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Issue: Vol. 5839 No. 3: 30 Jun. 2026
Type: Article
Published: 2026-06-30
DOI: 10.11646/zootaxa.5839.3.3
Page range: 470-482
Abstract views: 127
PDF downloaded: 4

Redescription of Mystus oculatus (Valenciennes, 1840), a senior synonym of Mystus armatus (Day, 1865) (Teleostei: Bagridae)

Independent Researcher; Mumbai; Maharashtra; India–400072
Wildlife Institute of India; Chandrabani; Dehradun; Uttarakhand; India–248001
Pisces Siluriformes bagrid catfish Kerala Western Ghats species groups

Abstract

Mystus oculatus (Valenciennes, 1840) is redescribed based on putative topotypes. It differs from congeners known from the Indian subcontinent in possessing the following combination of characters: live colouration consisting of prominent black blotch at the base of dorsal-fin spine, pale longitudinal stripes above and below lateral line, diffuse humeral blotch and a sub-triangular midpeduncular blotch; cranial fontanel almost reaching base of supraoccipital process; short adipose-fin base not reaching base of last dorsal-fin ray anteriorly; adipose-fin base 15.2–16.8 % SL; caudal peduncle depth 8.5–10.4 % SL; eye diameter 22.2–32.1 % HL and dorsal to adipose distance 17.3–23.4 % SL. The taxonomic status of Mystus armatus, here considered a junior synonym of Mystus oculatus, is clarified. Five species groups are proposed and defined for South Asian Mystus.

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How to Cite

Vijayakrishnan, B. & Shinde, G.A. (2026) Redescription of Mystus oculatus (Valenciennes, 1840), a senior synonym of Mystus armatus (Day, 1865) (Teleostei: Bagridae). Zootaxa, 5839 (3), 470–482. https://doi.org/10.11646/zootaxa.5839.3.3