Genus: Opisthonema, Thread herring, Thread-Herrings

top jaw - no central notch
D last ray = long filament

rear of gill opening - 2 fleshy lobes
pelvic I, 7
full row belly scutes
OPISTHONEMA
THREAD-HERRINGS
Body deep, compressed; mouth short, opens at front, oblique, without a front notch between top jaws; top jaw of 2 toothed bones; teeth small, conical; rear of gill opening on body with 2 fleshy lobes; dorsal at about midpoint of body, last ray long and filamentous; anal fin with base shorter than head, origin well behind dorsal fin; pelvic fins on the abdomen, insert under center of dorsal fin base, i, 7; a forked tail fin; belly with keel of scutes before and behind pelvics, no W shaped scute before pelvics; scales relatively small (< 50 in lateral series), irregularly arranged.
A new world, tropical to subtropical genus of 5 species; one west Atlantic species in our area.