Lampriformes: Trachipteridae: H I A2
Zu cristatus (Bonelli, 1820)
Scalloped 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 |
2065-2330 |
0 |
n/a |
clear |
narrow |
n/a |
53% of NL |
Ca 80 |
Egg: This egg has only been seen on four occasions in 25 years. The newly collected egg is illustrated in Plate A (arrowed, alongside a further advanced, spiky egg of CHIA1). No pigment was noted on the tiny embryo within the egg, but there were scattered black pigment spots on the yolk surface 4 days later, more dense near the embryo (A1). Incubation is at least 10 days (23°C).
Larva description: The newly hatched larva has unpigmented eyes, with long dorsal and pelvic fin elements (B). Myomere split was 24 + 56. A1: 4 days PC, B: NH, D 13 days PC, 2 days post hatch (23°C).
The most recent egg, collected in July 2008, had a lower myomere count of 65 (see box data above), and the hatched larva (Plate D) has been barcoded, matching Zu cristatus from New Zealand (DSLAR565-09 in BOLD). This suggests there might be at least two species in this egg catagory, and that the larva in Plate B is not Zu. Two of the 4 eggs were collected in November, 1 in February and 1 in July.