On a Remarkable Blind Siluroid Fish of the Family Clariidae from Kerala (India)

Evolution in the dark: Unexpected genetic diversity and morphological stasis in the blind, aquifer-dwelling catfish Horaglanis

“…Specimens are deposited in the museum collection of Kerala University of Fisheries and Ocean Studies (KUFOS), Kochi, India. Characterization and analysis of morphometric and meristic information follow methods described in the original descriptions of the three species of Horaglanis (Menon 1951;Babu and Nayar 2004;Babu 2012), with the addition of several characters. Size adjusted multivariate morphometric data, expressed as percentage of standard length, were plotted using Principal Component Analysis (PCA) and the null hypothesis that there was no significant difference in the morphometric data among species was tested using PERMANOVA (Ander-son 2001).…”

“…Specimens of Horaglanis have hitherto been collected only from homestead dug-out wells (5-10 m deep) across the laterite soil formations in Kerala State, to which the genus is endemic. As a consequence of these unique sampling circumstances, Horaglanis was, until recently, known from only seven localities (Menon 1951;Mercy 1981;Babu and Nayar 2004;Babu 2012;Vincent 2012). Over the course of our study, we obtained 47 new vouchered location records for this genus (Fig.…”

“…1C), paucity of museum specimens (known until recently just from a handful of examples), and unresolved phylogenetic and biogeographic affinities (Menon 1951;de Pinna 1993). Though three species are currently known (Horaglanis krishnai Menon, 1951, H. alikunhii Subhash Babu & Nair, 2004, H. abdulkalami Subhash Babu, 2012, the latter two were poorly described; the taxonomic and geographic boundaries between the three species have thus remained unclear. Fewer than ten published records of Horaglanis backed by voucher specimens are available (Fig.…”