Skip to main content Skip to main navigation menu Skip to site footer
Type: Monograph
Published: 2007-09-28
Page range: 1–175
Abstract views: 477
PDF downloaded: 6

Anatomy of anuran tadpoles from lentic water bodies: systematic relevance and correlation with feeding habits

CONICET, Instituto de Herpetología, Fundación Miguel Lillo, Miguel Lillo 251, Tucumán, Argentina
Anura tadpoles chondrocranium hyobranchial skeleton musculature oral apparatus buccopharyngeal cavity gut content interspecific variation ecomorphology

Abstract

I studied anatomy, gut content, and the relationship among these traits in a set of anuran tadpoles. Larval stages (mainly Gosner stages 31–36) of nineteen species from various lentic environments were selected. Morphological characters from the skeleton, musculature, oral apparatus and buccopharyngeal cavity were recorded, and a gut content analysis was performed, with emphasis on food size distribution. Ordination techniques were applied in order to find patterns of similarity in morphology and gut content. Canonical ordination methods were used to investigate the relationship among gut content, morphology, and phylogeny in the species considered. The results show that several skeletal, muscular, and buccal characters are relatively maintained within genera. Other features, which have appeared independently in different lineages, reflect convergence phenomena in some cases related to ecological aspects. The configuration of the hyobranchial skeleton, the development of the buccal floor depressor and levator muscles, and mouth gape width correlate with prey size. In some species, morphology is clearly related with feeding. Tadpoles that ingest large food particles relative to their body length present morphological traits attributable to macrophagy. Taxonomically unrelated tadpoles of Dendropsophus nanus, D. microcephalus and Ceratophrys cranwelli possess hyobranchial skeletons with robust, rostrocaudally long ceratohyals and reduced branchial baskets with short ceratobranchials devoid of lateral projections and spicules. Lepidobatrachus llanensis tadpoles have laterally extended ceratohyals which, along with the lateral extension of the jaws, result in a very wide oral apparatus and an ample buccopharyngeal cavity that allows the tadpole to ingest large and whole prey; the branchial basket, although its ceratobranchials lack lateral projections and spicules, is slightly reduced in area. The four species mentioned have a noticeable development of the buccal floor depressor muscles, and buccal cavities with scarce filtering and entrapping structures. In Elachistocleis bicolor, Dermatonotus muelleri, Chiasmocleis panamensis, and Xenopus laevis tadpoles, the branchial basket occupies >70% of the total hyobranchial skeleton area, and the hypobranchial plates are highly reduced; the buccal floor levator muscles are well-developed, with an increased site of attachment on the ventral expansion of the lateral process of the ceratohyal; the scarcity of the filtering structures in the buccopharyngeal cavity are balanced with the great development of the branchial filters and secretory zones; all these features relate to a diet based on small particles not significantly different from those of most other species; however, experimental studies show that species with similar hyobranchial apparatus and muscles are the most efficient when retaining minute particles. Finally, a large group of species present generalized morphological characters, such as a branchial basket occupying about 50% of the total hyobranchial apparatus, intermediate values of mouth gape width and buccal floor levator / depressor muscles ratio, and abundant filtering structures in the buccopharyngeal cavity; these species feed frequently on food particles between 1–30% of the tadpole body length; however, in some of the species, macrophagous diets are also reported in the literature, indicating that this morphology is flexible in more ample prey size ranges.

References

  1. Abdala, V. & Moro, S.A. (1996) Cranial myology of South American Gekkonidae. Journal of Morphology, 229, 59–70.

    Adams, D.C. & Rohlf, F.J. (2000) Ecological character displacement in Plethodon: biomechanical differences found from a geometric morphometric study. Proceedings of the National Academy of Sciences, 97, 4106–4111.

    Adams, D.C., Rohlf, F.J. & Slice, D.E. (2004) Geometric morphometrics: ten years of progress following the ‘revolution’. Italian Journal of Zoology, 71, 5–16.

    Aguilar, C. & Pacheco, V. (2005) Contribución de la morfología bucofaríngea larval a la filogenia de Batrachophrynus y Telmatobius. Monografías de Herpetología, 7, 219–238.

    Alcalde, L. (2001) Descripción del condrocráneo prometamórfico de Hyla pulchella cordobae (Anura: Hylidae). In: IV Congreso Argentino de Herpetología. Salta, Argentina.

    Alcalde, L. (2005) Descripción de la musculatura craneana en larvas de anuros de las familias Hylidae y Leptodactylidae. Revista del Museo de La Plata, Zoología, 16, 1–12.

    Alcalde, L. & Barg, M. (2006) Chondrocranium and cranial muscle morphology in Lysapsus and Pseudis tadpoles (Anura: Hylidae: Hylinae). Acta Zoologica, 87, 91–100.

    Alcalde, L. & Rosset, S.D. (2003) Descripción y comparación del condrocráneo en larvas de Hyla raniceps (Cope, 1862), Scinax granulatus (Peters, 1871) y Scinax squalirostris (A. Lutz, 1925) (Anura: Hylidae). Cuadernos de Herpetología, 17, 33–49.

    Alcalde, L., Basso, N.G. & Lajmanovich, R.C. (2000) Morfología y desarrollo del esqueleto en Hyla pulchella pulchella Anura: Hylidae). In: XV Reunión de Comunicaciones Herpetológicas de la AHA. Bariloche, Argentina.

    Alcalde, L., Kolenc, F., Borteiro, C. & Baldo, D. (2006) Descripción del condrocráneo y de los músculos craneanos de las larvas de Scinax uruguayus y de dos especies del clado de Scinax catharinae (Anura: Hylidae). In: VII Congreso Argentino de Herpetología. Corrientes, Argentina.

    Alford, R.A. (1999) Ecology: resource use, competition, and predation. In: McDiarmid, R.W. & Altig, R. (Eds.), Tadpoles. The biology of anuran larvae. University of Chicago Press, Chicago and London, pp. 240–278.

    Altig, R. (2006) Discussions of the origin and evolution of the oral apparatus of anuran tadpoles. Acta Herpetologica, 2, 95–105.

    Altig, R. (2007) A primer for the morphology of anuran tadpoles. Herpetological Conservation and Biology, 2, 71–74.

    Altig, R. & Johnston, G.F. (1989) Guilds of anuran larvae: Relationships among developmental modes, morphologies and habits. Herpetological Monographs, 2, 81–109.

    Altig, R. & Kelly, J.P. (1974) Indices of feeding in anuran tadpoles as indicated by gut characteristics. Herpetologica, 30, 200–203.

    Altig, R. & McDiarmid, R.W. (1999a) Body Plan: Development and morphology. In: McDiarmid, R.W. & Altig, R. (Eds.), Tadpoles. The biology of anuran larvae. University of Chicago Press, Chicago and London, pp. 24–51.

    Altig, R. & McDiarmid, R.W. (1999b) Diversity. Familial and generic characterization. In: McDiarmid, R.W. & Altig, R. (Eds.), Tadpoles. The biology of anuran larvae. University of Chicago Press, Chicago and London, pp. 295–337.

    Altig, R., Whiles, M.R. & Taylor, C.L. (2007) What do tadpoles really eat? Assessing the trophic status of an understudied and imperiled group of consumers in freshwater habitats. Freshwater Biology, 52, 386–395.

