New morphological information on the parasitic copepods Caligus epinepheli Yamaguti, 1936 and Caligus rotundigenitalis Yu, 1933 (Copepoda, Caligidae) from South Africa

摘要

Caligus epinepheli were collected from De Hoop Nature Reserve along the south coast and from Lake St Lucia along the east coast of South Africa. Caligus rotundigenitalis were collected from Lake St Lucia. Two females, one male, and one chalimus of C. epinepheli were removed from the gill chambers of Diplodus sargus capensis and Rhabdosargus holubi. Only two females of C. rotundigenitalis were removed from inside the operculum of Rhabdosargus holubi. Both species represent new host and distribution records for South Africa. The morphological features of these two species were studied with the aid of scanning electron microscopy. Numerous small setae were observed on the marginal membrane as well as on the dorsal shield of C. epinepheli, probably with a sensory function. Another interesting feature is the long seta near the base of the maxillule, bearing spinules on both margins. All other known Caligus species studied so far have a smooth, long basal seta of the maxillule. In C. rotundigenitalis, the first four spines on the second segment of the exopod of leg 4 are covered with spinules.