Sicyopus auxilimentus Watson & Kottelat 1994

Amphidromous. Refers to fishes that regularly migrate between freshwater and the sea (in both directions), but not for the purpose of breeding, as in anadromous and catadromous species. Sub-division of diadromous. Migrations should be cyclical and predictable and cover more than 100 km.Characteristic elements in amphidromy are: reproduction in fresh water, passage to sea by newly hatched larvae, a period of feeding and growing at sea usually a few months long, return to fresh water of well-grown juveniles, a further period of feeding and growing in fresh water, followed by reproduction there (Ref. 82692).

Found over coarse gravel in a small, rather swift, shallow stream about 3 m wide. Possibly amphidromous (Ref. 26364).

Sicyopus auxilimentus is a species of goby endemic to the Philippines where it is only known to occur in Lagu Lagu Creek on Leyte Island. This species can reach a length of 2.9 centimetres (1.1 in) SL.