    Anderson, L.C. & Roopnarine, P.D. (2005) Role of constraint and selection in the morphologic evolution of Caryocorbula (Mollusca: Corbulidae) from the Caribbean Neogene. Palaeontologia Electronica, 8, 1–18.

    Arias, M.M., Peltzer, P.M. & Lajmanovich, R.C. (2002) Diet of the giant tadpole Pseudis paradoxus platensis (Anura, Pseudidae) from Argentina. Phyllomedusa, 1, 97–100.

    Baylac, M., Villemant, C. & Simbolotti, G. (2003) Combining geometric morphometrics with pattern recognition for the investigation of species complexes. Biological Journal of the Linnean Society, 80, 89–98.

    Beszteri, B., Acs, E. & Medlin, L. (2005) Conventional and geometric morphometric studies of valve ultrastructural variation in two closely related Cyclotella species (Bacillariophyta). European Journal of Phycology, 40, 89–103.

    Blommers-Schlösser, R.M.A. (1975) Observations on the larval development of some Malagasy frogs, with notes on their ecology and biology (Anura; Dyscophynae, Scaphiophryninae and Cophylinae). Beaufortia, 24, 7–26.

    Bock, W.J. & Von Wahlert, G. (1965). Adaptation and the form-function complex. Evolution, 19, 269–299.

    Böck, J.W. & Shear, C.R. (1972) A staining method for gross dissection of vertebrate muscles. Anatomischer Anzeiger, 130, 222–227.

    Bokermann, W.C. (1967) Girinos de anfibios brasileiros, sobre um girino gigante de Pseudis paradoxus (Amphibia, Pseudidae). Revista Brasileira de Biologia, 27, 209–212.

    Bookstein, F.L. (1991) Morphometric tools for landmarks data, Cambridge University Press, Cambridge, United Kingdom.

    Borteiro, C., Kolenc, F. Tedros, M. & Prigioni, C. (2006) The tadpole of Chaunus dorbignyi (Duméril & Bibron) (Anura, Bufonidae). Zootaxa, 1308, 49–62.

    Cannatella, D. (1999) Architecture. Cranial and axial musculoskeleton. In: McDiarmid, R.W. & Altig, R. (Eds.), Tadpoles. The biology of anuran larvae. University of Chicago Press, Chicago and London, pp. 52–91.

    Caramaschi, U. & Niemeyer, H. (2003) Nova espécie do complexo de Bufo margaritifer (Laurenti, 1768) do estado do Mato Grosso do Sul, Brasil (Amphibia, Anura, Bufonidae). Boletim do Museo Nacional, 501, 1–16.

    Carr, K.M. & Altig, R. (1991) Oral disc muscles of anuran tadpoles. Journal of Morphology, 208, 271–277.

    Cei, J.M. (1980) Amphibians of Argentina. Monitore zoologico italiano, Monografía 2, XII+609.

    Claude, J., Pritchard, P., Tong, H., Paradis, E. & Auffray, J.C. (2004) Ecological correlates and evolutionary divergence in the skull of turtles: a geometric morphometric assessment. Systematic Biology, 53, 933–948.

    Corti, M., Di Giuliomaria, C. & Verheyen, W. (2000). Three-dimensional geometric morphometrics of the african genus Lophuromys (Rodentia, Muridae). Hystrix, 11, 145–154.

    Crump, M.L. (1983) Opportunistic cannibalism by amphibian larvae in temporary aquatic environments. American Naturalist, 121, 281–287.

    Chan, M.D. (2001) Fish ecomorphology: predicting habitat preferences of stream fishes from their body shape. Ph.D. Dissertation, Virginia Polytechnic Institute and State University, USA.

    Chaparro, J. C., Pramuk, J. B. & Gluesenkamp, A. G. (2007) A new species of arboreal Rhinella (Anura: Bufonidae) from cloud forest of Southeastern Perú. Herpetologica, 63, 203–212.

    Chou, W.H. & Lin, J.Y. (1997) Tadpoles of Taiwan. National Museum of Natural Science, Special Publication, 7, 1–98.

    Clifton, K.B. & Motta, P.J. (1998) Feeding morphology, diet, and ecomorphological relationships among five Caribbean labrids (Teleostei, Labridae). Copeia, 1998, 953–966.

    Dayton, G.H, Saenz, D., Baum, K.A., Langerhans, B. & DeWitt, T.J. (2005) Body shape, burst speed and escape behavior of larval anurans. Oikos, 111, 582–591.

    Deban, S.M. & Olson, W.M. (2002) Suction feeding by a tiny predatory tadpole. Nature, 420, 41–42.

    Deban, S.M., O’Reilly, J.O. & Nishikawa, K.C. (2001) The evolution of the motor control of feeding in amphibians. American Zoologist, 41, 1280–1298.

    De Sá, R.O. (1988) Chondrocranium and ossification sequence of Hyla lanciformis. Journal of Morphology, 195, 345–355.

    De Sá, R.O. & Lavilla, E.O. (1997) The tadpole of Pseudis minutus (Anura: Pseudidae), an apparent case of heterochrony. Amphibia-Reptilia, 18, 229–240.

    De Sá, R.O. & Trueb, L. (1991) Osteology, skeletal development, and chondrocranial structure of Hamptophryne boliviana (Anura: Microhylidae). Journal of Morphology, 209, 311–330.

    D’Heursel, A. & De Sá, R.O. (1999) Comparing the tadpoles of Hyla geographica and Hyla semilineata. Journal of Herpetology, 33, 353–361.

    Diaz-Paniagua, C. (1985) Larval diets related to morphological characters of five anuran species in the Biological Reserve of Doñana (Huelva, Spain). Amphibia-Reptilia, 6, 307–321.

    Diaz-Paniagua, C. (1989) Larval diets of two anuran species, Pelodytes punctatus and Bufo bufo, in SW Spain. Amphibia-Reptilia, 10, 71–75.

    Dickie, L.M., Kerr, S.R. & Boudreau, P.R. (1987) Size-dependent processes underlying regularities in ecosystem structure. Ecological Monographs, 57, 233–250.

    Donnelly, M.A., De Sá, R.O. & Guyer, C. (1990) Description of the tadpoles of Gastrophryne pictiventris and Nelsonophryne aterrima (Anura: Microhylidae), with a review of morphological variation in free-swimming microhylid larvae. American Museum Novitates, 2976, 1–19.

    Duellman, W.E. (1970) The hylid frogs of Middle America. Monographs of the Museum of Natural History, University of Kansas, 1, 1–173.

    Duellman, W.E. (1978) The biology of an equatorial herpetofauna in Amazonian Ecuador. Miscellaneous Publication of the Museum of Natural History, University of Kansas, 65, 1–352.

    Duellman, W.E. & Fouquette, M.J. (1968) Middle American frogs of the Dendropsophus microcephalus group. Publications of the Museum of Natural History, University of Kansas, 17, 517–557.

    Duellman, W.E. & Trueb, L. (1986) Biology of Amphibians, McGraw-Hill, New York, USA.

