Sciaenidae: L III A4

Umbrina canariensis Valenciennes, 1843. (? and others)

Baardman

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
910-1010	1	220-240	clear	narrow	stern	41% of NL	25

Egg: Fresh eggs have a clear to light or dark amber oil globule. The neat appearance of black pigment dots, evenly distributed on the embryo, and ventrally on the oil globule, are fairly reliable characters to identify the later egg (A & A1). Just prior to hatching the embryo can be distinctly brown, as more yellow pigment spots appear among the black along the notochord. Incubation is about 35 hours.

Larva: The dense brown-black pigment surrounding the notochord from shoulder to midtail, additionally spotted with orange-yellow pigment (B & C), distinguishes this early larva from all others in the area, except LIIB6. At 3-5 days the dark pigment has re-arranged into the pattern shown in Plates D & E, with only an indistinct separation of pigment between trunk and midtail (compared to LIIB6). At 13 days the larva was still preflexion (E, 25°C), while at 19 days, flexion was virtually complete (G, 23°C). B: NH, C: 2 days, D: 3 days, E: 5 days, F: 13 days, G: 19 days, H: 30 days (24°C), I: 40 days (22°C). The Plate I juvenile has a dorsal fin count of IX/I,24 and anal fin II,7.

This larva proved quite easy to rear, and a growth series has been archived. I am, however, not convinced that F,G,H and I above, are all the same species. DNA barcoding confirms that there may be two or three species here. Fourteen larvae have barcoded as the same species, and match 5 locally collected adult U. canariensis (BOLD). Two larvae have provided sequences suggesting two other species, neither of which match either of our two Umbrina species, nor do they match sequences of adult Atrobucca nibe, Johnius dussumieri, J. fuscolineatus, and Otolithes ruber, which are available from locally collected fishes. Their close association with U. canariensis in my dendrogram suggest they may be other species of Umbrina.

Linked samples	Offshore	Inshore
Eggs	425	135
Hits	126	57

This was a fairly common egg off Park Rynie, seen all year round, though peaking in winter and spring (blue graph). It was only seen once in the DHM samples, in August. The catch at Park Rynie, through the 25 years of sampling, has shown a steady state, at a reduced level, after 5 years of higher abundance from 1988-1992 (white graph). It may be that this species benefited from the muddier offshore conditions following the 1984 cyclones and September 1987 floods, and became temporarily more abundant. It is not targeted by fishermen in the area, but does turn up in skiboat catches. The Park Rynie linked samples showed more of these eggs offshore (76%), suggesting spawning just offshore of the spawning aggregations of Argyrosomus japonicus (LIIIA8). See Section 7.3 and Table 1 of the Introductory Notes, for more information on the linked samples.