This species is distinguished from its congeners in Sundaland except for G. decussatus, G. major, G. plectilis in having (vs. lacking) anteromedial striae in the thoracic adhesive apparatus; differs from G. decussatus in lacking (vs. having) a dark vertical bar at the base of the caudal fin in the shape of an irregular cross; differs from G. major in having the anterolateral edges of the thoracic adhesive apparatus almost straight (vs. markedly concave) and a deeper caudal peduncle 9.8-11.2% SL (vs. 7.7-10.1); differs from G. plectilis in having an oblong thoracic adhesive apparatus with almost straight anterolateral edges (vs. ovate with gently convex anterolateral edges) and non-prominent tubercles of uniform size (vs. with prominent, enlarged tubercles) along the flanks; its unique combination of characters further distinguishes this species from Sundaic congeners: approximately half of premaxillary toothband exposed when mouth is closed; eye diameter 6-10% HL; head width 19.9-23.0% SL; margin of dorsal fin concave; dorsal to adipose distance 17.9-23.4% SL; maximum height of adipose fin 2.2-2.6 times in its length, straight dorsoposterior margin of adipose fin; body depth at anus 15.3-20.6% SL; post-adipose distance 15.8-19.7% SL; caudal peduncle depth 1.4-2.2 times in its length and 1.4-2.1 times in body depth at dorsal-fin origin. Colouration: uniformly dark body without contrasting markings; and dark spots on dorsal and lateral surfaces of body (Ref. 128699).