Sphyraenidae: E III A2A

Sphyraena sp.

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
940-1010	1	240-265	segmented	narrow	bow	64% of NL	25

Egg: When seen at the stage photographed (A), the distinguishing feature of this egg is the ring of yellow pigment around the oil globule. On a white background, black pigment dots will be seen ventrally on the oil globule. The embryo has yellow behind each eye, and two rows of yellow pigment down the length of the body. The oil globule is clear. Incubation is 30-35 hours.

Larva: The 1-day larva has a distinctive yellow pigment pattern (B). By day 4, the yellow pigment is fading, and the body is elongating (C). At day 5, black pigment has become prominent both dorsally and ventrally along the notochord, interspersed with yellow (D & E).  B & B1: 1 day, C: 4 days, D & E: 5 days (23°C).

Originally I assumed this was a carangid, based on the pigment of the early larva. The elongate larva at 4-5days is, however, unlike most carangids. Four larvae of this species have been DNA barcoded, but a match has not yet been found among the 4 Sphyraena species for which adult barcodes are currently available (S. acutipinnis, S. barracuda, S. chrysotaenia and S. jello). When plotted in a dendrogram, it came out closest to Sphyraena chrysotaenia (though not a match, BOLD reference). Shao et al (2001) illustrate a sphyraenid egg (pg 141) which is similar in appearance, though smaller at 780µm (but note that use of circular lighting has created a ring around the oil globule in their photograph). Their yolksac larva is also similar, with a very similar yellow pigment pattern.

This egg is rare at Park Rynie, having been seen only 3 times, twice in November and once in May. Thus no graphics are presented. On each occasion there were three eggs in the sample. Six of the 9 eggs were in inshore samples.