Lampridiformes: Trachipteridae: CD I A1

Trachipterus sp

Ribbonfish

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
2280-2920	0	N/A	segmented	narrow	N/A	50% of NL	ca90

Egg: This egg appears “pink and furry” (Plate A), and close examination indicates it has a fine carpet of hairs on the chorion. At a later stage it sometimes has big black pigment blotches visible through the fuzzy coating (B). As the embryo develops, the black pigmented expansions on the dorsal finfold thread can be seen through the chorion. The egg takes up to 10 days to hatch (24°C). Unfortunately in captive conditions the egg often fails to hatch.

Larva: At hatching the impressive larva has well developed eyes and a functional mouth(C). Myomeres are very fine and difficult to count in the larva, but appear to be about 90. Note the additional “finger” at the tip of each elongate pelvic fin ray, which has been seen in several specimens. C: NH (9 days PC).

This egg was uncommon, which is not surprising as trachipterids are members of the offshore epipelagic community (Heemstra and Kannemeyer 1986). The specimen in Plate C above, is assigned to Trachipterus, based on the myomere count, despite its close resemblance to Lophotus (Lophotidae), and the egg having a “furry” chorion, which Lophotus lacepede has (Olney, 2006). Olney and Richards (2006) show eggs of Trachipterus from the Gulf of Mexico, but do not mention a furry texture to the chorion. A single larva has been barcoded but no match is currently available in BOLD (see CDIA1A).

The few eggs collected, suggest it is a winter and spring spawner (blue graph), with 93% in offshore samples of the Park Rynie linked samples. See Section 7.3 and Table 1 of the Introductory Notes, for more information on the linked samples.

linked samples	Offshore	Inshore
Eggs	25	2
Hits	11	2