Hypoatherina tropicalis (Whitley, 1948)
Whitley's silverside
photo by Randall, J.E.

Family:  Atherinidae (Silversides), subfamily: Atherinomorinae
Max. size:  12.5 cm TL (male/unsexed)
Environment:  pelagic-neritic; marine; depth range - 0 m
Distribution:  Western Pacific: New Guinea, northern and eastern Australia, Madang, Maron and Bougainville Islands. Possibly present over a wide range in Melanesian waters. Aso found around Lord Howe Island.
Diagnosis:  Dorsal spines (total): 6-9; Dorsal soft rays (total): 8-11; Anal spines: 1-1; Anal soft rays: 11-14. Lips absent. Ascending process of premaxilla, short and broad. Gill rakers in first lower gill arch 18-22. Midlateral scales 39-46. Predorsal scales 17-22. Description: Characterized by translucent color; silvery blue sheen and silvery midlateral stripe; body depth 5.8-6.0 in SL; large eye, about 2.8 in head length; upper jaw extending vertical at front of eye; moderately long and narrow ascending process and two short and wide lateral processes in premaxilla; ramus of dentary highly elevated posteriorly; jaws, palatines, vomer and meopterygoids with small teeth (Ref. 90102).
Biology:  Inhabits waters close inshore. Often seen to jump out of the water, especially after sunset when they appear as fluorescent streaks. At night they appear to aggregate with Atherinomorus capricornensis around One Tree Island (eastern Australia). Probably eaten by larger commercial species (Ref. 9760).
IUCN Red List Status: Not Evaluated (N.E.) Ref. (130435)
Threat to humans:  harmless


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