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Frogs of the genus Minervarya are cryptic and widely distributed in South Asia. However, many of them lack information about the precise type locality, genetic data, and distribution range. The present study aimed to examine the genetic affinities of a widely distributed species Minervarya syhadrensis around its type locality in the northern Western Ghats (Pune, Maharashtra). We studied the type specimen of M. syhadrensis and collected similar sized Minervarya frogs from Pune district. In the field, we observed two different calls from morphologically similar (M. syhadrensis like) males suggesting the sympatric occurrence of two cryptic species (that we initially named Minervarya species A and Minervarya species B). We analyzed morphology, call pattern, and mitochondrial 16S rRNA gene sequence of both species. Minervarya species A has a long call with a low pulse repetition rate and higher dominant frequency compared to that of the Minervarya species B. These species cannot be differentiated based on morphometric data. However, they can be sorted out using morphological characters such as the presence of longitudinal skin folds on the dorsal side (Minervarya species A) and differences in foot webbing. DNA sequences of Minervarya species A and Minervarya species B are matching with those of M. caperata and M. agricola respectively. After studying the type specimens of M. syhadrensis and M. caperata, we found morphological similarities (longitudinal skin folds) with the samples of Minervarya species A collected during the present study. Based on the results of our study (morphology and genetic) and available literature, we propose to redefine M. syhadrensis as applying to the lineage initially named Minervarya species A, and to treat the species M. caperata as a junior synonym of M. syhadrensis. Our study will be helpful in further taxonomic revision of the genus, and provides natural history information for M. syhadrensis and M. agricola.

The cytolytic activity of the membrane attack complex (MAC) has a crucial role in the complement-mediated elimination of pathogens. Terminal complement pathway (TCP) genes encode the proteins that form the MAC. Although the TCP genes are well conserved within most vertebrate species, the early evolution of the TCP genes is poorly understood. Based on the comparative genomic analysis of the early evolutionary history of the TCP homologs, we evaluated four possible scenarios that could have given rise to the vertebrate TCP. Currently available genomic data support a scheme of complex sequential protein domain gains that may be responsible for the birth of the vertebrate C6 gene. The subsequent duplication and divergence of this vertebrate C6 gene formed the C7, C8α, C8β, and C9 genes. Compared to the widespread conservation of TCP components within vertebrates, we discovered that C9 has disintegrated in the genomes of galliform birds. Publicly available genome and transcriptome sequencing datasets of chicken from Illumina short read, PacBio long read, and Optical mapping technologies support the validity of the genome assembly at the C9 locus. In this study, we have generated a >120X coverage whole-genome Chromium 10x linked-read sequencing dataset for the chicken and used it to verify the loss of the C9 gene in the chicken. We find multiple CR1 (chicken repeat 1) element insertions within and near the remnant exons of C9 in several galliform bird genomes. The reconstructed chronology of events shows that the CR1 insertions occurred after C9 gene loss in an early galliform ancestor. Our study of C6 gene birth in an early vertebrate ancestor and C9 gene death in galliform birds provides insights into the evolution of the TCP.