Pinguipedidae : L III E1

Parapercis robinsoni Fowler, 1929), among others.

Smallscale sandsmelt



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








32% of NL

ca 32


Egg: Yellow pigment is distributed in 7 patches on the embryo and all over the oil globule. Black pigment is dorsal on the embryo and ventral on the oil globule. Incubation is about 24 hours, and some eggs are seen fresh, implying both morning and evening spawning.

Larva: The NH larva has a combination of a patch of yellow in the dorsal finfold at mid-trunk (B, dorsal white arrow), and the last tail-blotch also creeping into the finfold, both dorsally and ventrally (B). Plate B1 shows myomeres and slight serration of the dorsal and ventral finfold edges on the taper towards the caudal finfold. Yellow pigment expansion into the finfolds continues, giving the 3-day larva a distinctive X-shape in the mid-tail (C & D). By day 5 the yellow pattern is beginning to shrink, although at 13 days the mid-tail patch was still present (F). Flexion was just beginning in the 20-day larva (G), but was complete by 35 days (H).  B: NH, B1: 1 day, C: 2 day, D: 3 days, E: 4 days, F: 13 days, G: 20 days, H: 35 days, I: 48 days, but described in my notes, as a runt (23-24°C), J: 47 days (22-23°C).

This larva was not too difficult to rear, although it was not tried often, after early success. Quite extensive collecting and SCUBA-diving in the area has only yielded three species, of which robinsoni is by far the most common. Both the juveniles shown in Plates I & J have 22 dorsal rays and 18 anal rays, matching robinsoni, whereas punctulata has 21 dorsal, and 17 anal rays (Heemstra, 1986a).  This count does however, also match P. schauinslandi, which has been seen at Park Rynie, and it seems likely that the pink specimen in Plate J is this species. It is curious that, despite this being a common species off Park Rynie, no larvae have been successfully barcoded, and not for want of trying. Even the adults have proved difficult to barcode. Despite subitting tissue from 7 P. robinsoni adults, none were successfully barcoded. The same applies to this egg, with at least 15 failures. Use of alternative primers in the analysis is indicated.


Linked samples Offshore Inshore
Eggs 551 998
Hits 111 177

P. robinsoni eggs made the top 50 most common at Park Rynie, and the top 25 in the DHM samples (Introductory Notes; Tables 3 & 2 respectively). They showed a spring spawning peak off Park Rynie, but the eggs were present in all but the hottest months (blue graph) The DHM samples (green graph), showed less pattern. Comparison of eggs collected per year off Park Rynie, shows a slight increase after the first 5 years (white graph). The Park Rynie linked samples had more eggs inshore (64%), indicating spawning occurs mostly in shallow (<20m) water. See Section 7.3 and Table 1 of the Introductory Notes, for more information on the linked samples.