JANE' B. WALKER\ J.E. KEIRANS 2 and R.G. PEGRAM 3. Rhipicephalus aquatilis Walker, Keirans & Pegram, sp. nov.

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1 Onderstepoort Journal of Veterinary Research, 60: (1993) Rhipicephalus aquatilis sp. nov. (Acari: l.xodidae), a new tick species parasitic inly on the sitatunga, Tragelaphus spekei, in East an, d Central Africa JANE' B. WALKER\ J.E. KEIRANS 2 and R.G. PEGRAM 3 ABSTRACT WALKER, JANE B., KEIRANS, J.E. & PEGRAM, R.G Rhipicephalus aquatilis sp. nov. (Acari: Ixodidae), a new tick species parasitic ainly on the sitatunga, Tragelaphus spekei, in East and Central Africa. Onderstepoort Journal of Veterinary Research, 60: This tick, originally referred to as Rhipicephalus species Ill by Yeoan & Walker (1967), was first collected fro a sitatunga, Tragelaphus spekei, and then occasionally fro cattle, in Tanzania. Further collections, ostly fro sitatunga, have since been seen fro Uganda and Zabia. Descriptions of the adults of this species are given, together with inforation on their hosts and their distribution. INTRODUCTION In 1967, Yeoan & Walker designated five batches of adult ticks fro north-western Tanzania as Rhipicephalus species Ill. They had been unable to assign these ticks to any known species in this genus. Since then a further seven collections of this tick fro Uganda and three fro Zabia have been seen. The specific nae, aquatilis, a Latin ter eaning "living in or near water", refers to the fact that all the collections have been ade fro hosts in sei-aquatic habitats. The following are descriptions of the adults of this species. ' Onderstepoort Veterinary Institute, Onderstepoort, 0110 South Africa 2 3 Institute of Arthropodology and Parasitology, Georgia Southern University, Statesboro, Georgia , USA Present address: Food and Agriculture Organization Tick Control Project, Veterinary Research Laboratory, P.O. Box 8101, Causeway, Harare, Zibabwe Received 14 June1993-Editor DESCRIPTIONS Measureents of the ticks are given in illietres (). The range given represents the easureents of the largest and sallest speciens in a batch of ten ales and 14 feales collected fro a sitatunga, Lake Bangweulu, Zabia (RML ). Rhipicephalus aquatilis Walker, Keirans & Pegra, sp. nov. Synonys Rhipicephalus sp. Ill sensu Yeoan & Walker The ixodid ticks of Tanzania: 174. Rhipicephalus sp. Ill, in Keirans George Henry Falkiner Nuttall and the Nuttall tick catalogue (Nuttall Collection 1714): 736; (Nuttall Collection 3949): Rhipicephalus sp. Ill, in Pegra, Perry, Musisi & Mwanauo Experiental and Applied Acarology, 2:35, 42. Rhipicephalus sp. Ill, in Matthysse & Coiba The ixodid ticks of Uganda :