    Duellman, W.E. & Wiens, J.J. (1993) Hylid frogs of the genus Scinax Wagler, 1830, in Amazonian Ecuador and Peru. Occasional Papers of the Museum of Natural History, University of Kansas, 153, 1–57.

    Dutra, S.L. & Callisto, M. (2005) Macroinvertebrates as tadpole food: importance and body size relationships. Revista Brasileira de Zoologia, 22, 923–927.

    Echeverría, D.D. (1992) Microscopía electrónica de barrido del aparato bucal de la larva de Hyla pulchella pulchella (Anura: Hylidae). Cuadernos de Herpetología, 7, 24–29.

    Echeverría, D.D. (1997a) Microscopía electrónica de barrido del aparato bucal y de la cavidad oral de la larva de Hyla strigilata eringiophila Gallardo, 1961 (Anura, Hylidae) con comentarios que facilitan su identificación durante la metamorfosis y postmetamorfosis. Physis, 54B, 1–6.

    Echeverría, D.D. (1997b) Microanatomy of the oral apparatus and oral cavity of Hyla minutus Peters, 1872 larvae (Anura, Hylidae), with data on feeding habits. Alytes, 15, 26–36.

    Echeverría, D.D. (1998) Microanatomía del aparato bucal y de la cavidad oral de la larva de Bufo fernandezae Gallardo, 1957 (Anura, Bufonidae), con comentarios acerca de la coloración in vivo y la anatomía externa. Alytes, 16, 50–60.

    Echeverría, D.D. & Lavilla, E.O. (2000) Internal oral morphology of tadpoles of Dermatonotus muelleri and Elachistocleis bicolor. Journal of Herpetology, 34, 517–523.

    Echeverría, D.D. & Montanelli, S.C. (1992) Estereomorfología del aparato bucal y de la cavidad oral de las larvas de Ololygon fuscovaria (Lutz, 1925) (Anura, Hylidae). Revista del Museo Argentino de Ciencias Naturales, Zoología, 16, 3–13.

    Emerson, S.C. (1985) Skull shape in frogs – Correlations with diet. Herpetologica, 41, 177–187.

    Fabrezi, M. (1988) Metamorfosis en Pleurodema borellii (Anura: Leptodactylidae). Estudio del neurocráneo, esqueleto visceral y musculatura asociada. Master Dissertation, Universidad Nacional de Tucumán, Argentina.

    Fabrezi, M. (2004) Variación ontogenética y estructural en Ceratophryinae. In: V Congreso Argentino de Herpetología. San Juan, Argentina.

    Fabrezi, M. (2006) Morphological evolution of Ceratophryinae (Anura, Neobatrachia). Journal of Zoological Systematics & Evolutionary Research, 44, 153–166.

    Fabrezi, M. & García, G. (1994) Metamorfosis del aparato hiobranquial en Pleurodema borelli y Ceratophrys cranwelli (Anura: Leptodactylidae). Acta Zoológica Lilloana, 42, 189–192.

    Fabrezi, M. & Lavilla, E.O. (1992) Estructura del condrocráneo y esqueleto hiobranquial en larvas de algunos hílidos neotropicales (Anura: Hylidae). Acta Zoológica Lilloana, 41, 155–164.

    Fabrezi, M. & Lavilla, E.O. (1993) Anatomía del condrocráneo en larvas de tres especies de Telmatobius del grupo meridional (Anura: Leptodactylidae). Physis, 48B, 39–46.

    Fabrezi, M. & Vera, R. (1997) Caracterización morfológica de larvas de anuros del noroeste argentino. Cuadernos de Herpetología, 11, 37–49.

    Faivovich, J. (2002) A cladistic analysis of Scinax (Anura: Hylidae). Cladistics, 18, 367–393.

    Faivovich, J., Haddad, C.F.B., Garcia, P.C.A, Frost, D.R., Campbell, J.A. & Wheeler, W.C. (2005) Systematic review of the frog family Hylidae, with special reference to Hylinae: phylogenetic analysis and taxonomic revision. Bulletin of the American Museum of Natural History, 294, 1–240.

    Ferry-Graham, L.A., Bolnick, D.I. & Wainwright, P.C. (2002) Using functional morphology to examine the ecology and evolution of specialization. Integrative and Comparative Biology, 42, 265–277.

    Fink, W.L. & Zelditch, M.L. (1995) Phylogenetic analysis of ontogenetic shape transformations: a reassessment of the piranha genus Pygocentrus (Teleostei). Systematic Biology, 44, 343–360.

    Fiorito de López, L.E. & Echeverría, D.D. (1984) Morfogénesis de los dientes larvales y pico córneo de Bufo arenarum (Anura: Bufonidae). Revista del Museo Argentino de Ciencias Naturales, Zoología, 13, 573–578.

    Fiorito de López, L.E. & Echeverría, D.D. (1989) Microanatomía e histogénesis del aparato bucal en las larvas de Bufo arenarum (Anura: Bufonidae). Cuadernos de Herpetología, 4, 4–10.

    Frieß, M. (2003) An application of the relative warps analysis to problems in human paleontology - with notes on raw data quality. Image Analysis & Stereology, 22, 63–72.

    Frost, D.R. (2007) Amphibian Species of the World: an Online Reference Version 5.0 (1 February, 2007), American Museum of Natural History, New York, USA. Available from: http://research.amnh.org/herpetology/amphibia/index.php (accessed June 2007).

    Frost, D.R., Grant, T., Faivovich, J., Bain, R.H., Haas, A., Haddad, C.F.B., De Sá, R., Channing, A., Wilkinson, M., Donnellan, S.C., Raxworthy, C.J., Campbell, J.A., Blotto, B.L., Moler, P., Drewes, R.C., Nussbaum, R.A., Lynch, J.D., Green, D.M. & Wheeler, W.C. (2006) The amphibian tree of life. Bulletin of the American Museum of Natural History, 297, 1–370.

    Gans, C. & De Vee, F. (1987) Functional bases of fiber length and angulation in muscle. Journal of Morphology, 192, 63–85.

    Gans, C., De Vee, F. & Carrier, C. (1985) Usage pattern of the complex masticatory muscles in the shingle-back lizard, Trachydosaurus rugosus: A model for muscle placement. American Journal of Anatomy, 173, 219–240.

    Giannini, N.P. (1999) Las interacciones de aves-murciélagos-plantas en el sistema de frugivoría y dispersión de semillas en San Javier, Tucumán, Argentina. Ph.D. Dissertation, Universidad Nacional de Tucumán, Argentina.

    Giannini, N.P. (2003) Canonical Phylogenetic Ordination. Systematic Biology, 52, 684–695.

    Giri, F. & Collins, P.A. (2004) A geometric morphometric analysis of two sympatric species of the family Aeglidae (Crustacea, Decapoda, Anomura) from La Plata basin. Italian Journal of Zoology, 71, 85–88.

    Glos, J., Glaw, F. & Vences, M. (2005) A new species of Scaphiophryne from Western Madagascar. Copeia, 2005, 252–261.

    Gosner, K.L. (1960) A simplified table for staging anuran embryos and larvae with notes on identification. Herpetologica, 16, 183–190.

    Gradwell, N. (1971) Xenopus tadpole: on the water pumping mechanism. Herpetologica, 27, 107–123.

