Abstract
The eggs, early larvae and juveniles of the sharpnose pufferfish Canthigaster valentini are described, based on material collected in Great Barrier Reef waters. Eggs were obtained in the field by divers and reared in the laboratory. The eggs are spherical, strongly adhesive, 0.68-0.72mm in diameter, possess a dense cluster of small oil droplets, and hatch around sunset 3 to 5 days after fertilization. Newly hatched larvae have a small yolk sac, pectoral fin folds, 17 myomeres (6 pre-anal, 11 post-anal) and measure 1.30-1.40mm in notochord (standard) length. The eggs of C. valentini differ from those of other tetraodontids in being much smaller and having a longer incubation time. The larvae can be distinguished from other tetraodontid larvae by pigmentation, myomere count and size at hatching. Growth is most rapid during the first day of larval life. Age determinations (based on otolith microstructure) of field collected juveniles, both pelagic and newly settled, indicate a pelagic phase of between 64 and 113 days for this species. This estimate appears consistent with the extended pelagic juvenile stages observed in other tetraodontiform fishes and could indicate that C. valentini can delay settlement for some time after becoming competent to settle at a minimum age of 64 days.
