Gelanoglanis pan can be distinguished from all congeners by the following characters: anterior middorsal fontanel situated between the anterior portions of the contralateral frontals present (vs. the frontals conjoined along the entirely of their middorsal margins and the fontanel

absent); long fleshy, tubular gonopodium extending posteriorly to a point midway along the length of the anal fin in adult males (vs. the gonopodium reaching only to, or slightly beyond, the anal-fin origin in G. travieso and G. stroudi or falling short of the anal-fin

origin in G. nanonocticolus); and deeper caudalpeduncle 12.1-13.5% SL (vs. 9.5-12.0% in G. stroudi, 10.2-11.6% in G. nanonocticolus, and 9.4-11.7% in G.

travieso). It can be diagnosed G. stroudi and G. travieso by the following characters: premaxillary teeth occupying one-half or less of length of premaxilla and restricted to the its more vertically expansive anterior portion (vs. the teeth distributed along most of the dentigerous margin of premaxilla and occupying two-thirds of length of the bone); the portion of the maxilla inside the base of the maxillary barbel shorter and terminating posteriorly forward of the anterior margin of the opercle (vs. maxilla terminating posteriorly to the middle of the opercle); and larger orbital diameter 14.4-17.9% HL (vs. 7.2-9.3% in G. stroudi and 8.2-12.8% in G. travieso). It further differs from G. nanonocticolus by the presence of well-developed serrae on pectoral- and dorsal-fin spines (vs. vs. absence).