Taxonomy and distribution of ariid catfishes from the arabian gulf

Four morphologically distinct species of ariid catfish are found in northern regions of the Arabian Gulf, Arius thalassinus, A. dussumieri, A. tenuispinis and A. bilineatus, the latter having been frequently confused with and reported as A. thalassinus in earlier studies. An index of simple observations and measurements based on tooth patch structure and body dimensions was devised to distinguish between the four species. The recognition of A. tenuispinis and A. dussumieri in the Arabian Gulf greatly extends their reported distribution ranges.