Leptodactylus fuscus (Schneider, 1799) which were mycophagous. Although some species had exclusive items in their diet, most tadpole species ingested the same items, but differed in the amount of each item consumed. Two guilds were found: tadpoles that feed on diatoms on the pond bottom, and tadpoles that feed on Oedogonium Link, 1820 algae in midwater. Diet similarity was related to the taxonomic relationship, microhabitat and feeding behavior of tadpoles indicating that the community organization is complex and resulting from the interaction of several parameters.
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Faragher, Sarah Grimké, and Robert G. Jaeger. "Tadpole bullies: examining mechanisms of competition in a community of larval anurans." Canadian Journal of Zoology 76, no. 1 (January 1, 1998): 144–53. http://dx.doi.org/10.1139/z97-177.
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We examined interference competition during interspecific interactions of larval anurans to determine its importance. We conducted laboratory experiments to examine behavioral and chemical interference competition between tadpoles of the southern leopard frog (Rana utricularia) and those of the green treefrog (Hyla cinerea). Water preconditioned byR. utricularia tadpoles significantly decreased the growth and increased the mortality of H. cinerea tadpoles compared with control treatments. In addition, R. utricularia tadpoles inhibited the feeding rate ofH. cinerea tadpolesby harassing them, and these interactions significantly decreased the growth and increased the mortality of theH. cinerea tadpoles. Rana utricularia tadpoles apparently use both chemical interference and aggressive behavior in securing a competitive advantage over H. cinerea tadpoles, and the H. cinerea tadpoles suffer from these interactions. Intraspecific chemical and behavioral interference competition also significantly decreased the growth of larval H. cinerea. In natural ponds, R. utricularia tadpoles that inhibit the growth and increase the mortality of H. cinerea tadpoles may increase their own chances of survival and metamorphosis, while H. cinerea tadpoles that avoid interactions with conspecifics and with R. utricularia tadpoles may increase their own chances of survival and metamorphosis.
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Grayfer, Leon, Francisco De Jesús Andino, and Jacques Robert. "Prominent Amphibian (Xenopus laevis) Tadpole Type III Interferon Response to the Frog Virus 3 Ranavirus." Journal of Virology 89, no. 9 (February 25, 2015): 5072–82. http://dx.doi.org/10.1128/jvi.00051-15.
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ABSTRACTRanaviruses (Iridoviridae) are posing an increasing threat to amphibian populations, with anuran tadpoles being particularly susceptible to these viral infections. Moreover, amphibians are the most basal phylogenetic class of vertebrates known to possess both type I and type III interferon (IFN)-mediated immunity. Moreover, little is known regarding the respective roles of the IFN mediators in amphibian antiviral defenses. Accordingly, we transcriptionally and functionally compared the amphibianXenopus laevistype I (IFN) and III (IFN-λ) IFNs in the context of infections by the ranavirus frog virus 3 (FV3).X. laevisIFN and IFN-λ displayed distinct tissue expression profiles. In contrast to our previous findings thatX. laevistadpoles exhibit delayed and modest type I IFN responses to FV3 infections compared to the responses of adults, here we report that tadpoles mount timely and robust type III IFN gene responses. Recombinant forms of these cytokines (recombinantX. laevisIFN [rXlIFN] and rXlIFN-λ) elicited antiviral gene expression in the kidney-derived A6 cell line as well as in tadpole leukocytes and tissues. However, rXlIFN-λ was less effective than rXlIFN in preventing FV3 replication in A6 cells and tadpoles and inferior at promoting tadpole survival. Intriguingly, FV3 impaired A6 cell and tadpole kidney type III IFN receptor gene expression. Furthermore, in A6 cultures rXlIFN-λ conferred equal or greater protection than rXlIFN against recombinant viruses deficient for the putative immune evasion genes, the viral caspase activation and recruitment domain (vCARD) or a truncated vIF-2α gene. Thus, in contrast to previous assumptions, tadpoles possess intact antiviral defenses reliant on type III IFNs, which are overcome by FV3 pathogens.IMPORTANCEAnuran tadpoles, including those ofXenopus laevis, are particularly susceptible to infection by ranavirus such as FV3. We investigated the respective roles ofX. laevistype I and type III interferons (IFN and IFN-λ, respectively) during FV3 infections. Notably, tadpoles mounted timely and more robust IFN-λ gene expression responses to FV3 than adults, contrasting with the poorer tadpole type I IFN responses. However, a recombinantX. laevisIFN-λ (rXlIFN-λ) conferred less protection to tadpoles and the A6 cell line than rXlIFN, which may be explained by the FV3 impairment of IFN-λ receptor gene expression. The importance of IFN-λ in tadpole anti-FV3 defenses is underlined by the critical involvement of two putative immune evasion genes in FV3 resistance to IFN- and IFN-λ-mediated responses. These findings challenge the view that tadpoles have defective antiviral immunity and suggest, rather, that their antiviral responses are predominated by IFN-λ responses, which are overcome by FV3.