    Gradwell, N. (1972) Gill irrigation in Rana catesbeiana. II. On the musculoskeletal mechanism. Canadian Journal of Zoology, 50, 501–521.

    Gradwell, N. (1974) Description of the tadpole of Phrynomerus annectens, and comments on its gill irrigation mechanism. Herpetologica, 30, 53–62.

    Grosjean, S. (2001) The tadpole of Leptobrachium (Vibrissaphora) echinatum (Amphibia, Anura, Megophryidae). Zoosystema, 23, 143–156.

    Grosjean, S., Vences, M. & Dubois, A. (2004) Evolutionary significance of oral morphology in the carnivorous tadpoles of tiger frogs, genus Hoplobatrachus (Ranidae). Biological Journal of the Linnean Society, 81, 171–181.

    Haas, A. (1995) Cranial features of dendrobatid larvae (Amphibia: Anura: Dendrobatidae). Journal of Morphology, 224, 241–264.

    Haas, A. (1996a) Das larvale Cranium von Gastrotheca riobambae und seine Metamorphose (Amphibia, Anura, Hylidae). Verhandlungen des naturwissenschaftlichen Vereins, Hamburg, 36, 33–162.

    Haas, A. (1996b) Non-feeding and feeding tadpoles in hemiphractine frogs: larval head morphology, heterochrony, and systematics of Flectonotus goeldii (Amphibia: Anura: Hylidae). Journal of Zoological Systematics & Evolutionary Research, 34, 163–171.

    Haas, A. (2001) Mandibular arches musculature of anuran tadpoles, with comments on homologies of amphibian jaw muscles. Journal of Morphology 247, 1–33.

    Haas, A. (2003) Phylogeny of frogs as inferred from primarily larval characters (Amphibia: Anura). Cladistics, 19, 23–89.

    Haas, A. & Richards, S.J. (1998) Correlations of cranial morphology, ecology and evolution in australian suctorial tadpoles of the genera Litoria and Nyctimystes (Amphibia: Anura: Hylidae: Pelodryadinae). Journal of Morphology, 238, 109–141.

    Haas, A., Hertwig, S. & Das, I. (2006) Extreme tadpoles: the morphology of the fossorial megophryid larva, Leptobrachella mjobergi. Zoology, 109, 26–42.

    Hall, J.A. & Larsen, J.H. Jr. (1998) Postembryonic ontogeny of the Spadefoot toad, Scaphiopus intermontanus (Anura: Pelobatidae): skeletal morphology. Journal of Morphology, 238, 179–244.

    Hall, J.A., Larsen, J.H. Jr. & Fitzner, R.E. (2002) Morphology of the prometamorphic larva of the Spadefoot toad, Scaphiopus intermontanus (Anura: Pelobatidae), with an emphasis on the lateral line system and mouthparts. Journal of Morphology, 252, 114–130.

    Harmon, L.J., Kolbe, J.J., Cheverud, J.M. & Losos, J.C. (2005) Convergence and the multidimensional niche. Evolution, 59, 409–421.

    Harvey, P.H. & Pagel, M.D. (1991) The comparative method in evolutionary biology, Oxford Series in Ecology and Evolution Volume 1, Oxford University Press, Oxford, United Kingdom.

    Hero, J.M. & Mijares-Urrutia, A. (1995) The tadpole of Scinax rostrata (Anura: Hylidae). Journal of Herpetology, 29, 307–309.

    Hespenheide, H.A. (1973) Ecological inferences from morphological data. Annual Review of Ecology and Systematics, 4, 213–229.

    Heyer, W.R. (1973) Ecological interactions of frog larvae at a seasonal tropical location in Thailand. Journal of Herpetology, 7, 337–361.

    Heyer, W.R. (1976) Studies in larval amphibian habitat partitioning. Smithsonian Contributions to Zoology, Washington, 242, 1–27.

    Hoff, K.S., Blaustein, A.R., McDiarmid, R.W. & Altig, R. (1999) Behavior: interactions and their consequences. In: McDiarmid, R.W. & Altig, R. (Eds.), Tadpoles. The biology of anuran larvae. University of Chicago Press, Chicago and London, pp. 215–239.

    Horiuchi, S. & Koshida, Y. (1989) Effects of foodstuffs on intestinal length in larvae of Rhacophorus arboreus (Anura: Rhacophoridae). Zoological Science, 6, 321–328.

    Hunte-Brown, M.E. (2006) The effects of extirpation of frogs on the trophic structure in tropical montane streams in Panama. Ph.D. Dissertation, Drexel University, USA.

    Huysentruyt, F., Adriaens, D., Teugels, G.G., Devaere, S., Herrel, A., Verraes, W. & Aerts, P. (2004) Diet composition in relation to morphology in some African anguilliform clariid catfishes. Belgian Journal of Zoology, 134, 25–30.

    Hyslop, E.J. (1980) Stomach content analysis–a review of methods and their application. Journal of Fish Biology, 17, 411–429.

    Inger, R.F. (1985) Tadpoles of the forested regions of Borneo. Fieldiana Zoology, 26, 1–89.

    Inger, R.F. (1986) Diets of tadpoles living in a Bornean rain forest. Alytes, 5, 153–164.

    Inthara, D., Lauhachinda, V., Nabhitabhata, J., Chuaynkern, Y. & Kumtong, P. (2005) Mouth part structures and distribution of some tadpoles from Thailand. The Thailand Natural History Museum Journal, 1, 55–78.

    Jongman, R.H.G., Ter Braak, C.J.F. & Van Tongeren, O.F.R. (1995) Data analysis in community and landscape ecology, Cambridge University Press, Cambridge, United Kingdom.

    Jungfer, K.H. (1996) Reproduction and parental care of the Coronated treefrog Anotheca coronata (Steindachner 1864) (Anura: Hylidae). Herpetologica, 52, 25–32.

    Khan, M.S. (1997) The oropharyngeal morphology and feeding habits of tadpole of tiger frog Rana tigerina Daudin. Russian Journal of Herpetology, 2, 163–171.

    Khan, M.S. (2003) The larval hyobranchial skeleton of five anuran species and its ecological correlates (Amphibia: Anura). Herpetozoa, 16, 133–140.

    Kehr, A.I. & Basso, N.G. (1990) Description of the tadpole of Lysapsus limellus (Anura: Pseudidae) and some considerations on its biology. Copeia, 1990, 573–575.

    Kenny, J.S. (1969) Feeding mechanisms in anuran larvae. Journal of Zoology, 157, 225–246.

    Koehl, M.A.R. (1996) When does morphology matter? Annual Review of Ecology and Systematics, 27, 501–42.

    Kolenc, F., Borteiro, C., Tedros, M., Núñez, D. & Maneyro, R. (2006) The tadpole of Physalaemus henselii (Peters) (Anura: Leiuperidae). Zootaxa, 1360, 41–50.

    Kolenc, F., Borteiro, C., Tedros, M. & Prigioni, C. (2007) The tadpole of Scinax aromothyella (Anura: Hylidae) from Uruguay. Studies on Neotropical Fauna and Environment, 42, 00–00.

    Kupferberg, S.J. (1997) The role of larval diet in anuran metamorphosis. American Zoologist, 37, 146–159.

