Fistulariidae: H I A3

Fistularia petimba Lacepede, 1803 and F. commersonii Ruppell, 1838

Serrate flutemouth and smooth flutemouth

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

1530-2060

0

n/a

clear

narrow

n/a

73% of NL

75+

Egg: When fresh this egg appears as a glass ball. The advanced larva develops metallic green and pink flecks (platelets) along the notochord (A). At this stage fine black dots can be seen all over the egg, if viewed on a white background. Incubation time is about 5 days (25°C); 7 days for one big egg.

Larva: The newly hatched larva initially looks like a clupeoid, but within a few days, small backward curved spines form in 4 rows down the length of the larva (C & D), and the snout elongates. The larva is then unmistakable. B: NH, C: 7 days, D: 8 days (25°C).

The big size range in this egg may be due to both locally known species spawning in the area. An effort will be made to barcode larvae hatched form the upper and lower egg size ranges. Nine larval DNA barcode sequences are currently available, one of which matches the sequence of 1 locally collected adult F. petimba (BOLD).The other 8, all match the single F. commersonii adult barcode in my dendrogram.

At Park Rynie, the egg was collected over the warmer months of October to March (blue graph). It was seen three times in the DHM samples, singly each time (green graph). In the Park Rynie linked samples, they were more common offshore (73%), but the percentage is the same askob, the inner of the two indicator species. This puts spawning at about the same distance offshore as Aliwal Shoal, which probably holds the biggest population of these two species in the area. See Section 7.3 and Table 1 of the Introductory Notes, for more information on the linked samples.

Linked samples

Offshore

Inshore

 Eggs

143

54

Hits

61

44