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Ngo, Binh Van, Ya-Fu Lee, and Chung D. Ngo. "Tadpole Survival and Metamorphosis in the Granular Spiny Frog, Quasipaa verrucospinosa (Dicroglossidae, Anura, Amphibia) in Central Vietnam." Russian Journal of Herpetology 27, no. 2 (April 25, 2020): 63–69. http://dx.doi.org/10.30906/1026-2296-2020-27-2-63-69.
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Little is known about many aspects of the tadpole ecology of Quasipaa verrucospinosa (Bourret, 1937), whereas this species has also been classified as Near Threatened (NT) due to habitat change and degradation, loss of forest and stream habitats and overexploitation. We conducted experiments in the field and collected tadpole data to estimate survival rates, growth rates, and age at metamorphosis. The average number of tadpoles per clutch was 518, the average survival ratio at the final stage of metamorphosis was 80%, and the total time to metamorphosis averaged 55.8 days. Multiple regression results for possible effects of water temperature, dissolved oxygen, and pH values on survival rates and the total time of tadpole metamorphosis were significant among localities. Water temperature and dissolved oxygen, but not pH values, were negatively associated with the survival ratio and metamorphosis time of tadpoles. At the beginning stage of metamorphosis (41 – 42), tadpoles had an average body weight of 2.7 g, a snout-vent length (SVL) of 24.8 mm, a tail length of 40.5 mm, and a total length of 65.3 mm. The process of metamorphosis is completed in stage 46, at which juvenile frogs had a mean body weight of 2.3 g and a mean SVL of 25.8 mm. We used a two-way multivariate analysis of variance to examine the effects of year and site factors on the variance in morphological measurements and body weightes of tadpoles. This analysis revealed that body sizes of tadpoles varied significantly among years, sites, and by site-year interaction. Water temperature and dissolved oxygen have major impacts on rates of growth, timing of metamorphosis, and body size of tadpoles at metamorphosis.
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Lawler, Karen L., and Jean-Marc Hero. "Palatability of Bufo marinus Tadpoles to a Predatory Fish Decreases with Development." Wildlife Research 24, no. 3 (1997): 327. http://dx.doi.org/10.1071/wr96089.
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This investigation showed an ontogenetic shift in the palatability of Bufo marinus tadpoles by measuring consumption of tadpoles at three different developmental stages (newly hatched, intermediate and pre- metamorphic) by an Australian predatory fish, Lates calcarifer (barramundi). A known-palatable tadpole, Limnodynastes ornatus, was used as the control. B. marinus tadpoles at all developmental stages were unpalatable relative to a palatable alternative, with the later stages being the least palatable. Choice experiments further demonstrated that L. calcarifer were able to recognise and choose L. ornatus tadpoles in preference to those of B. marinus. Our experiments demonstrate that at all stages of development, B. marinus tadpoles were unpalatable to L. calcarifer. Contrary to the model proposed by Brodie and Formanowicz (1987), our results suggest an ontogenetic shift in palatability of B. marinus tadpoles to a vertebrate fish predator, with the later stages being less palatable.
