Biology of Finfish and Shellfish (2+1)

Sphyraenidae

• Larvae are elongate , are moderately compressed initially ,but become approximately round in cross –section, and have 24 myomeres (13-17+7-11).
• The gut is straight and long, extending to 60-80%BL. A prominent gas bladder is located above the anterior portion of the gut in preflexion larvae, but it moves posteriorly with increasing larval size.
• The horizontal mouth is large but barely reaches the anterior edge of eye.
• Small teeth are present in both jaws by 3.5mm. the round eye is large relatives to BL, but small to moderate relative to the large head.
• The spines of both dorsal dins and the anal din begin to form at about 8mm and incipient rays of the pectoral fins are present at this time.
• The pelvic fin is located posterior to the pectoral-fin base near the level of the spiny dorsal fin. By 16mm, full fin complements are present in all fins.
• At 16mm, the yound barracuda resembles a miniature adult except for the lack of scales which begin to form at about 23min.
• Barracuda larvae are moderately to heavily pigmented. Characteristic pigment includes; melanophores ventrally on the tail that continue over the gut; pigment below the brain and on to the snout giving the impression of a line through the eye; and relatively heavy dorsal pigment on trunk and tail that varies with species from large, stellate, biserial melanophores to small, uniformly scattered melanophores that can extend laterally to the midline.
• Pigment may be present on the head, ventrum of the gut, and laterally on the tail.