The phylogenetic relationships of Yunganastes revisited (Anura: Terrarana)

Abstract

1. IntroductionIn this study, we reanalyze the phylogenetic relationships of thesubgenusYunganastes,agroupofCentralAndeandirect-developingfrogs with five described species (Padial et al., 2007). The phyloge-netic relationships of Yunganastes remain contentious. Members ofthis taxon were for a long time considered Eleutherodactylus (Lynchand McDiarmid, 1987; De la Riva and Lynch, 1997; Kohler, 2000).Subsequently, they were included in the Middle American subge-nus Craugastor, despite their disjunct distributions, because ashared condition of the trigeminal nerve (De la Riva and Lynch,1997). Kohler (2000) formally grouped four of the five species ofYunganastes in the Eleutherodactylus fraudator species group, stillwithin the subgenus Craugastor. Crawford and Smith (2005) usedmoleculardatatoanalyzethephylogeneticrelationshipsandbioge-ography of the subgenus Craugastor and raised it to the genus level,but these authors did not include members of the E. fraudator spe-cies group in their data set. Frost et al. (2006) compared the condi-tionofthetrigeminalnerveinamemberoftheE.fraudatorgroup(E.pluvicanorus) and found differences with Craugastor. They removedtheE.fraudatorgroupfromCraugastorandplaceditwithinthenon-monophyleticsubgenusEleutherodactylus.Padialetal.(2007)madea comprehensive taxonomic revision of the group, included onemore species (E. mercedesae), and found that the condition de-scribed by Frost et al. (2006) was shared by all members of thegroup but not by Craugastor or Eleutherodactylus. Additionally, Pa-dial et al. (2007) presented phylogenetic analyses of a short frag-ment (560 bp) of the 16S mtDNA that further supported themonophyly of the group, placing it outside the Central AmericanCraugastor and more closely related to other ‘‘Eleutherodactylus”from South America. They formally described the group as the sub-genus Yunganastes within the non-monophyletic ‘‘Eleutherodacty-lus”. More recently, Hedges et al. (2008) presented a taxonomicreviewofTerrarana(anamethatreferstoacladethatencompassescirca 900 species of New World direct-developing frogs, includingYunganastes) based on three molecular trees with different taxon(80, 216 and 362 species) and character sampling (1207, 2578and 3709 bp). They placed most South American ‘‘Eleutherodacty-lus”, including members of Yunganastes, in the genus Pristimantis(427 spp.). They also analyzed a short ( 500 bp) sequence of a rep-resentative species of Yunganastes (Pristimantis pluvicanorus) andfoundthatitwasbasaltoPristimantis,althoughsupportlevelswerelow and the resulting topologywas not shown. Hedges et al. (2008)tentatively placed Yunganastes within the large genus Pristimantis,but recommended to analyze additional sequence data to assessthe relationships of this taxon.Here, we study the evolutionary relationships of Yunganasteswithin Terrarana based on Bayesian and maximum likelihood phy-logenetic analyses (BA and ML, respectively). We analyze a matrixof 1300 base pairs of the 16S and 12S mtDNA genes for a total of375 terminals. Ingroup sampling includes sequences from all fivespecies of Yunganastes, plus eight species of Oreobates, seven of