Mullidae: K III A10

Parupeneus fraserorum (Randall & King, 2009), but see note below on the lethrinid Gymnocranius griseus

Frasers' goatfish

 

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

745-890

1

155-190

clear

Narrow*

bow

31% of NL

24

 

Egg: The typical size of this egg is 790/170. Black dots appear on the embryo, in 2 rows dorsally (which merge midway down the embryo), and scattered on the yolk next to the embryo (A1). On the oil globule, they are ventral, and numerous (A1). *The PVS can be wider than usual in some batches of eggs. The oil globule is usually oblong, and always untinted. Incubation is about 35 hours.

Larva: This larva was separated from the previous one (KIIIA9), by the significantly shorter gut (C & D). At 4 days, the larva develops a dark line of pigment over the gut (E1). B: NH, C: 2 days, D: 4 days, E: 5 days (24°C).

Repeated attempts to rear this important egg, were unsuccessful. Seven larvae have been barcoded, all matching the sequence of a two adult P. fraserorum collected off the KZN coast. In a further development, 3 larvae from eggs collected on 28 November 2007, and labelled as KIIIA10 type2, have sequenced as Gymnocranius griseus (see also KIIIB3A). It will be necessary to try to separate these two species in future.

Ikeda & Mito (1988) illustrate Upeneus bensasi and Parupeneus chrysopleuron eggs as having a segmented yolk. Shao et. al. (2001) list U. bensasi, but do not mention a segmented yolk. This study has also indicated eggs of some mullids with the yolk segmented (EIIIB1), and others clear.

This was the 11th most common egg off Park Rynie (Introductory Notes; Table 3). It occurs all year round, with a slight spring maximum (blue graph). It was also seen in the DHM samples, with a similar scattered presence through the year. At Park Rynie, the egg has shown a steady presence, after being virtually absent in the first year (white graph). In the Park Rynie linked samples, the eggs were slightly more abundant offshore (57%), but this low ratio indicates another species that is spawning on the shelf, inside the spawning zone of the two indicator species, in 20-30m water depth. See Section 7.3 and Table 1 of the Introductory Notes, for more information on the linked samples.

Linked samples

Offshore

Inshore

 Eggs

5945

4424

Hits

242

214