Abstract

The phylogenetic relationships of genera of the family Centrarchidae and its affinities to the Elassomatidae were examined using the mitochondrial DNA sequences of the cytochrome b gene. A total of 32 individuals representing 16 species from nine genera of centrarchids were sequenced. Outgroup were drawn from other perciform families including several families previously proposed to be closely related to the Centrarchidae. Phylogenetic analysis was conducted using the optimality criteria of maximum parsimony with two weighting schemes and using the maximum likelihood method. A priori and a posteriori alternative hypotheses of relationships within the Centrarchidae were investigated using the Shimodaira and Hasegawa Test. The results of all analyses support the monophyly of the Centrarchidae, although the interrelationships of centrarchid genera differed between analyses. Elassoma was never recovered as the sister taxon to the Centrarchidae; however, the sister relationship of these taxa could not be rejected. Additional data are required to unambiguously resolve relationships among centrarchid genera and determine the relationship of the Centrarchidae to other perciforms.

Abstract

The Homalopsinae (Oriental-Australian rear-fanged water snakes) is a small (34 species, 10 genera) colubrid subfamily notable for its ecological and morphological diversity. Despite considerable interest in the ecology and evolution of this group, phylogenetic relationships within the subfamily are poorly resolved. We present the results of a molecular phylogenetic study of the homalopsines based on partial sequence of three mitochondrial genes (12S and 16S ribosomal RNA and cytochrome b) from 14 ingroup species, five Old and New World natricines and the Old World colubrid, Dinodon semicarinatus. Maximum likelihood analysis in combination with bootstrapping and Bayesian Markov chain Monte Carlo methods for assessing phylogenetic confidence revealed that the single most likely topology contained a number of well-supported nodes. Homalopsine monophyly was strongly supported with respect to the outgroups included in our study. Cantoria violacea, a morphologically distinctive marine crustacean eater, formed the sister group to the rest of the homalopsines. Enhydris, the most species-rich genus in the subfamily, was polyphyletic with respect to other homalopsines although five morphologically and ecologically similar species formed a well-supported clade. The marine crustacean eaters Fordonia leucobalia and Gerarda prevostiana, also formed a novel clade. We discuss the evolutionary and ecological implications of this phylogeny for the Homalopsinae.

Abstract

Phylogenetic relationships among taxa of the annual fish subtribe Cynolebiatina are examined, based on 57 morphological characters in 29 terminal taxa, including two basal species of the well-supported monophyletic genus Cynolebias Steindachner, 19 valid species of Austrolebias Costa, and all five valid species of Megalebias Costa. A clade comprising Austrolebias and Megalebias is strongly supported (bootstrap value 96%) and defined by five nonhomoplastic synapomorphies: deep urohyal, long cleithrum, dorsal and anal fins of male short and rounded, frontal squamation F-patterned, and a transverse supraorbital bar. Monophyly of Megalebias is supported (bootstrap value 98%) by 12 synapomorphies, four unambiguous: reduced basihyal, anteriorly expanded anterolateral tip of lateral process of sphenotic, curved lacrimal, and posteroventrally directed suborbital stripe. Monophyly of Austrolebias (bootstrap value 96%) is corroborated by a reduced basihyal ossification, a laterally expanded basihyal cartilage, an anteriorly positioned dorsal fin of male, and a spotted color pattern in female. Evidence supporting intergeneric and intrageneric relationships is discussed.

Relações filogenéticas entre taxa da subtribo de peixes anuais Cynolebiatina são examinadas, com base em 57 caracteres morfológicos em 29 taxa terminais, incluindo duas espécies basais do bem corroborado gênero monofilético Cynolebias, 19 espécies válidas de Austrolebias Costa, e todas as cinco espécies válidas de Megalebias Costa. Um clado compreendendo Austrolebias e Megalebias é fortemente sustentado (valor de bootstrap 96%), e definido por cinco sinapomorfias não homoplásticas: uro-hial alto, cleitro longo, nadadeiras dorsal e anal de macho curtas e arredondadas, escamação frontal em padrão F, e uma barra supraorbital transversal. Monofiletismo de Megalebias é sustentado (valor de bootstrap 98%) por 12 sinapomorfias, quatro não ambíguas: basi-hial reduzido, ponta antero-lateral de esfenótico expandida anteriormente, lacrimal encurvado, e faixa suborbital direcionada postero-ventralmente. Monofiletismo de Austrolebias (valor de bootstrap 96%) é corroborado pela reduzida ossificação do basi-hial, expansão lateral de cartilagem basi-hial, nadadeira dorsal de macho posicionada anteriormente, e padrão de colorido maculado em fêmea. Evidências sustentando relações inter e intra-genéricas são discutidas.

THE AMPHIBIANS OF HONDURAS. James R. McCranie and Larry David Wilson. 2002. Society for the Study of Amphibians and Reptiles, Ithaca, New York. ISBN 0-916984-57-5. 625 p. $62.00 (hardcover).—Monographs represent major contributions to knowledge regarding specific taxonomic groups, biogeographic regions, or, as in this case, a country. This book fulfills that general expectation, and represents a true advance in our understanding of Mesoamerican amphibians. Although the authors' publications over the years contain information on various newly described species from Honduras, here finally is our chance to see information on all species, complete with the dot maps, and ecological notes. Yes,

Redescription of Apostolepis sanctaeritae Werner 1924 (Serpentes, Colubridae), and a Comparison with Related Species