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Cimbebasia 11 : 55-57,1989 55 Zoogeographical relationships of southern African harvestmen (Opiliones)- a preliminary account Wojciech Starega Natal Museum, Private Bag 9070, Pietermaritzburg 3200, RSA A preliminary analysis of the zoogeographical relationships of southern African harvest- men is given. The largest part of this fauna (63,6 %) is of Gondwanan origin. Other groups represented belong to the Palaeotropical(19,8 %) and Mediterrano-Afrotropical element (l6,6 7'0). It is an onerous task to try an analysis of the re- ies occur on the islands of the Indian Ocean lationships of the African harvestmen fauna. only: Gagrellidae (one species - probably in- One must remember, that from this continent troduced), Podoctidae (14) and Zalmoxidae (excluding the Mediterranean Region) 709 (five). nominal species have been described (Starega 1990), only few of which have been recently re- In southern Africa or in the region south of the vised. For over half of this number not only the Kunene and Zambezi rivers only eight from the generic placement but even the family affili- above-mentioned families occur, represented ation is obscure and badly in need of revision. by 217 nominal species. Four of these - "As- A quick and thorough revision of many Afri- samiidae", Biantidae, Phalangiidae, Samoidae - can groups is difficult as nearly all families are are also distributed in other parts of Africa. not confined to Africa and new, reliable criteria The remaining four - Caddidae, Neopilioni- for distinguishing families and genera have still dae, Pettalidae, Triaenonychidae - are confined to be established in many cases. to this region. It is therefore often more convenient and safer The most important component of the South to speak about family-complexes rather than African fauna is the family Triaen~n~chidae families. A classical case for such a family- -its 125 South African species constitute over a complex is the Assamiidae. The 291 nominal half (57,1%) of the total South African opilio- species known from Africa (and a similar num- nid species recorded so far and are limited to ber from South-East Asia and North Australia) the region south of the Limpopo and lower belong, in fact, to two or three different famil- Orange rivers. Further species occur in Mada- ies, not corresponding with their present div- gascar, Australia, Tasmania, Auckland and ision into 18 subfamilies. Crozet Islands, New Zealand, New Caledonia, Chile, Argentina and Uruguay. North The next good example is the Phalangodidae. American and East Asian (Japan, Korea) forms The family was supposed to be very large (sev- assigned to this family (Briggs 1971, Suzuki eral hundred species) and to have a nearly 1975, 1976, Shear 1977), but different in many global distribution, but in fact it is limited to aspects, belong elsewhere (possibly to the Par- Holarctic genera (Martens 1986). All the anonychidae). There are no common genera others, including the 43 African species, must between South Africa and other parts of the be reclassified into nobody knows how many family range, as the South African species de- families - there are no less than 12 family- scribed in Malagassy genus Acumontia Loman group names already available. were reclassified (by myself) and the South American species assigned to South African ge- The other larger African families: Triaenony- nus Ceratomontia Roewer (Ringuelet 1959) chidae (159 species), Biantidae (81) and Pha- may as well belong elsewhere. The subdivision langiidae (84) are either better defined or of this family is an open problem, but from the already partly revised (the latter, Staryga 1984). most widely accepted three subfamilies the The rest of the Afrotropical fauna belongs to Adaeinae are endemic in South Africa, Triae- seven small families: Caddidae (four species), nonychinae occur in the whole range of the Erecananidae (nine), Neogoveidae (two), Neo- family and the Triaenobuninae are characteris- pilionidae (two), Ogoveidae (two), Pettalidae tic for Australia and New Zealand with two (eight) and Samoidae (five); three further famil- doubtful representatives in Madagascar. 56 Cimbebasia 11,1989 If the North American and East Asian forms the continent. This is certainly the case with the were removed we would have a typical Gond- better known Biantidae and Phalangiidae, thus wanan group., Its suggested age being sup- building a link joining the fauna of the whole ported by some important plesiomorphic mor- Afrotropical Region. phological traits, e.g. penis with a big muscle, not hydraulic as in most other families of the The history of the colonisation of South Africa suborder Laniatores. by the members of these families must have been different but they have probably used the To the same Gondwanan element belong also same route along the eastern coast and the Dra- other South African families: the Neopilioni- kensberg Mountains. The Phalangiidae are rep- dae and Pettalidae and possibly the Caddidae. resented here by two genera: Guruia Loman The Neopilionidae have two monotypic genera and Rhampsinitus Simon, belonging