Abstract
Ompok platyrhynchus, a new species of silurid catfish is described from the Temburong River drainage in Brunei Darussalam, northern Borneo. Ompok platyrhynchus can be distinguished from all Southeast Asian congeners, except for O. hypophthalmus, O. rhadinurus and O. urbaini, in having 74 80 (vs. 40 70) anal-fin rays. Ompok platyrhynchus differs from O. hypophthalmus, O. rhadinurus and O. urbaini in lacking a distinct nuchal concavity, having a more slender body (13.5 17.7% SL vs. 18.9 24.5), shorter snout (37.1 38.1% HL vs. 39.4 47.5) and maxillary barbels (reaching to middle of pectoral fin vs. reaching to anterior third of anal fin), and more vertebrae (59 60 vs. 47 58).References
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