The evidentiary basis of the currently accepted classification of living amphibians is discussed and shown not to warrant the degree of authority conferred on it by use and tradition. A new taxonomy of living amphibians is proposed to correct the deficiencies of the old one. This new taxonomy is based on the largest phylogenetic analysis of living Amphibia so far accomplished. We combined the comparative anatomical character evidence of Haas (2003) with DNA sequences from the mitochondrial transcription unit H1 (12S and 16S ribosomal RNA and tRNAValine genes, ≈ 2,400 bp of mitochondrial sequences) and the nuclear genes histone H3, rhodopsin, tyrosinase, and seven in absentia, and the large ribosomal subunit 28S (≈ 2,300 bp of nuclear sequences; ca. 1.8 million base pairs; x = 3.7 kb/terminal). The dataset includes 532 terminals sampled from 522 species representative of the global diversity of amphibians as well as seven of the closest living relatives of amphibians for outgroup comparisons. The...

https://bioone.org/journals/Bulletin-of-the-American-Museum-of-Natural-History/volume-2006/issue-297/0003-0090(2006)297[0001:TATOL]2.0.CO;2/THE-AMPHIBIAN-TREE-OF-LIFE/10.1206/0003-0090(2006)297[0001:TATOL]2.0.CO;2.pdf

The amphibian tree of life

http://home.gwu.edu/~rpyron/publications/Pyron_Wiens_2011.pdf

A large-scale phylogeny of Amphibia including over 2800 species, and a revised classification of extant frogs, salamanders, and caecilians

▪ Abstract Declines and losses of amphibian populations are a global problem with complex local causes. These may include ultraviolet radiation, predation, habitat modification, environmental acidity and toxicants, diseases, changes in climate or weather patterns, and interactions among these factors. Understanding the extent of the problem and its nature requires an understanding of how local factors affect the dynamics of local populations. Hypotheses about population behavior must be tested against appropriate null hypotheses. We generated null hypotheses for the behavior of amphibian populations using a model, and we used them to test hypotheses about the behavior of 85 time series taken from the literature. Our results suggest that most amphibian populations should decrease more often than they increase, due to highly variable recruitment and less variable adult mortality. During the period covered by our data (1951–1997), more amphibian populations decreased than our model predicted. However, there ...

/pdf/global-amphibian-declines-a-problem-in-applied-ecology-22m177jgsq.pdf

Global Amphibian Declines: A Problem in Applied Ecology

Amniote phylogeny and the importance of fossils

Hylidae is a large family of American, Australopapuan, and temperate Eurasian treefrogs of approximately 870 known species, divided among four subfamilies. Although some groups of Hylidae have been addressed phylogenetically, a comprehensive phylogenetic analysis has never been presented. The first goal of this paper is to review the current state of hylid systematics. We focus on the very large subfamily Hylinae (590 species), evaluate the monophyly of named taxa, and examine the evidential basis of the existing taxonomy. The second objective is to perform a phylogenetic analysis using mostly DNA sequence data in order to (1) test the monophyly of the Hylidae; (2) determine its constituent taxa, with special attention to the genera and species groups which form the subfamily Hylinae, and c) propose a new, monophyletic taxonomy consistent with the hypothesized relationships. We present a phylogenetic analysis of hylid frogs based on 276 terminals, including 228 hylids and 48 outgroup taxa. Includ...

/pdf/systematic-review-of-the-frog-family-hylidae-with-special-40f16i0lsj.pdf

Systematic review of the frog family hylidae, with special reference to hylinae: phylogenetic analysis and taxonomic revision

