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Reported Siphonostomatoid Copepods Parasitic on Marine Fishes of Southern Africa

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Reported Siphonostomatoid Copepods Parasitic on Marine Fishes of Southern Africa REPORTED SIPHONOSTOMATOID COPEPODS PARASITIC ON MARINE FISHES OF SOUTHERN AFRICA BY SUSAN M. DIPPENAAR1) School of Molecular and Life Sciences, University of Limpopo, Private Bag X1106, Sovenga 0727, South Africa ABSTRACT Worldwide there are more than 12000 species of copepods known, of which 4224 are symbiotic. Most of the symbiotic species belong to two orders, Poecilostomatoida (1771 species) and Siphonos- tomatoida (1840 species). The order Siphonostomatoida currently consists of 40 families that are mostly marine and infect invertebrates as well as vertebrates. In a report on the status of the marine biodiversity of South Africa, parasitic invertebrates were highlighted as taxa about which very little is known. A list was compiled of all the records of siphonostomatoids of marine fishes from southern African waters (from northern Angola along the Atlantic Ocean to northern Mozambique along the Indian Ocean, including the west coast of Madagascar and the Mozambique channel). Quite a few controversial reports exist that are discussed. The number of species recorded from southern African waters comprises a mere 9% of the known species. RÉSUMÉ Dans le monde, il y a plus de 12000 espèces de Copépodes connus, dont 4224 sont des symbiotes. La plupart de ces espèces symbiotes appartiennent à deux ordres, les Poecilostomatoida (1771 espèces) et les Siphonostomatoida (1840 espèces). L’ordre des Siphonostomatoida comprend actuellement 40 familles, qui sont pour la plupart marines, et qui infectent des invertébrés aussi bien que des vertébrés. Dans un rapport sur l’état de la biodiversité marine en Afrique du Sud, les invertébrés parasites ont été remarqués comme étant très peu connus. Une liste de tous les signalements des siphonostomatoïdes des poissons marins des eaux sud-africaines (du nord de l’Angola le long de l’Océan Atlantique au nord du Mozambique le long de l’Océan Indien, incluant la côte occidentale de Madagascar et le Canal de Mozambique) a été établie. Quelques rapports très controversés sur le sujet sont aussi discutés. Le nombre d’espèces reconnues en Afrique du Sud ne comprend guère plus de 9% des espèces actuellement connues. 1) e-mail: [email protected] © Koninklijke Brill NV, Leiden, 2005 Crustaceana 77 (11): 1281-1328 Also available online: www.brill.nl 1282 SUSAN M. DIPPENAAR INTRODUCTION Currently there are more than 12000 species of copepods known worldwide. Of these, about 4224 are symbiotic (parasitic or commensalistic) and mostly dis- tributed over six orders (Calanoida, Harpacticoida, Monstrilloida, Cyclopoida, Poecilostomatoida, and Siphonostomatoida). However, the majority of symbiotic species belong to the last two orders, with 1771 known poecilostomatoids and 1840 known siphonostomatoids. Symbiotic copepods infect most of the animal groups including Porifera, Cnidaria, Platyhelminthes, Nemertea, Sipunculida, Echiura, Annelida, Mollusca, Arthropoda, Phoronida, Brachiopoda, Echinodermata, Hemi- chordata, Urochordata, and Vertebrata (Chondrichthyes, Osteichthyes, and Mam- malia) (Huys & Boxshall, 1991; Ho, 2001). The order Siphonostomatoida cur- rently consists of 40 families (Martin & Davis, 2001), parasitic on both vertebrates and invertebrates and these are mostly marine with only two families with fresh- water representatives (Benz, 1994). Reports on the status of marine biodiversity in South Africa stated that very little, if anything, is known about some marine taxa, e.g., parasitic invertebrates (Gibbons, 1999, 2000). In an attempt to determine how many siphonostomatoid parasites of marine fishes captured off southern Africa are known, a detailed literature search was done to compile a list of the marine copepods, their fish hosts, and localities reported from southern African waters. METHODS The list was compiled of all published reports south of 6◦00S (northern border of Angola) along the west coast of southern Africa (Atlantic Ocean) and south of 10◦30S (northern border of Mozambique) along the east coast (Indian Ocean) including the west coast of Madagascar and the Mozambique Channel. To avoid duplication, some reports by T. R. R. Stebbing and others were dis- carded, as K. H. Barnard again reported these from museum material during the 1940s and 1950s. Furthermore, reports by W. H. Oldewage in specific pub- lications and mentioned again in the checklist of the piscine parasitic Copepoda of Africa (Oldewage & Avenant-Oldewage, 1993) were only listed once. Names of copepods, hosts, and authors reported were verified and changed to latest accepted as far as possible. Copepod names were verified using different publications as well as personal communication with Dr J.-S. Ho. Host names were verified with the aid of Smith & Heemstra (1988), FishBase: http://www.fishbase. org/search.html, California Academy of Sciences Catalog of Fishes: http://www. calacademy.org/research/ichthyology/catalog/fishcatmain.asp and personal com- munication with Mr Ofer Gon..
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