2 Rhipicephalus aquatilus sp. nov. (Acari: Ixodidae) HOLOTYPE. d', collected fro a sitatunga (Tragelaphus spekei) at Kaisho (01 19'S, 30 37'E), Karagwe District, Tanzania, on 14 August 1959 by Mrs G. Tullock, fro Tanzania Tick Collection WA/99, deposited in the Natural History Museu, London. ALLOTYPE., data as above. PARA TYPES. 4 d'd', 2, collection data as above, deposited in the Natural History Museu, London; 2 d'd', 2, collection data as above, deposited in the Onderstepoort Tick Collection, OP 3143 i; 2 d'd', 2, collected fro T. spekei, Uganda, OP 3143 ii; 1, collected fro bovine, Liulunga (15 09'S, 23 1 O'E), Zabia, on 31 March 1982, by R.G. Pegra, OP 3143 iii (TC 737); 1.collected fro bovine, Liulunga, Zabia, in April 1982, by R.G. Pegra, OP 3143 iv (TC 770); 10 d'd', 14.collected fro T. spekei at Lake Bangweulu (11 05'S, 29 45'E), Zabia, on 1 Septeber 1991, United States National Tick Collection, RML MALE (Fig. 1, 3-5) CAPITULUM (Fig. 3). Approxiately as broad as long, the length (including cornua) x breadth varying fro 0,85 x 0,66 to 0,82 x 0,66. BASIS CAPITULI. Length fro palpal insertion to cornua apices varying fro 0,48-0,38. Anterolateral argins straight, diverging posterolaterally; posterolateral argins straight to slightly concave, extending anteriorly over the apical processes of coxa I. Cornua large, broader than long, triangular. Dorsal setae of basis capituli as in Fig. 3. Basis capituli ventrally with all features of palps and hypostoe typical of the genus. PALPS (Fig. 3). Article I slightly elongate, easily visible dorsally; article II longer than article Ill; both broader than long. BODY (Fig. 1). lnornate, typical colouration dark reddish brown to alost black, including lateral idiosoal area and conscutu; leg colouration uniforly dark reddish brown. Length (fro scapular apices to posterior body argin) x breadth varying fro 3,32 x 2,21 to 2,57 x 1,71 ; broadest at level of anterior argin of spiracle, broadly rounded posteriorly. In engorged speciens the idiosoal wall bulges slightly laterally, and a sall caudal process protrudes posteroedially at the sixth festoon. CONSCUTUM (Fig. 1). Eyes arginal, flat, partially outlined by a few punctations. Cervical pits sall, slightly converging; internal cervical argins absent; external cervical argins a slight declination arked with a row of punctations; raised lateral borders sooth, shiny. Marginal line narrow, deep, and punctate, deliiting festoon 1 and extending anteriorly to posterior of eye. Posteroedian and posterolateral grooves well developed; posteroedian straight, narrow; posterolaterals begin as thin lines between festoons 3 and 4 and extend anteriorly as coa-shaped grooves slightly ipressed into the conscutal surface. Punctations nuerous, sall, those in external cervical argin and arginal line very slightly larger, but the overall ipression is of a conscutu covered throughout with uniforly sall punctations. LEGS (Fig. 1). Increase in size very slightly fro I to IV. Anterior projection of coxa I sharp, easily visible dorsally. VENTRAL SURFACE- SPIRACLE (Fig. 4). Elongate, narrow, acula situated near anterior argin; dorsal prolongation visible fro dorsu, not uch narrower than body of spiracle. ADANAL PLATES (Fig. 5): Usually sickle-shaped as in the illustration, but in soe ales ore straightsided with only an indication of being sickle-shaped. Accessory plates as in Fig. 5, but less well developed in soe ales. FEMALE (Fig. 2, 6-8) CAPITULUM (Fig. 6). Slightly broader than long, the length x breadth varying fro 0,86 x 0,83 to 0,85 x 0,82. BASIS CAPITULI (Fig. 6). Length fro palpal insertion to cornua apices varying fro 0,48-0,44 ; porose areas sall, indented, subcircular. PALPS (Fig. 6). Article I short, but visible fro dorsal surface. Article II longer than article Ill. BoDY (Fig. 2). Length (fro scapular apices to posterior body argin) x breadth varying fro 3,32 x 2,10 to 3,20 x 1,91. Marginal line usually deliits first two festoons, extending anteriorly as a deep, seta-lined trough to posterior argin of scutu. Colour dark reddish brown to alost black. SCUTUM (Fig. 2, 7). Outline ovoid, colour glossy dark reddish brown to black. Length x breadth varying fro 1,69 x 1,65 to 1,54 x 1,46 ; broadest at eye level. Eyes arginal, flat to very slightly raised. Cervical pits short, deep, converging; internal cervical argin shallow, converging initially then diverging; external cervical argin a slight declination well delineated by a cessation of punctations; raised lateral borders sooth, shiny with only a few punctations on the lateral argins and scapular areas. Punctations nuerous, sall, evenly distributed centrally, but few in anterior areas of cervical fields. LEGS (Fig. 2). Uniforly dark brown, not increasing in size fro I-IV. VENTRAL SURFACE- SPIRACLE. Short, rounded, with sall, broad dorsal prolongation. 206

