Scombridae: L II A4

Unknown

Egg diameter in µm	Number of oil globules	Diameter of oil globule in µm	Yolk texture	Perivitelline space	Position of oil globule at hatch	Gut length   at eye- pigment stage	Myomeres
1295-1320	1	230-325	clear	narrow	stern	42% of NL	ca37

Egg: The developing embryo is peppered with black and greenish-yellow stellate pigment spots, which also appear on the yolk and oil globule. The oil globule is light amber. Incubation is 45-50 hours.

Larva: The early larva (B) has a woolly edge of white/yellow pigment to both the dorsal and ventral finfolds, but note that this larva is distorted, and the oil globule is misplaced. Finfold pigment has almost disappeared by day 4 (C), and the pectorals are enlarged. But for the myomere count, one might mistake this for a scorpaenid. At 20 days, the juvenile was postflexion, with a V-shaped caudal fin (D), and strong preopercular spines (D1: black arrows). C: 4 days, D: 20 days (25°C).

This egg has only been seen off Park Rynie on 4 occasions (blue graph). The larva is clearly a thunnid (Tribe Thunnini; Richards, 2006), of which Euthynnus affinis, Katsuwonus pelamis and Thunnus albacares are the most frequently seen off Park Rynie. K. pelamis has been linked to another egg off Park Rynie (LIIIA11), while the egg of T. albacares is smaller, measuring 0.9-1.04mm (Richards 2006, from Mori et al 1971). Two larvae from eggs thought to have been this species, have matched Seriola lalandi (E II A2), suggesting this egg is sometimes mis-identified.