Chaetodontidae: L III E8

Heniochus acuminatus Linnaeus, .1758.

Coachman

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
690-745	1	170	clear	narrow	stern	55% of NL	24

Egg: The oil globule is bright golden amber. The oil globule is relatively larger than LIIIE4 and LIIIE5, allowing early separation of this egg. The egg has a white appearance, due to white pigment in the developing embryo. Incubation is 24-28 hours. In one batch the yolk was noted to be segmented around the edge.

Larva: The 1-day larva has white pigment from behind the eyes, in a band over the yolksac to past the anus (B). In the 2-day larva, the white pigment has moved up over the notochord in a curious, chaotic pattern, interspersed with black spots, and a blush of red-brown over the notochord from oil globule to anus (C). The dorsal and ventral finfolds are peppered with fine black spots (C1). By day 4, the white pigment has formed two saddles over the notochord, with a longer black patch between (D). B: 1 day, C: 2 days, D: 4 days (26°C).

The fine black spots in the finfolds, and general appearance suggested this was a chaetodontid, and 2 sequenced larvae have matched 2 adult Heniochus acuminatus collected locally.

Linked samples	Offshore	Inshore
Eggs	201	22
Hits	5	6

This egg was uncommon off Park Rynie, but the catches indicate a summer spawner (blue graph). It was not seen in the DHM samples. Park Rynie linked samples had most of these eggs offshore, but biased by two big catches, of 43 (December 1997) and 150 eggs(December 2002), which render the data unreliable. While diving in the area, this species is generally seen inside the 30m contour. See Section 7.3 and Table 1 of the Introductory Notes, for more information on the linked samples.