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VON MAY, RUDOLF, MARGARITA MEDINA–MÜLLER, MAUREEN A. DONNELLY, and Kyle Summers. "The tadpole of the bamboobreeding poison frog Ranitomeya biolat (Anura: Dendrobatidae)." Zootaxa 1857, no. 1 (August 27, 2008): 66. http://dx.doi.org/10.11646/zootaxa.1857.1.6.
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Ranitomeya biolat occurs in the lowland rainforest of southern Peru and northwestern Bolivia and uses bamboo internodes as a retreat and reproduction site (Morales 1992; Maldonado & Reichle 2007). Unlike other members of the vanzolinii group, which exhibit biparental care of tadpoles (Summers & McKeon 2004), we have observed that R. biolat exhibits male–only parental care and that tadpoles are transported individually and deposited in water–filled bamboo internodes (Medina–Müller 2006; R. von May, unpublished data). After more than 12 months of sampling, we never observed individuals providing trophic eggs to tadpoles or observed oophagy as clutches were laid 3.5 ± 1.5 cm above the water (n = 55); hence, tadpole oophagy may not be an important food resource as previously suspected (Waldram 2008). Though basic information on its breeding biology has been published (Waldram 2008), its tadpole remains undescribed. With the purpose of filling this gap, we here describe the tadpole of R. biolat.
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Gould, John. "Tadpoles of the sandpaper frog, Lechriodus fletcheri, hunt mosquito larvae in ephemeral pools." Australian Journal of Zoology 67, no. 1 (2019): 9. http://dx.doi.org/10.1071/zo19065.
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Amphibian tadpoles are generally considered to be herbivores or plant-based detritivores that occupy lower trophic levels within freshwater aquatic communities. However, tadpoles are known to incorporate a variety of animal products within their diets as well. There are also many examples of tadpole species occupying higher trophic levels as opportunistic predators of conspecifics and other animals. In this paper, I describe the opportunistic predation of mosquito larvae by tadpoles of the sandpaper frog, Lechriodus fletcheri. Field observations revealed that L. fletcheri tadpoles actively preyed on mosquito larvae at the surface of the water column, using a series of swimming-to-gliding motions to hunt. This swimming routine may be effective for catching mosquito larvae, which respond to water vibrations to evade predation, allowing tadpoles to effectively become ‘invisible’ to the larvae during periods when tail motions are ceased. Given that L. fletcheri tadpoles have a non-specialised omnivorous diet, these findings indicate that the tadpoles of some species have the ability to take up multiple ecological roles within freshwater systems, including as opportunistic predators.
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Haramura, Takashi. "Behavioural responses of cane toad (Rhinella marina) adults and tadpoles to chemical cues." Bangladesh Journal of Zoology 45, no. 2 (February 25, 2018): 149–57. http://dx.doi.org/10.3329/bjz.v45i2.35710.
