Emmelichthyidae: F II A8

Plagiogeneion rubiginosum (Hutton, 1875)

Rubyfish.

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
1030-1225	1	240-275	segmented	narrow	stern	53% of NL	24-25

Egg: The oil globule is bright amber to yellow-amber(A & B), and the yolk is misty, with a granular surface. Segmentation is sometimes difficult to confirm, and can be confined to the edge of the yolk. Yellow and black pigment spots develop all over the larva. There are a few yellow pigment spots dorsally on the oil globule, and black spots ventrally. Incubation is about 45 hours (23°C).

Larva: The newly hatched larva has black pigment dots scattered on the notochord, especially over the gut (C), and a dense line  along the ventral edge.  This rapidly coalesces to form the dense line along the notochord, that is characteristic of this species (D, E & F). C: 1 day, D: 2 days, E: 4 days, F: 6 days (22-23°C).

Rearing attempts were always hampered by small numbers of eggs, and none were successful. Three htched larvae have been barcoded, and match a single adult collected on the Agulhas Bank (BOLD). Confirmation awaits further adult and larval sequences.

Linked samples	Offshore	Inshore
Eggs	49	4
Hits	16	3

This species is a winter/spring spawner (blue graph). The pattern of egg collection at Park Rynie over the years (white graph), shows an increase in eggs from 1989 to 1991, but the data is rather thin. The Park Rynie linked samples had 92% of these eggs in the offshore samples, suggesting spawning outside the 50m contour, consistent with this deepwater species. See Section 7.3 and Table 1 of the Introductory Notes, for more information on the linked samples.