The eastern Indian Ocean, including the Persian Gulf, is less intensively studied than other parts of the Indo-Pacific region with regard to its benthic fish fauna. This is particularly true in relation to gobies (family Gobiidae), which inhabit burrows in silty and muddy sediment or within coral and stones of rocky coasts.The burrowing goby Trypauchen vagina is characterized by an elongate reddish body that becomes purple in fixation, a continuous dorsal fin and anal fin that are connected to the caudal fin, small pelvic fins that are united and form a funnel-like disc, an oval pouch-like cavity at the dorsal margin of the operculum, canionoid teeth in jaws, and cycloid scales on the whole body except for the head. This goby inhabits shallow coastal waters