Caligid fish parasites from the South and East coast of South Africa

[摘要] English: Caligus Muller, 1785 are caligid copepods found almost exclusively on marine fishhosts. This genus is represented by more than 200 species in the oceans of the worldand is the largest genus of parasitic copepods. A total of 39 species of Caligusparasites have been recorded off the coast of Africa, and 26 species are found alongthe South African coastline. Surveys carried out from 1992 to 1998 in Lake St Luciaand from 1997 to 1999 at De Hoop Nature Reserve and Jeffreys Bay along the coastof South Africa, revealed the presence of caligid copepods, of the genus CaligusMilIler, 1785, occurring on the body surfaces and gills of many estuarine andintertidal fish species. Four different species were collected from marine hostsnamely, Caligus acanthopagri Lin, Ho & Chen, 1994, Caligus confusus Pillai, 1961,Caligus engraulidis Barnard, 1948, and Caligus mortis Kensley, 1970. The first threespecies mentioned were collected in Lake St Lucia, KwaZulu-Natal, on the east coastof South Africa, and C. mortis were collected at De Hoop Nature Reserve and JeffreysBay on the south coast of South Africa. In the present study, males of C. engraulidisand C. mortis are described for the first time and is new to science. Further studiesrevealed that interesting hypersymbionts were found attached to the caligids.Sessiline ciliophorans were found on both C. acanthopagri and C. engraulidis andrepresents a first record for South Africa. Udonella caligorum Johnston, 1835 werefound on the caligid host C. engraulidis. This monogenean worm have a complicatedhistory, for it was placed in different taxa and families since it was first described in1835. Phylogenetic analysis as well as morphological analysis places this wormfirmly as a polyonchoinean monogenean alongside the Gyrodactylidae. Thesehypersymbionts do not feed on the copepods and have no detrimental effects on theirhosts.

[发布机构] University of the Free State