to sub- restricted to the Cape Peninsula as well as gen- family Phalangiinae (sensu Starega 1976) of ap- era in Australia, New Zealand and South parently Mediterranean origin. both genera are America (Chile and Patagonia). They were endemic in Africa, but whilst the southern limit classified into three or four subfamilies and of the most widely distributed species of Gu- badly need a thorough revision, as the previous ruia, G. africana (Karsch), is Tongaland, the results obtained by Silhavf (1970) did not solve High Drakensberg and the Witwatersrand, the some crucial problems. numerous species of Rhampsinitus are distrib- The Pettalyidae have three genera with eight uted throughout southern Africa. Both genera species scattered from the Cape Peninsula connect the southern African fauna directly along the southern and eastern mountains up to with that of the eastern African mountains and northern Transvaal. Further genera occur in indirectly - on the subfamily level - with the Ceylon (one), Australia and New Zealand Mediterranean. (two) and Chile (one) (Shear 1980). Most species have been described from New Zealand The Biantidae-Biantinae have two small en- (Forster 1948, 1952) but a preliminary revision demic genera in South Africa: Biantessus of South African material has revealed that the Roewer in Natal and Cryptobiantes Kauri in group is far richer here than was previously eastern Transvaal but the bulk of their species suspected. I have found four additional species belongs to Metabiantes Roewer, widely dis- in Natal and two in the eastern Cape Province. tributed in Africa, from the Ivory Coast, Cam- eroon, Zaire and Kenya to the Outeniqua The single South African genus of the Caddi- Mountains in the Cape Province. dae-Acropsopilioninae, Caddella Hirst, with four species in the southern Cape Province and The "Assamiidae", with two species in South Natal, shows, according to Shear (1975), affini- Africa, three in Namibia, two in Zimbabwe ties with the Australian Austropsopilio Forster and twelve in Mozambique and the Samoidae, and the widely distributed but locally restricted with a single species in Mozambique, like the Anopsopzlio Silvestri (New Zealand, Chile, Biantinae, connect the southern African fauna Mexico, eastern and central parts of USA and with that of tropical Africa and the tropics of Canada, Japan). I am not completely con- the Oriental Region. The relations here are, vinced, however, with Shear's opinion about however, obscure due to the uncertain position this latter genus and tend to believe that there of all African forms. are different, similar but not closely related To sum up, the largest part of the southern taxa in the southern and northern parts of the African harvestmen fauna shows clear re- world. If my judgement proves to be right, we lationships with the faunas of other remnants might have here another group of Gondwanan of the former Gondwana. The four Gondwa- origin. nan families (Triaenonychidae, Pettalidae, All four families can be regarded as native el- Caddidae and Neopilionidae) contribute ements of the South African fauna. Together 63,6 % of the known fauna (139 species). The they constitute its major and most important Palaeotropical and Mediterrano-Afrotropical part. The other southern African families, such groups are far less numerous; the former (Bian- as Biantidae, Phalangiidae, "Assamiidae" and tidae, "Assamiidae", Samoidae) contributing Samoidae are relatively fresh intruders from the only 19,8 % (43 species) and the latter (Pha- north and most of their genera occur not only langiidae) only 16,6 % (36 species). This assem- in southern Africa but also in other regions of blage of elements of different origin is unique. Staryga- southern African Opiliones 57 REFERENCES SHEAR, W.A. 1980. A Review of the Cyphophthalmi of the United States and Mexico, w~tha Proposed Reclassifi- BRIGGS, T.S. 1971. The Harvestmen of Family Triaenony- cation of the Suborder (Arachnida, Opiliones). American chidae in North America (Opiliones). Occasional Papers of Museum Novitates 2705: 34 pp. the California Academy of Sciences 90: 43 pp. SILHAVY, V. 1970. Nouvelles recherches sur la famille des FORSTER, R.R. 1948. The Sub-order Cyphophthalmi Neopilionidae Lawrence. Bulletin du Museum National Simon in New Zealand. Dominion Museum Records in d8HistoireNaturelle, (2), 41, Suppl. 1: 171-1 75. Entomology 1: 8G119. STAR-FGA, W. ,1976. Opiliones - Kosarze (Arachno~dea). FORSTER, R.R. 1952. Supplement to the Sub-order Fauna Poloniae 5: 197pp. Cyphophthalmi. Dominion Museum Records in Ento- mology I: 179-211. STARFGA, W. 1984. Revision der Phalangiidae (Opi- liones), 111. Die afrikanischen Gattungen der Phalangiinae, MARTENS, J. 1986. Die Grossgliederung der Opiliones nebst Katalog aller afrikanischen Arten der Familie. Annales und die Evolution der Ordnung (Arachnida). In: BAR- Zoologici 38: 1-79. RIENTOS J.A. (ed) Actas X Congreso International de Aracnologia, Jaca 1 : 289-310. STARFGA, W. 1990. An annotated check-list of harvest- RINGUELET, R.A. 1959. Los aracnidos argentinos del men, excluding Phalangiidae, of the Afrotropical Region (Opiliones).