| Low total vertebrae count (27-31); uniquely low pelvic fin ray count (6); slender body; gut short, larger anterior section tapers gradually, slight sigmoid curvature; head moderate in size, initially somewhat rounded; snout becomes somewhat elongate and blunt at tip; eyes narrow, becoming irregularly oval; a crescent of choroid-like tissue on dorsal surface of eye by 4.0 mm and on ventral surface by about 6.0 mm; teeth minute; pigment sparse but diagnostic, particularly the mid-hypural streak; the pineal organ in the interorbital region is visible in late postflexion larvae; transforms at small size; Dn, Br2, PVO1, PVO2, VLO, and PO1-5 photophores form first; Br2 form in adult position below eye.
Pigmentation:
Preflexion: by about 2.8 mm, 1 laterally on midgut just anterior to preanal arch of gut; by about 3.2 mm, 1-4 (usually 1) ventral midline postanal dashes; by about 3.8 mm, 1 above developing gas bladder and pair on terminal gut section.
Flexion: usually 2 or 3 on lateral gut; by about 5.0 mm, 1 or a streak at mid-hypural margin.
Postflexion: 2-7 (usually 3 or 4) in postanal ventral midline series, displaced to either side of anal fin base; up to 3 laterally on gut in largest larvae.
Transformation: blotch laterally on gut.
Sequence of fin development: caudal, dorsal and anal and pectorals, pelvics. |