Clupeidae: G II A1
Hilsa kelee (Cuvier 1829)
Kelee shad
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 |
1080-1175 |
multiple |
90 |
segmented |
narrow |
central |
84% of NL |
42-43 |
Egg: The size, segmented yolk and multiple oil globules are unique in the local context. The egg is very buoyant, and if left in a bowl of seawater (35‰), will break the surface. Incubation time is about 28 hours (25°C).
Larva: The NH larva has virtually no pigment (B). Eyes and mouth are undeveloped, but by day 2 are fully formed. No photographic record is available for days 3-18. At 19 days black pigment is confined ventrally on the notochord, and the air bladder is formed, just anterior to midway between snout and anus (C: black arrow). Flexion is just starting. At 24 days, flexion is complete, and pigment has formed behind the otic capsule, forming a triangle of spots, with the other two on the nape and below the pectoral base (D, upper specimen). B: NH, C: 19 days, D: 24 days (23°C).
Eight larvae, hatched from this egg, have been DNA barcoded, including 3 from Park Rynie, and match 4 adult H. kelee collected locally (BOLD).
Hilsa is a spring and summer spawner, better illustrated in the DHM samples (green graph), since it was quite rare at Park Rynie (blue graph). It was the second most common egg in the DHM samples (Introductory Notes: Table 2), though hugely distorted by a single sample of over 8000 eggs, without which it would have been the 9th most common. The annual catch of eggs off Park Rynie is unusual (white graph), since they were not collected until 1998, only appeared frequently in February/March 2004, and have not been seen again since March 2005. A net tow near Durban Harbour mouth in November 2009 yielded 670 H. kelee eggs, confirming their continued presence there. In the Park Rynie linked samples, they were marginally more common inshore (51%), indicating spawning around the 20m contour. See Section 7.3 and Table 1 of the Introductory Notes, for more information on the linked samples.
Linked samples |
Offshore |
Inshore |
Eggs |
26 |
27 |
Hits |
3 |
4 |