RESUMO
The phylogenetic relationships of the African mongrel frog genus Nothophryne are poorly understood. We provide the first molecular assessment of the phylogenetic position of, and diversity within, this monotypic genus from across its range-the Afromontane regions of Malawi and Mozambique. Our analysis using a two-tiered phylogenetic approach allowed us to place the genus in Pyxicephalidae. Within the family, Nothophryne grouped with Tomopterna, a hypothesis judged significantly better than alternative hypotheses proposed based on morphology. Our analyses of populations across the range of Nothophryne suggest the presence of several cryptic species, at least one species per mountain. Formal recognition of these species is pending but there is a major conservation concern for these narrowly distributed populations in an area impacted by major habitat change. The phylogenetic tree of pyxicephalids is used to examine evolution of life history, ancestral habitat, and biogeography of this group.
Assuntos
Anuros/classificação , Variação Genética , Filogenia , Animais , Cruzamento , Ecossistema , Geografia , Modelos Teóricos , Moçambique , Especificidade da Espécie , Fatores de TempoRESUMO
The family Pyxicephalidae including two subfamilies (Cacosterninae and Pyxicephalinae) is an ecologically important group of frogs distributed in sub-Saharan Africa. However, its phylogenetic position among the Anura has remained uncertain. The present study determined the complete mitochondrial genome sequence of Pyxicephalus adspersus, the first representative mitochondrial genome from the Pyxicephalinae, and reconstructed the phylogenetic relationships within Ranoidae using 10 mitochondrial protein-coding genes of 59 frog species. The P. adspersus mitochondrial genome showed major gene rearrangement and an exceptionally long length that is not shared with other Ranoidae species. The genome is 24,317 bp in length, and contains 15 protein-coding genes (including extra COX3 and Cyt b genes), four rRNA genes (including extra 12S rRNA and 16S rRNA genes), 29 tRNA genes (including extra tRNALeu (UAG), tRNALeu (UUR), tRNAThr , tRNAPro , tRNAPhe , tRNAVal , tRNAGln genes) and two control regions (CRs). The Dimer-Mitogenome and Tandem duplication and random loss models were used to explain these gene arrangements. Finally, both Bayesian inference and maximum likelihood analyses supported the conclusion that Pyxicephalidae was monophyletic and that Pyxicephalidae was the sister clade of (Petropedetidae + Ptychadenidae).
RESUMO
Rhabdias picardiae previously known from the Guttural Toad, Sclerophrys gutturalis (Bufonidae) is described from a new host, Delaland's River Frog, Amietia delalandii (Pyxicephalidae). The species identification is confirmed by analysis of the COI gene sequence and morphological comparison with the original description. Morphological details of apical structures in adult parasitic R. picardiae, namely, the shape and position of lips, the number and position of external labial papillae, and the buccal capsule morphology are described using light and scanning electron microscopy. The buccal capsule width and length, the distance from anterior end to nerve ring and excretory pore, and ratios of distance to vulva to body length and body length to width were identified as less variable metrical characters in the studied sample of 30 specimens. Adult specimens demonstrated differences in the position of lips in relation to the oral opening and position of the buccal capsule in relation to the oesophagus depending on the size (age) of worms. The infective larvae of R. picardiae are described for the first time and characterised by two lateral alae consisting of two ridges, triangular pseudolabia with rounded tops, and presence of ornamentation on the rounded tail tip.