    Lajmanovich, R.C. (1994) Contribución al conocimiento de la alimentación de larvas de la rana criolla Leptodactylus ocellatus (Amphibia, Leptodactylidae) en el Paraná medio, Argentina. Studies on Neotropical Fauna and Environment, 29, 55–61.

    Lajmanovich, R.C. (1997) Alimentación de larvas de anuros en ambientes temporales del sistema del Río Paraná, Argentina. Doñana Acta Vertebrata, 24, 191–202.

    Lajmanovich, R.C. (1998) Estructura de una comunidad larval de anuros vinculada al ecosistema del Río Paraná medio. Ph.D. Dissertation, Universidad Nacional de La Plata, Argentina.

    Lajmanovich, R.C. & Fernández, V. (1995) Alimentación de larvas de Bufo arenarum Hensel 1867 (Amphibia: Bufonidae) en ambientes del Río Paraná. Boletín del Museo Nacional de Historia Natural de Chile, 45, 7–18.

    Lanoo, M.J., Townsend, D.S. & Wassersug, R.J. (1987) Larval life in the leaves: arboreal tadpoles types, with special attention to the morphology, ecology, and behavior of the oophagous Osteopilus brunneus (Hylidae) larva. Fieldiana Zoology, 38, 1–31.

    Larson, A. & Losos, J.C. (1996) Phylogenetics systematics of adaptation. In: Rose, M.R. & Lauder, G.V. (Eds.), Adaptation. Academic Press, San Diego, USA, pp. 137–220.

    Larson, P.M. (2002) Chondrocranial development in larval Rana sylvatica (Anura: Ranidae): morphometric analysis of cranial allometry and ontogenetic shape change. Journal of Morphology, 252, 131–144.

    Larson, P.M. (2005) Ontogeny, phylogeny, and morphology in anuran larvae: morphometric analysis of cranial development and evolution in Rana tadpoles (Anura: Ranidae). Journal of Morphology, 264, 34–52.

    Larson, P.M. & De Sá, R.O. (1998) Chondrocranial morphology of Leptodactylus larvae (Leptodactylidae: Leptodactylinae): its utility in phylogenetic reconstruction. Journal of Morphology, 238, 287–306.

    Larson, P.M. & Reilly, S.M. (2003) Functional morphology of feeding and gill irrigation in the anuran tadpole: electromyography and muscle function in larval Rana catesbeiana. Journal of Morphology, 255, 202–214.

    Larson, P.M., De Sá, R.O. & Arrieta, D. (2003) Chondrocranial, hyobranchial and internal oral morphology in larvae of the basal Bufonid genus Melanophryniscus (Amphibia: Anura). Acta Zoologica, 84, 145–154.

    Lauder, G.V. (1996) The argument from design. In: Rose, M.R. & Lauder, G.V. (Eds.), Adaptation. Academic Press, San Diego, USA, pp. 55–91.

    Lavilla, E.O. (1983a) Consideraciones sobre el régimen ileófago en larvas de Hyla pulchella andina de la Sierra de Metán. Boletín de la Asociación Herpetológica Argentina, 1, 1–3.

    Lavilla, E.O. (1983b) Sistemática de larvas de Telmatobiinae (Anura: Leptodactylidae). Ph.D. Dissertation, Universidad Nacional de Tucumán, Argentina.

    Lavilla, E.O. (1987) La larva de Rhinoderma darwinii D. y C. (Anura: Rhinodermatidae). Acta Zoológica Lilloana, 39, 81–88.

    Lavilla, E.O. (1990) The tadpole of Hyla nana (Anura: Hylidae). Journal of Herpetology, 24, 207–209.

    Lavilla, E.O. (1991) Condrocráneo y esqueleto visceral en larvas de Cycloramphus stejnegeri (Leptodactylidae). Amphibia-Reptilia, 12, 33–38.

    Lavilla, E.O. (1992a) Estructura del condrocráneo y esqueleto visceral de larvas de Alsodes barrioi (Anura: Leptodactylidae). Acta Zoológica Lilloana, 42, 13–17.

    Lavilla, E.O. (1992b) The tadpole of Dermatonotus muelleri (Anura: Microhylidae). Bolletino Museo Regionale Scienze Naturali Torino, 10, 63–71.

    Lavilla, E.O. & De la Riva, I. (1993) La larva de Telmatobius bolivianus (Anura, Leptodactylidae). Alytes, 11, 37–46.

    Lavilla, E.O. & De Sá, R.O. (1999) Estructura del condrocráneo y esqueleto visceral de larvas de Pseudis minutus (Anura: Pseudidae). Alytes, 16, 139–147.

    Lavilla, E.O. & De Sá, R.O. (2001) Chondrocranium and visceral skeleton of Atelopus tricolor and Atelophryniscus chrysophorus tadpoles (Anura, Bufonidae). Amphibia-Reptilia, 22, 167–177.

    Lavilla, E.O. & Fabrezi, M. (1987) Anatomía de larvas de Hyla pulchella andina (Anura: Hylidae). Physis, 45, 77–82.

    Lavilla, E.O. & Fabrezi, M. (1992) Anatomía craneal de larvas de Lepidobatrachus llanensis y Ceratophrys cranwelli (Anura: Leptodactylidae). Acta Zoológica Lilloana, 42, 5–11.

    Lavilla, E.O. & Langone, J. (1995) Estructura del condrocráneo y esqueleto visceral de larvas de Elachistocleis bicolor (Valenciennes, 1838) (Anura: Microhylidae). Cuadernos de Herpetología, 9, 45–49.

    Lavilla, E.O. & Vaira, M. (1997) Larval chondrocranium of Gastrotheca christiani (Hylidae), with comments on the chondrocrania of non-feeding larvae in Anura. In: Third World Congress of Herpetology. Prague, Czech Republic.

    Leisler, B. & Winkler, H. (1985) Ecomorphology. In: Johnston, R.F. (Ed.), Current Ornithology Volume 2. Plenum Press, New York, USA, pp. 155–186.

    MacArthur, R.H. & Pianka, E.R. (1966) On optimal use of a patchy environment. American Naturalist, 100, 603–609.

    Maglia, A.M., Púgener, L.A. & Trueb, L. (2001) Comparative development of anurans: using phylogeny to understand ontogeny. American Zoologist, 41, 538–551.

    Marcus, L.F., Hingst-Zaher, E. & Zaher, H. (2000) Application of landmark morphometrics to skulls representing the orders of living mammals. Hystrix, 11, 27–47.

    Margalef, R. (1980) La biosfera: entre la termodinámica y el juego. Editorial Omega, Barcelona, España.

    McDiarmid, R.W. & Altig, R. (1990) Description of a Bufonid and two hylid tadpoles from western Ecuador. Alytes, 8, 51–60.

    McDiarmid, R.W. & Altig, R. (1999) Research. Materials and techniques. In: McDiarmid, R.W. & Altig, R. (Eds.), Tadpoles. The biology of anuran larvae. University of Chicago Press, Chicago and London, pp. 7–23.

    McGarigal, K., Cushman, S. & Stafford, S. (2000) Multivariate Statistics for wildlife and ecology research, Springer.

