In the hill-stream fish, Pseudoecheneis sulcatus the adhesive organ is located on the ventral surface of thorax behind mouth, between opercular region and bases of pectoral fins. It is broader anteriorly end slightly narrower posteriorly, comprising a distinct arrangement of transverse ridge and grooves alternating with each other. Morphological ridges further display the wavy surface pattern with subridges and subgrooves. The subridges bear a number of long, hooked or curved or blunt headed, epidermal spines. By attaching to the organic growth on the rocky substrata of river bed in a collective fashion, spines are responsible for the effective adhesion on substrata, thus, avoid the washing away of fish by violently fast flowing water current. Glandular secretion minimises the mechanical abrasion of spines.