A new syntopic species of small barb from the Western Ghats of India (Teleostei: Cyprinidae)

Abstract

A new species of the cyprinid genus Pethia is described from the Hiranyakeshi, a tributary of the Krishna River system in the Western Ghats mountain ranges of peninsular India. The new species, Pethia sahit, is syntopic—and shoals together—with Pethia longicauda, a species described recently from the same river. Pethia sahit is distinguished from P. longicauda and its congeners by a combination of characters like, incomplete lateral line with 3–6 pored scales; 19–22 scales in lateral series; 4½ scales between dorsal-fin origin and lateral-line row and 2½ scales between lateral line row and pelvic-fin origin; intercalated scale row originates above and after the 6th scale of the lateral-line scale row; dorsal fin originating behind the pelvic-fin origin; 4+13 abdominal and 12 caudal vertebrae; dorsal, pectoral, pelvic, anal and caudal fins without any bands or spots, deep yellow-orange in color or deep red with a pale tint of orange in mature males; a dark-black vertically elongate humeral spot, overlapping the 4th lateral-line scale, extending over the base of one scale above and below the 4th scale; caudal peduncle spot dark, covering 14th–16th scales in lateral-line scale row. Genetic analysis based on the mitochondrial cytochrome b gene indicates that P. sahit and P. longicauda are not sister taxa. Further, P. sahit has no genetically proximate congener in the Western Ghats region, and differs from known congeners from south and southeast Asia, for which genetic data are available, with genetic distance ranging from 11.8–16.4%.

Molecular phylogeny and systematics of the South Asian freshwater‐fish genus Puntius (Teleostei: Cyprinidae)

“…As also noted by Ren et al (2020), Puntius paucimaculatus and P. snyderi may, in fact, belong to lineages outside Smiliogastrinae. Several such well‐distinguished lineages have been identified also in other well‐explored Asian smiliogastrine groups, such as in Pethia (Conway et al, 2021; Katwate et al, 2018; Sudasinghe et al, 2021b).…”

Molecular phylogeny and phylogeography of the freshwater-fish genus Pethia (Teleostei: Cyprinidae) in Sri Lanka

“…castor’, and ‘P. pollux’ are morphologically so distinct from Pethia sensu stricto and other Smiliogastrini that they may warrant placement in different genera [ 16 , 18 , 19 ]. The original description by Hora [ 36 ] of ‘ Pethia’ narayani does not mention a serrated last unbranched dorsal-fin ray, which is a synapomorphy in Pethia.…”

“…The comparative genetic dataset representative of Smiliogastrinae based on Sudasinghe et al [ 11 ], together with additional sequences generated by Katwate et al [ 57 ], Katwate et al [ 37 ], Ren et al [ 25 ] and Sudasinghe et al [ 10 ], were compiled and used in the present study (Additional file 1 : Table S2). Among the 16 valid species of Pethia from Sri Lanka and peninsular India, 13 are represented in our cytb dataset, based on reliably identified specimens [present study; 16 , 19 , 23 , 24 , 28 , 30 , 31 , 58 ]. This reference dataset thus allowed us to confidently identify some incorrectly identified or dubious GenBank sequences.…”

“…The only three species of Pethia from the Indian peninsula not represented in our dataset are P. narayani , P. sharmai and P. striata . Of these, the generic placement of the first two is doubtful [see Discussion ; also 16 , 19 ]. Unfortunately, we lack a nuclear ( rag1 ) reference dataset, based on reliably identified specimens, of Indian Pethia .…”

“…The cyprinid genus Pethia presently includes some 43 valid species (Additional file 1: Table S1), nine of which have been discovered since the genus was first described by Pethiyagoda et al [16] [see : 17]. Pethia have a wide distribution, ranging from Sri Lanka across India and on to Myanmar [16,[18][19][20][21]. They are colorful, usually sexually dimorphic fishes that have long been popular in the global ornamental-fish trade [22].…”