    Monteiro, L.R. & Abe, A.S. (1997) Allometry and morphological integration in the skull of Tupinambis merianae (Lacertilia: Teiidae). Amphibia-Reptilia, 18, 397–405.

    Monteiro, L.R. & Abe, A.S. (1999) Functional and historical determinants of shape in the scapula of xenarthran mammals: evolution of a complex morphological structure. Journal of Morphology, 241, 251–263.

    Monteiro, L.R. & Furtado dos Reis, S. (1999) Princípios de morfometria geométrica, Holos Editora Ltda-Me, Brasil.

    Monteiro, L.R., Lessa, L.G. & Abe, A.S. (1999) Ontogenetic variation in skull shape of Trichomys apereoides (Rodentia: Echimydae). Journal of Mammalogy, 80, 102–111.

    Motta, P.J., Norton, S.F. & Luczkovich, J.J. (1995a) Perspectives on the ecomorphology of bony fishes. Environmental Biology of Fishes, 44, 11–20.

    Motta, P.J., Clifton, K.B., Hernandez, P. & Eggold, B.T. (1995b) Ecomorphological correlates in ten species of subtropical seagrass fishes: diet and microhabitat utilization. Environmental Biology of Fishes, 44, 37–60.

    Nascimento, L.B., Caramaschi, U. and Cruz. C.A.G. (2005) Taxonomic review of the species groups of the genus Physalaemus fitzinger, 1826 with revalidation of the genera Engystomops Jiménez de la Espada, 1872 and Eupemphix Steindachner, 1863 (Amphibia, Anura, Leptodactylidae). Arquivos do Museu Nacional Rio de Janeiro, 63, 297–320.

    Nathan, J.M. & James, E.G. (1972) The role of protozoa in the nutrition of tadpoles. Copeia, 1972, 669–679.

    Noble, G.K. (1929) The adaptive modifications of the arboreal tadpoles of Hoplophryne and the torrent tadpoles of Staurois. Bulletin of the American Museum of Natural History, 58, 291–337.

    Orton, G.L. (1943) The tadpole of Rhinophrynus dorsalis. Occasional Papers of the Museum of Zoology, University of Michigan, 472, 1–7.

    Orton, G.L. (1953) The systematics of vertebrate larvae. Systematic Zoology, 2, 63–75.

    Palavecino, P. (1997) La musculatura mandibular e hioidea de Leptodactylus chaquensis (Anura: Leptodactylidae). Cuadernos de Herpetología, 11, 1–6.

    Palavecino, P. (1999) Musculatura asociada al primer y segundo arco visceral de algunos anuros leptodactílidos. Cuadernos de Herpetología, 13, 37–46.

    Palavecino, P. (2000) Desarrollo de la musculatura mandibular e hioidea en Leptodactylinae del noroeste argentino. Ph.D. Dissertation, Universidad Nacional de Tucumán, Argentina.

    Perotti, G. & Céspedez, J.A. (1999) The tadpole of Physalaemus santafecinus, with comments on buccopharyngeal morphology. Journal of Herpetology, 33, 312–315.

    Petranka, J.W. & Kennedy, C.A. (1999) Pond tadpoles with generalized morphology: is it time to reconsider their functional roles in aquatic communities? Oecologia, 120, 621–631.

    Pfennig, D.W. & Murphy, P.J. (2000) Character displacement in polyphenic tadpoles. Evolution, 54, 1738–1749.

    Pfennig, D.W. & Murphy, P.J. (2002) How fluctuating competition and phenotypic plasticity mediate species divergence. Evolution, 56, 1217–1228.

    Pomeroy, L.V. (1981) Developmental polymorphism in the tadpoles of the Spadefoot toad, Scaphiopus multiplicata. Ph.D. Dissertation, University of California, USA.

    Pramuk, J.B. (2006) Phylogeny of South American Bufo (Anura: Bufonidae) inferred from combined evidence. Zoological Journal of the Linnean Society, 146, 407–452.

    Púgener, L.A., Maglia, A.M. & Trueb, L. (2003) Revisiting the contribution of larval characters to an analysis of phylogenetic relationships of basal anurans. Zoological Journal of the Linnean Society, 139, 129–155.

    Quammen, J.K. & Durtsche, R.D. (2003) Diet comparison in three tadpole species, Rana sylvatica, Bufo americanus, Pseudacris crucifer, in a northern temperate climate. Norse Scientist, 1, 45–50.

    Rada, D. & Bello, R. (1988) Morfología e histología del sistema digestivo de la larva de Pseudis paradoxus caribensis Gallardo, 1961 (Amphibia, Pseudidae). Iheringia Serie Miscelanea, 2, 89–91.

    Ramaswami, L.S. (1940) Some aspects of the chondrocranium of the South Indian frogs. Journal of Mysore University, 1, 15–41.

    Ramaswami, L.S. (1941) Some aspects of the head of Xenopus laevis. Proceedings of the Indian Science Congress, 28, 183–184.

    Relyea, R.A. & Auld, J.R. (2004) Having the guts to compete: how intestinal plasticity explains costs of inducible defences. Ecological Letters, 7, 869–875.

    Ridewood, W.G. (1897) On the structure and development of the hyobranchial skeleton and larynx in Xenopus and Pipa; with remarks on the affinities of the Aglossa. Journal of the Linnean Society, 26, 53–128.

    Ridewood, W.G. (1898) On the larval hyobranchial skeleton of the anurous batrachians, with special reference to the axial parts. Journal of the Linnaean Society, 26, 474–487.

    Rodríguez, J. (2005) La estructura de tamaños del plancton: un tópico interdisciplinar y Margalefiano. Ecosistemas, 1, 1-11.

    Rohlf, F.J. (1993) Relative warp analysis and an example of its application to mosquito wings. In: Marcus, L.F., Bello, E. & García Valdecasas, A. (Eds.), Contributions to morphometrics Volume 8. Museo Nacional de Ciencias Naturales, Madrid, España, pp. 131–159.

    Rohlf, F.J. (2003) tpsRelw, Version 1.37 Copyright © 2003, New York: Ecology & Evolution, SUNY at Stony Brook. Available from: http://life.bio.sunysb.edu/morph/soft-tps.html (accessed September 2006).

    Rohlf, F.J. (2004) tpsSplin Version 1.19 Copyright © 2004, New York: Ecology & Evolution, SUNY at Stony Brook. Available from: http://life.bio.sunysb.edu/morph/soft-tps.html (accessed September 2006).

    Rohlf, F.J. (2005) tpsDIG2 Version 2.04 Copyright © 2005, New York: Ecology & Evolution, SUNY at Stony Brook. Available from http://life.bio.sunysb.edu/morph/soft-dataacq.html (accessed September 2006).

    Rohlf, F.J. & Bookstein, F.L. (1990) Proceedings of the Michigan Morphometrics Workshop, Special Publication 2, University of Michigan, USA.

    Rossa-Feres, D.C., Jim, J. & Gonçalves Fonseca, M. (2004) Diets of tadpoles from a temporary pond in southeastern Brazil (Amphibia, Anura). Revista Brasileira de Zoologia, 21, 745–754.