Introduction to amphibia - the world of amphibians, historical resume, prospects for the future. Part 1 Life History: reproductive strategies - reproductive cycles, reproductive mode, quantitative aspects, parental care, evolution of reproductive strategies courtship and mating - location of breeding site, secondary sexual characters, courtship behaviour, fertilization and oviposition, sexual selection, evolution of mating systems vocalization - anuran communication system, mechanisms of sound production and reception, kinds of vocalizations and their functions, abiotic factors affecting vocalization, interspecific significance of vocalization, phylogenetic implications of vocalization eggs and development - spermatozoa and fertilization, egg structure, egg development, hatching and birth, development and amphibian diversity larvae - morphology of larvae, adaptive types of larvae, physiology and ecology, social behaviour, evolutionary significance of larvae metamorphosis - endocrine control, other biochemical changes, morphological changes, neoteny, ecological and evolutionary significance of metamorphosis. Part 2 Ecology: relationships with the environment - water economy, temperature, gas exchange, energy metabolism and energy budgets, ecological synthesis food and feeding - prey selection, location of prey, capture of prey, evolution of prey-capturing mechanisms and strategies enemies and defence - diseases, parasites, predators, anti-predator mechanisms, evolution of defence mechanisms population biology - characteristics of individuals, movements and territoriality, demography, factors regulating populations community ecology and species diversity - community structure, species diversity, evolution of amphibian communities. Part 3 Morphology: musculoskeletal system - skull and hyobranchium, axial system, appendicular system, integration of functional units integumentary, sensory and visceral systems - integument, sensory receptor systems, nervous system, circulatory and respiratory systems, urogenital system, digestive system, endocrine glands, evolutionary considerations. Part 4 Evolution: origin and early evolution - nature of a tetrapod, primitive tetrapods, tetrapod affinities (lungfishes or lobe-fins?), diversity and evolution of early tetrapods, status of the lissamphibia cytogenetic, molecular and genomic evolution - cytogenetics, molecular evolution, genomic evolution phylogeny - caudata, gymnophiona, anura biogeography - biogeographic principles, historical setting, lissamphibia, caudata, gymnophiona, anura classification.

Biology of Amphibians

Based on a molecular phylogeny, a new phylogenetic taxonomy that is compatible with both the International Code of Zoological Nomenclature (ICZN) and the PhyloCode is proposed for Glassfrogs and ...

/pdf/phylogenetic-systematics-of-glassfrogs-amphibia-40zibougvd.pdf

Phylogenetic systematics of Glassfrogs (Amphibia: Centrolenidae) and their sister taxon Allophryne ruthveni

Postembryonic skeletal development of the pipid frog Xenopus laevis is described from cleared-and-stained whole-mount specimens and sectioned material representing Nieuwkoop and Faber developmental Stages 46–65, plus postmetamorphic individuals up to 6 months old. An assessment of variation of skeletogenesis within a single population of larvae and comparison with earlier studies revealed that the timing, but not the sequence, of skeletal development in X. laevis is more variable than previously reported and poorly correlated with the development of external morphology. Examination of chondrocranial development indicates that the rostral cartilages of X. laevis are homologous with the suprarostral cartilages of non-pipoid anurans, and suggests that the peculiar chondrocranium of this taxon is derived from a more generalized pattern typical of non-pipoid frogs. Derived features of skeletal development not previously reported for X. laevis include (1) bipartite formation of the palatoquadrate; (2) precocious formation of the adult mandible; (3) origin of the angulosplenial from two centers of ossification; (4) complete erosion of the orbital cartilage during the later stages of metamorphosis; (5) development of the sphenethmoid as a membrane, rather than an endochondral bone; and (6) a pattern of timing of ossification that more closely coincides with that of the pelobatid frog Spea than that recorded for neobatrachian species. © 1992 Wiley-Liss, Inc.

Skeletal development in Xenopus laevis (Anura: Pipidae).

Evolution of pipoid frogs intergeneric relationships of the aquatic frog family pipidae anura

Three frogs of a new species found in cloud forests on two nearby mountains in Guyana were included in a molecular phylogeny of 17 nuclear and mitochondrial genes (10,739 aligned sites) that revealed that their closest relative is Terrarana (Brachycephalidae, Craugastoridae, Eleutherodactylidae, and Strabomantidae) and their next-closest relative is Hemiphractidae (marsupial frogs). We place these frogs in a new family, genus, and species which is strongly supported as the basal clade within Terrarana: Ceuthomantidae n. fam., Ceuthomantis smaragdinus n. gen, n. sp. Morphological evidence supports the placement of two other species from the Guiana Highlands, Pristimantis aracamuni (BarrioAmoros & Molina) and P. cavernibardus (Myers & Donnelly), in the new family and genus. This close phylogenetic relationship of terraranans and marsupial frogs, nearly all of which have direct development, supports an hypothesis that direct development evolved early in the evolution of this huge clade (~1000 species), for which we propose the unranked taxonomic epithet Orthobatrachia.

Linda Trueb

Papers

Biology of Amphibians

Phylogenetic systematics of Glassfrogs (Amphibia: Centrolenidae) and their sister taxon Allophryne ruthveni

Skeletal development in Xenopus laevis (Anura: Pipidae).

Evolution of pipoid frogs intergeneric relationships of the aquatic frog family pipidae anura

A new frog family (Anura: Terrarana) from South America and an expanded direct-developing clade revealed by molecular phylogeny