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Pheromonal communication may be possible to control the invader animal. Pheromone-induced behavioural changes could be exploited to control invasive species such as the cane toad (Rhinella marina). Injured cane toad tadpoles are known to produce species-specific chemical cues that alert conspecific tadpoles to danger. These chemical cues reduce both the survival rate of other tadpoles and body size at metamorphosis, and suggest that cane toad tadpoles express chemical substances that control the behaviour of other tadpoles. Identification of the chemical substance(s) involving in tadpole could lead to the development of methods to control the behaviour of cane toad. Here, the behaviour of cane toad adults and tadpoles was characterized following exposure to chemical substances extracted from dead cane toad tadpoles using methanol (MeOH) or distilled water (H2O). Adult toads showed signs of avoiding water to which the H2O-extracted chemical cue had been added. By contrast, no differences were observed in the swimming behaviour of tadpoles (control, MeOHor H2O-extracted samples). These data indicate that development of a chemicalbased behaviour control method will require more detailed chemical analyses. We used dead tadpoles to extract chemical substrate, but in future studies, the potential behaviour-controlling chemical cues should be extracted from live cane toad tadpoles.Bangladesh J. Zool. 45(2): 149-157, 2017
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Heerema, J. L., S. J. Bogart, C. C. Helbing, and G. G. Pyle. "Olfactory epithelium ontogenesis and function in postembryonic North American Bullfrog (Rana (Lithobates) catesbeiana) tadpoles." Canadian Journal of Zoology 98, no. 6 (June 2020): 367–75. http://dx.doi.org/10.1139/cjz-2019-0213.
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During metamorphosis, the olfactory system remodelling in anuran tadpoles — to transition from detecting waterborne odorants to volatile odorants as frogs — is extensive. How the olfactory system transitions from the larval to frog form is poorly understood, particularly in species that become (semi-)terrestrial. We investigated the ontogeny and function of the olfactory epithelium of North American Bullfrog (Rana (Lithobates) catesbeiana Shaw, 1802) tadpoles at various stages of postembryonic development. Changes in sensory components observable at the epithelial surface were examined by scanning electron microscopy. Functionality of the developing epithelium was tested using a neurophysiological technique (electro-olfactography (EOG)), and behaviourally, using a choice maze to assess tadpole response to olfactory stimuli (algae extract, amino acids). The youngest (premetamorphic) tadpoles responded behaviourally to an amino acid mixture despite having underdeveloped olfactory structures (cilia, olfactory knobs) and no EOG response. The consistent appearance of olfactory structures in older (prometamorphic) tadpoles coincided with reliably obtaining EOG responses to olfactory stimuli. However, as tadpoles aged further, and despite indistinguishable differences in sensory components, behavioural- and EOG-based olfactory responses were drastically reduced, most strongly near metamorphic climax. This work demonstrates a more complex relationship between structure and function of the olfactory system during tadpole life history than originally thought.
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Hofmann, Sylvia, Rafaqat Masroor, and Daniel Jablonski. "Morphological and molecular data on tadpoles of the westernmost Himalayan spiny frog Allopaa hazarensis (Dubois & Khan, 1979)." ZooKeys 1049 (July 20, 2021): 67–77. http://dx.doi.org/10.3897/zookeys.1049.66645.
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Little is known about the life history, ecology, and distribution of the genus Allopaa (Dicroglossidae) and far less recent data are available about the larvae of this taxon. Here, we provide data on the larval stage of Allopaa hazarensis (Dubois & Khan, 1979) from northern Pakistan based on the examination of three tadpoles. Specimens were obtained from two sites in Buner, Khyber Pakhtunkhwa province, Pakistan. Morphological and genetic analysis (mtDNA and nDNA) confirmed the identity of the tadpoles as A. hazarensis. Tadpole characterizations were illustrated by detailed imagery. Basic measurements and details on oral apparatus provide relevant taxonomic characteristics to distinguish the tadpoles of this species from other spiny frogs. The illustration and description of the tadpole of A. hazarensis should facilitate the identification of this species in the field.
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Liu, H., R. Wassersug, and K. Kawachi. "A computational fluid dynamics study of tadpole swimming." Journal of Experimental Biology 199, no. 6 (June 1, 1996): 1245–60. http://dx.doi.org/10.1242/jeb.199.6.1245.