    Ruibal, R. & Thomas, E. (1988) The obligate carnivorous larvae of the frog Lepidobatrachus laevis (Leptodactylidae). Copeia, 1998, 591–604.

    Sandoval, M.T. (2000) Microanatomía del disco oral y cavidad bucofaríngea de la larva de Scinax acuminatus (Anura: Hylidae). Facena, 16, 93–101.

    Satel, S. & Wassersug, R.J. (1981) On the relative sizes of buccal floor depressor and elevator musculature in tadpoles. Copeia, 1981, 129–137.

    Savage, R.M. (1952) Ecological, physiological and anatomical observations on some species of anuran tadpoles. Proceedings of the Zoological Society of London, 122, 467–514.

    Savage, R.M. (1955) The ingestive, digestive and respiratory systems of the microhylid tadpole, Hypopachus aquae. Copeia, 1955, 120–127.

    Schiesari, L.C. (2004) Performance tradeoffs across resource gradients in anuran larvae.Ph.D. Dissertation, University of Michigan, USA.

    Schoener, W.T. (1969) Models of optimal size for solitary predators. American Naturalist, 103, 277–313.

    Schoener, W.T. (1971) Theory of feeding strategies. Annual Review of Ecology and Systematics, 2, 369–404.

    Seale, D. & Wassersug, R.J. (1979) Suspension feeding dynamics of anuran larvae related to their functional morphology. Oecologia, 39, 259–272.

    Sedra, S. (1951) The metamorphosis of the jaws and their muscles in the toad Bufo regularis Reuss, correlated with changes in the animal’s feedings habits. Proceedings of the Zoological Society of London, 120, 405–449.

    Sheil, C.A. & Alamillo, H. (2005) Osteology and skeletal development of Phyllomedusa vaillanti (Anura: Hylidae: Phyllomedusinae) and a comparison of this arboreal species with a terrestrial member of the genus. Journal of Morphology, 265, 343–368.

    Shoup, D.E. & Hill, L.G. (1997) Ecomorphological diet predictions: an assessment using inland silverside (Menidia beryllina) and longear sunfish (Lepomis megalotis) from Lake Texoma. Hydrobiologia, 350, 87–98.

    Sih, A. & Christensen, C. (2001) Optimal diet theory: when does it work, and when and why does it fail? Animal Behavior, 61, 379–390.

    Smith, M.A. (1916) Descriptions of five tadpoles from Siam. Journal of Natural History of Siam, 2, 37–43.

    Sokol, O.M. (1962) The tadpole of Hymenochirus boettgeri. Copeia, 1962, 272–284.

    Sokol, O.M. (1975) The phylogeny of anuran larvae: A new look. Copeia, 1975, 1–24.

    Sokol, O.M. (1977) The free swimming Pipa larvae, with a review of pipid larvae and pipid phylogeny (Anura: Pipidae). Journal of Morphology, 154, 357–426.

    Sokol, O.M. (1981) Larval chondrocranium of Pelodytes punctatus, with a review of tadpole chondrocrania. Journal of Morphology, 169, 161–193.

    SPSS for Windows (1998) Release 9.0.0. Copyright © SPSS Inc. 1989–1999.

    Starrett, P.H. (1960) Description of tadpoles of Middle America frogs. Miscellaneous Publications of the Museum of Zoology, University of Michigan, 110, 1–37.

    Starrett, P.H. (1968) The phylogenetical significance of the jaw musculature in anuran amphibians. Ph.D. Dissertation, University of Michigan, USA.

    STATISTICA. StatSoft, Inc. (2001) Data analysis software system. Version 6.

    Stayton, C.T. (2005) Morphological evolution of the lizard skull: a geometric morphometrics survey. Journal of Morphology, 263, 47–59.

    Steinwascher, K. & Travis, J. (1983) Influence of food quality and quantity on early larval growth of two anuran. Copeia, 1983, 238–242.

    Storz, B.L. (2004) Reassessment of the environmental mechanisms controlling developmental polyphenism in Spadefoot toad tadpoles. Oecologia, 141, 402–410.

    Swart, C.C. & De Sá, R.O. (1999) The chondrocranium of the Mexican burrowing toad, Rhinophrynus dorsalis (Anura: Rhinophrynidae). Journal of Herpetology, 33, 23–28.

    Svensson, M.E. & Haas, A. (2005) Evolutionary innovation in the vertebrate jaw: a derived morphology in anuran tadpoles and its possible developmental origin. BioEssays, 27, 529–532.

    Swiderski, D.L., Zelditch, M.L. & Fink. W.L. (1998) Why morphometrics is not special: coding quantitative data for phylogenetic analysis. Systematic Biology, 47, 508–519.

    Szalay, F.S. (2000) Function and adaptation in paleontology and phylogenetics: why do we omit Darwin? Palaeontologia Electronica, 3, 1–25.

    Taylor, C.L., Altig, R. & Boyle, C.R. (1995) Can anuran tadpoles choose among foods that vary in quality? Alytes, 13, 81–86.

    Terán, H.R. & Michel de Cerasuolo, A. (1988) Estudio histomorfológico del tracto digestivo larval de Gastrotheca gracilis Laurent (Anura: Hylidae). Neotropica, 36, 115–123.

    Ter Braak, C.J.F. (1986) Canonical correspondence analysis: A new eigenfactor technique for multivariate direct gradient analysis. Ecology, 67, 1167–1179.

    Ter Braak, C.J.F. & Smilauer, P. (1997) CANOCO for Windows Version 4.5. Copyright c 1997–2002. Biometrics – Plant Research International, Wageningen, The Netherlands.

    Tríbulo, C., Aybar, M.J., Sánchez, S.S. & Mayor, R. (2004) A balance between the anti-apoptotic activity of Slug and the apoptotic activity of msx1 is required for the proper development of the neural crest. Developmental Biology, 275, 325– 342.

    Trueb, L. & Hanken, J. (1992) Skeletal development in Xenopus laevis (Anura: Pipidae). Journal of Morphology, 214, 1–41.

    Ulloa Kreisel, Z.E. (2003) Estructuras con función digestiva en larvas de anfibios anuros del NOA. Ph.D. Dissertation, Universidad Nacional de Tucumán, Argentina.

    Van Buskirk, J. (2002) A comparative test of the adaptive plasticity hypothesis: relationships between habitat and phenotype in anuran larvae. American Naturalist, 160, 87–102.

    Vences, M., Puente, M., Nieto, S. & Vieites, D.R. (2002) Phenotypic plasticity of anuran larvae: environmental variables influence body shape and oral morphology in Rana temporaria tadpoles. Journal of Zoology of London, 257, 155–162.

    Vera Candioti, M.F. (2000) Mecanismos de alimentación en tres especies de hílidos (Amphibia: Anura) de la Provincia de Santa Fe. Pre-graduate Dissertation, Universidad Nacional del Litoral. Argentina.

    Vera Candioti, M.F. (2004) Morphology of premetamorphic larvae of Lysapsus limellus (Anura: Pseudinae) from Santa Fe, Argentina. Amphibia-Reptilia, 25, 41–54.

    Vera Candioti, M.F. (2005) Morphology and feeding in tadpoles of Ceratophrys cranwelli (Anura: Leptodactylidae). Acta Zoologica, 86, 1–11.

