Differs from all its congeners, except P. doriae and P. pulla, by the number of abdominal vertebrae. Can be differentiated from P. pulla by the presence of pelvic girdle and fins (vs. absence) and the plain light brown coloration (vs. blackish brown with 20-25 narrow vertical bars), and from P. doriae by the absence of a nasal barbel (vs. presence) and fewer caudal vertebrae (13-15 vs. 15-18). Can be distinguished further from the Myanmar species of Pangio with pelvic girdle and fins by the position of the basipterygia relative to the vertebral column (at level of vertebra 33 vs. at level of vertebra 29 in P. signicauda and P. lumbrici[ormis, and at level of vertebra 23-24 in P. pangia), from P. signicauda and P. lumbriciformis by the uniform, plain brown coloration (vs. color pattern with dark marks on body and fins), from P. fusca and P. pangia by the more slender, elongate body (body depth 7.8 % SL vs. 8.7-12.0 in P. pangia and 13.5-16.3 in P. fusca) and narrower (caudal peduncle depth 5 % SL vs. 5.9-9.7) and longer caudal peduncle (14.9 % SL vs. 9.5-12.5), from P. fusca by the presence of pelvic fins and girdle (vs. absence) and the absence of a nasal barbel (vs. presence), and from P. pangia by a more slender body (body depth 7.8 % SL vs. 13.5-16.3), shorter pectoral fin (5.3 % SL vs. 8.2-9.6) and relatively more anteriorly placed pelvic fins (prepelvic length 56.3 % SL vs. 79.0-86.8) (Ref. 57993).