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The hydrodynamics and undulating propulsion of tadpoles were studied using a newly developed two-dimensional computational fluid dynamics (CFD) modeling method. The mechanism of thrust generation associated with the flow patterns during swimming is discussed. Our CFD analysis shows that the kinematics of tadpoles is specifically matched to their special shape and produces a jet-stream propulsion with high propulsive efficiency, as high as that achieved by teleost fishes. Investigation of the effect of Reynolds number indicates that the Froude efficiency increases with increasing Reynolds number with no ceiling in generating the jet-stream propulsion. Further studies using tadpole- and fish-shaped models with hindlimbs added to their body profiles reveal that the tadpole shape ­ a globose head with a tapered tail and hindlimbs at the base of the tail ­ allows tadpoles, but not fish, to develop hindlimbs with very little handicap on propulsion. The shapes and kinematics of tadpoles appear to be specially adapted to the requirement of these organisms to transform into frogs.
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WASSERSUG, RICHARD J., and KARIN VON SECHENDORF HOFF. "The Kinematics of Swimming in Anuran Larvae." Journal of Experimental Biology 119, no. 1 (November 1, 1985): 1–30. http://dx.doi.org/10.1242/jeb.119.1.1.
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The kinematics of swimming in tadpoles from four species of anurans (Rana catesbeiana Shaw, Rana septentrionalis Baird, Rana clamitans Latreille and Bufo americanus Holbrook) was studied using computer-assisted analysis of high speed (≥200 frames s−1) ciné records. 1. Tadpoles exhibit the same positive, linear relationship between tail beat frequency and specific swimming speed commonly reported for subcarangiform fishes. 2. Tadpoles show an increase in the maximum amplitude of the tail beat with increasing swimming speed up to approximately 4 lengths s−1. Above 4 lengths s−1, amplitude approaches an asymptote at approximately 25 % of length. 3. Tadpoles with relatively longer tails have lower specific amplitudes. 4. Froude efficiencies for tadpoles are similar to those reported for most subcarangiform fishes. 5. Bufo larvae tend to have higher specific maximum amplitude, higher tail beat frequencies, lower propeller efficiencies (at least at intermediate speeds) and substantially less axial musculature than do comparable-sized Rana larvae. These differences may relate to the fact that Bufo larvae are noxious to many potential predators and consequently need not rely solely on locomotion for defence. 6. Tadpoles exhibit larger amounts of lateral movement at the snout than do most adult fishes. 7. The point of least lateral movement during swimming in tadpoles is at the level of the semi-circular canals, as assumed in models on the evolution of the vertebrate inner ear. 8. Passive oscillation of anaesthetized and curarized tadpoles at the base of their tail produces normal kinematics in the rest of the tail. This supports the idea that muscular activity in the posterior, tapered portion of the tadpole tail does not serve a major role in thrust production during normal, straightforward swimming at constant velocity. 9. The angle of incidence and lateral velocity of the tail tip as it crosses the path of motion are not consistent with theoretical predictions of how thrust should be generated. The same parameters evaluated at the high point of the tail fin (approximately midtail) suggest that that portion of the tail generates thrust most effectively. 10. Ablation of the end of the tail in passively oscillated tadpoles confirms that the terminal portion of the tadpole tail serves to reduce excessive amplitude in the more anterior portion of the tail, where most thrust is generated. 11. The posterior portion of the tail is important in reducing turbulence around a tadpole. It may also function to produce thrust during irregular, intricate movements, such as swimming backwards. 12. Tadpoles are comparable to subcarangiform fishes of similar size in their maximum swimming speed and mechanical efficiency, despite the fact that they have much less axial musculature and lack the elaborate skeletal elements that stiffen the fins in fishes. The simple shape of the tadpole tail appears to allow these animals efficient locomotion over short distances and high manoeuvrability, while maintaining the potential for rapid morphological change at metamorphosis.
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Venesky, Matthew D., Shane M. Hanlon, Kyle Lynch, Matthew J. Parris, and Jason R. Rohr. "Optimal digestion theory does not predict the effect of pathogens on intestinal plasticity." Biology Letters 9, no. 2 (April 23, 2013): 20130038. http://dx.doi.org/10.1098/rsbl.2013.0038.