    Vera Candioti, M.F. (2006a) Ecomorphological guilds in anuran larvae: an application of geometric morphometric methods. Herpetological Journal, 16, 149–162.

    Vera Candioti, M.F. (2006b) Morfología larval de Chiasmocleis panamensis, con comentarios sobre la variabilidad morfológica interna en renacuajos de Microhylidae (Anura). Alytes, 24, 91–108.

    Vera Candioti, M.F. & Haas, A. (2004) Three dimensional reconstruction of the hyobranchial apparatus of Hyla nana tadpoles (Anura: Hylidae). Cuadernos de Herpetología, 18, 3–15.

    Vera Candioti, M.F. & Lajmanovich, R.C. (1998) Contribución al conocimiento de la alimentación de Phyllomedusa hypochondrialis azurea Cope, 1962 (Anura: Hylidae) en ambientes temporales de la Provincia de Santa Fe, Argentina. Boletín de la Sociedad Biológica de Concepción, Chile, 69, 203–209.

    Vera Candioti, M.F., Lavilla, E.O. & Echeverría, D.D. (2004) Feeding mechanisms in two treefrogs, Scinax nasicus and Hyla nana (Anura: Hylidae). Journal of Morphology, 261, 206–224.

    Vera Candioti, M.F., Úbeda, C. & Lavilla, E.O. (2005) Morphology and metamorphosis of Eupsophus calcaratus tadpoles (Anura: Leptodactylidae). Journal of Morphology, 264, 161–177.

    Vera Candioti, M.F., Brusquetti, F. & Netto, F. (2007) Morphological characterization of Leptodactylus elenae tadpoles (Anura: Leptodactylidae: L. fuscus group), from central Paraguay. Zootaxa, 1435, 1–17.

    Viertel, B. & Richter, S. (1999) Anatomy. Viscera and endocrines. In: McDiarmid, R.W. & Altig, R. (Eds.), Tadpoles. The biology of anuran larvae. University of Chicago Press, Chicago and London, pp. 92–148.

    Vincent, S.E, Moon, B.R., Shine, R. & Herrel. A. (2006) The functional meaning of ‘‘prey size’’ in water snakes (Nerodia fasciata, Colubridae). Oecologia 147: 204–211.

    Vizzoto, L.D. (1967) Desenvolvimiento de anuros da regiao norte occidental do Estado de Sao Paulo. Facultade de Filosofía Ciencias e Letras. Departamento de Zoología, Sao Paulo, Nro. especial, 1–161.

    Wainwright, P.C. & Richard, B.A. (1995) Predicting patterns of prey use from morphology with fishes. Environmental Biology of Fishes, 44, 97–113.

    Wassersug, R.J. (1972) The mechanism of ultraplanktonic entrapment in anuran larvae. Journal of Morphology, 137, 279–288.

    Wassersug, R.J. (1975) The adaptive significance of the tadpole stage with comments on the maintenance of complex life cycles in anurans. American Zoologist, 15, 405–417.

    Wassersug, R.J. (1976a) A procedure for differential staining of cartilage and bone in whole formaline fixed vertebrates. Stain Technology, 51, 131–134.

    Wassersug, R.J. (1976b) Oral morphology of anuran larvae: terminology and general description. Occasional Papers of the Museum of Natural History, University of Kansas, 48, 1–23.

    Wassersug, R.J. (1980) Internal oral features of larvae from eight anuran families. Functional, systematics, evolutionary and ecological considerations. Miscellaneous Publications of the Museum of Natural History, University of Kansas, 65, 1–146.

    Wassersug, R.J. (1984) The Pseudohemisus tadpole: a morphological link between microhylid (Orton Type 2) and Ranoid (Orton Type 4) larvae. Herpetologica, 40, 138–149.

    Wassersug, R.J. (1989) What, if anything is a microhylid (Orton Type II) tadpole? Fortschritte der Zoologie, 35, 534–538.

    Wassersug, R.J. & Heyer, W.R. (1988) A survey of internal oral features of leptodactyloid larvae (Amphibia: Anura). Smithsonian Contributions to Zoology, 457, 1–99.

    Wassersug, R.J. & Hoff, K. (1979) A comparative study of the buccal pumping mechanism of tadpoles. Biological Journal of the Linnean Society, 12, 225–259.

    Wassersug, R.J. & Hoff, K. (1982) Developmental changes in the orientation of the anuran jaw suspension. A preliminary exploration into the evolution of anuran metamorphosis. In: Hecht, M., Wallace, B. & Prace. G. (Eds.), Evolutionary Biology Volume 15. Plenum, New York, USA, pp. 223–246.

    Wassersug, R.J. & Pyburn, W.F. (1987) The biology of the Pe-ret’ toad, Otophryne robusta (Microhylidae), with special consideration of its fossorial larva and systematic relationships. Zoological Journal of the Linnean Society, 91, 137–169.

    Wassersug, R.J. & Rosenberg, K. (1979) Surface anatomy of branchial food traps of tadpoles. A comparative study. Journal of Morphology, 159, 393–426.

    Wassersug, R.J. & Yamashita, M. (2001) Plasticity and constraints on feeding kinematics in anuran larvae. Comparative Biochemistry and Physiology Part A, 131, 183–195.

    Weisz, P.C. (1945) The development and morphology of the larva of the South African clawed toad, Xenopus laevis. Journal of Morphology, 77, 163–217.

    Whiles, M.R., Lips, K.R., Pringle, C.M., Kilham, S.S., Bixby, R.J., Brenes, R., Connelly, S., Colon-Gaud, J.C., Hunte-Brown, M., Huryn, A.D., Montgomery, C. & Peterson, S. (2006) The effects of amphibian population declines on the structure and function of Neotropical stream ecosystems. Frontiers in Ecology and the Environment, 4, 27–34.

    Wilcox, D., Dove, B., McDavid, D. & Greer, D. (1995) UTHSCSA Image Tool. Version 1.28. University of Texas Health Sc Center San Antonio, USA.

    Wild, E.R. (1997a) Description of the adult skeleton and developmental osteology of the hyperossified Horned frog, Ceratophrys cornuta (Anura: Leptodactylidae). Journal of Morphology, 232, 169–206.

    Wild, E.R. (1997b) The ontogeny and phylogeny of ceratophryine frogs (Anura: Leptodactylidae). Ph.D. Dissertation, University of Kansas, USA.

    Wild, E.R. (1999) Description of the chondrocranium and osteogenesis of the Chacoan burrowing frog, Chacophrys pierotti (Anura: Leptodactylidae). Journal of Morphology, 242, 229–246.

    Winkler, H. (2002) Ecomorphology and the form-function complex. Journal of Morphology, 248, 301. In: Abstracts of Sixth International Congress of Vertebrate Morphology. Jena, Germany.

    Zelditch, M.L. & Fink, W.L. (1998) Partial warps, phylogeny and ontogeny: a reply to Adams and Rosenberg. Systematic Biology, 47, 345–348.

    Zelditch, M.L., Swiderski, D.L., Sheets, H.D. & Fink, W.L. (2004) Geometric Morphometrics for Biologists, Elsevier Academic Press, San Diego, USA.