Soleidae: M III A5
Pagusa nasuta (Pallas 1814). Synonyms: Solea turbynei Gilchrist, 1904; S. bleekeri (Boulenger, 1898)
Blackhand sole
|
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 |
|
750-800 |
multiple |
NA |
clear |
narrow |
astern |
40% of NL |
ca 35 |
.
Egg: This unmistakable egg always has a light honey coloured hue throughout (A), and the light amber oil globules resemble a bunch of grapes. The embryo is densely covered in yellow pigment, which, on the yolk, is concentrated on the perimeter away from the embryo (A). The eggs usually hatch in the bucket or bowl, during evening processing, indicating an incubation period of about 24 hours.
Larva: The NH larva is compact, with the oil globules concentrated astern (B). The small size, and pigment pattern, made the early larvae easy to identify (C, D & E). B: NH (ventral view), C: 2 days, D: 4 days, E: 8 days, F: 12 days, G: 18 days (24°C).
The larva proved easy to rear, despite only small numbers of eggs being obtained at any one time. Three larvae from eggs have been barcoded, and match 5 locally collected adults (BOLD).
These amazingly precocious larvae were settling on the bottom of the rearing tank at about day 12 (F), when flexion was also complete. Note that the left eye has not completed its journey to the right side (F). This is also the size and stage seen recruiting into the Lovu and Mkomazi estuaries. In a batch of 57 juveniles collected recruiting into the Mkomazi estuary on 19 October 2005, mean SL was 3.5mm (preserved) and all had the left eye in transit.
| Linked Samples | Offshore | Inshore |
| Eggs | 21 | 53 |
| Hits | 4 | 16 |
This species spawns all year round, with a peak in winter (blue graph). Annual egg numbers have dropped since 1988, when exceptional numbers were collected. The egg was only seen twice in the DHM samples, in May and November. It has also been recorded from St Lucia estuary (Connell 1996). In the Park Rynie linked samples, the egg was more frequently seen in the inshore samples (72%), indicating spawning shoreward of the 20m depth contour. See Section 7.3 and Table 1 of the Introductory Notes, for more information on the linked samples.