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One prediction of optimal digestion theory is that organisms will increase the relative length of their digestive tracts when food resources become limited. We used theory of optimal digestion to test whether tadpoles can adjust the relative length of their intestines when challenged with the fungal pathogen Batrachochytrium dendrobatidis ( Bd ). The degree of tadpole mouthpart damage, a symptom of Bd infections that reduces food consumption, was associated positively with the length of tadpole intestines relative to their body size, consistent with optimal digestion theory. After controlling for mouthpart damage, tadpoles exposed to Bd had shorter intestines relative to their body size, opposite to the predictions of optimal digestion theory. One explanation of why tadpoles with higher Bd loads have shorter relative intestinal lengths is that they divert energy from maintaining intestinal and overall growth towards anti-parasite defences.
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Schmidt, Katrin, Melanie L. Blanchette, Richard G. Pearson, Ross A. Alford, and Aaron M. Davis. "Trophic roles of tadpoles in tropical Australian streams." Freshwater Biology 62, no. 11 (October 15, 2017): 1929–41. http://dx.doi.org/10.1111/fwb.13036.
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Abstract Tadpoles can be abundant consumers in stream ecosystems, and may influence the structure and function of streams through their feeding activities and interactions with other organisms. To understand the contribution of tadpoles to stream functioning, and the potential impact of their loss, it is necessary to determine their diets and how they might influence food‐web structure. Using gut‐content analysis and stable‐isotope analysis of N and C, we determined the main food sources and trophic positions of tadpoles of five native frog species, invertebrates, and fish in upland and lowland Australian Wet Tropics streams. Omnivory was prevalent among the tadpoles and invertebrates. Tadpoles consumed different food according to availability and nutrient quality, but assimilated mainly biofilm and algae. Most tadpoles and invertebrates assimilated the same high‐quality foods. Food webs in upland riffles were simplified by local extinction of tadpoles, and were probably simplified in pools in the cooler months by seasonal decline in tadpole abundance. Food‐web complexity was increased in some pools by the presence of predatory fish and a greater number of basal sources. As tadpoles are important seasonal components in stream food webs, their local extinction can greatly alter food‐web structure and complexity and, possibly, processes such as leaf litter breakdown and sediment accumulation.
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Villatoro-Castañeda, Melissa, Zachery R. Forsburg, Whitney Ortiz, Sarah R. Fritts, Caitlin R. Gabor, and Camila Carlos-Shanley. "Exposure to Roundup and Antibiotics Alters Gut Microbial Communities, Growth, and Behavior in Rana berlandieri Tadpoles." Biology 12, no. 9 (August 25, 2023): 1171. http://dx.doi.org/10.3390/biology12091171.
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The gut microbiome is important for digestion, host fitness, and defense against pathogens, which provides a tool for host health assessment. Amphibians and their microbiomes are highly susceptible to pollutants including antibiotics. We explored the role of an unmanipulated gut microbiome on tadpole fitness and phenotype by comparing tadpoles of Rana berlandieri in a control group (1) with tadpoles exposed to: (2) Roundup® (glyphosate active ingredient), (3) antibiotic cocktail (enrofloxacin, sulfamethazine, trimethoprim, streptomycin, and penicillin), and (4) a combination of Roundup and antibiotics. Tadpoles in the antibiotic and combination treatments had the smallest dorsal body area and were the least active compared to control and Roundup-exposed tadpoles, which were less active than control tadpoles. The gut microbial community significantly changed across treatments at the alpha, beta, and core bacterial levels. However, we did not find significant differences between the antibiotic- and combination-exposed tadpoles, suggesting that antibiotic alone was enough to suppress growth, change behavior, and alter the gut microbiome composition. Here, we demonstrate that the gut microbial communities of tadpoles are sensitive to environmental pollutants, namely Roundup and antibiotics, which may have consequences for host phenotype and fitness via altered behavior and growth.