Erethistidae are a family of catfishes that originate from southern Asia. It includes about 45 species.
This family includes species previously placed in Sisoridae.[1] They were removed because they were thought to be more closely related to the neotropical Aspredinidae than to the remaining sisorids due to a number of morphological characters.[2] However, it has been suggested that the erethistid catfishes be included back into Sisoridae and some genera are included in that family by some authorities.[3]
Erethistids are found on the Indian subcontinent eastwards to western Thailand and northern Malay Peninsula.[4]
Many of the members of this family are small, cryptically colored fish with tuberculate skin.[4] Erethistids are distinguished from sisorids by having a pectoral girdle with a long coracoid process that extends well beyond the base of the pectoral fin; this structure can be felt through the skin in all genera and is visible externally in all genera except Pseudolaguvia. Erethistids differ from amblicipitids in that they lack a cuplike fold of skin in front of the pectoral fin (vs. possessing the cuplike fold) and have a dorsal fin with a strong spine and no thick covering of skin (vs. a weak spine with a thick covering of skin). Erethistids have nostrils close together, separated by a nasal barbel, which differs from akysids which have widely separated nostrils on each side of the head with a barbel on the posterior nostril.[5] Some erethistids possess a thoracic adhesive apparatus formed by longitudinal skin folds densely covered with unculi that appears to be an adaptation to life in fast-flowing waters; this closely resembles a similar structure in the sisorid Glyptothorax.[6]