3 JANE B. WALKER, J.E. KEIRANS & R.G. PEGRAM 1 FIG. 1-2 Rhipicephalus aquatilis sp. nov. [Onderstepoort Tick Collection 3143 i (WN99)]. 1. Male, dorsal view. 2. Feale, dorsal view. A. Olwage del. Scale bars represent 1 207

4 Rhipicephalus aquatilus sp. nov. (Acari: Ixodidae) FIG. 3-8 Rhipicephalus aquatilis sp. nov. (fro Tanzania Tick Collection WN99). Male: 3. Capitulu, dorsal. 4. Spiracle. 5. Adanal plates. Feale: 6. Capitulu, dorsal. 7. Scutu. 8. Genital aperture. SEMS by J.F. Putterill 208

5 I\) 0 <0 TABLE 1 Rhipicephalus aquatilis sp. nov.-aterial exained No. of ticks Depository & accession no. Host Locality d' 'i' Date of collection UGANDA Nuttall Tragelaphus spekei Entebbe (oo o4'n, 32 28'E) 9 Sept Nuttall 3949 a 1 1 T. spekei Luwafu (on Koja Experiental Stock Far). (c. oo 10'N, 32 47'E) May 1933 BM (NH) a 2 1 T. spekei Entebbe 11 Jan OP 3143 ii b 2 2 T. spekei Locality unknown? RML c (JGM/ AHRC 65/1045) 0 1 Panthera leo Nyabushozi, Ankole (00. 12'S, 'E) 9 Oct JGM/AHRC 67/ T. spekei Lake Mburo, Ankole (00 40'S, 30 56'E) 27 Feb JGM/AHRC 67/ P. pardus Lake Mburo, Ankole 27 Nov TANZANIA WN99 a, OP 3143 i b 9 7 d T. spekei Kaisho, Karagwe (01. 19'S, 30 37'E) (swap) 14 Aug BK/64 a 1 0 Bovine Nyakatoke village, Rubale Gobolola (01 36'S, 31 28'E) 8 July 1958 BK/77 " 1 0 Bovine Bukwale village, Kanyigo Gobolola (01 o1 'S, 31 44'E) 15 July 1959 KG/8 " 0 1 Bovine Kahanga village, Nyaishoze Gobolola (c 'S, 31 02'E) 26 July 1958 MW/40 " 0 1 Bovine Mbale village and Gunguli, edge of Sith Sound (03 04'S, 32 48'E) 28 Oct ZAMBIA RML c T. spekei Lake Bangweulu (11 o5's, 29 45'E) 1 Sept OP 3143 iii b(t.c. 737) 0 1 Bovine Liulunga (15 09'S, 23 1 O'E) 31 Mar OP 3143 iv b (T.C. 770) 0 1 Bovine Liulunga April1982 Natural History Museu, London. (Collection nos. WN99, BK/64, BK/77, KG/8 and MW/40 are in the Tanzania Tick Collection deposited in this useu) b Onderstepoort Tick Collection, Onderstepoort Veterinary Institute c U.S. National Tick Collection " 2 d'd' and 2 'i' 'i' fro collection WN99 have now been islaid Collector S.A. Neave W.F. Poulton R.W.M. Metta J.G. Matthyse J.G. Matthyse J.G.Matthyse J.G. Matthyse Mrs G. Tullock G.H. Yeoan G.H.Yeoan Vet. Guard Sospeta G.H.Yeoan R.G. Pegra R.G. Pegra (_ z OJ r ;:>:: (_ ;:>:: z (f) Qo Q -u (j) ;;:;:

6 Rhipicephalus aquatilus sp. nov. (Acari: Ixodidae) GENITAL APERTURE (Fig. 8). Situated between coxae II; V-shaped, ars of V gentle sigoid curves; area within the opening not bulging. IMMATURE STAGES. Unknown BIOLOGY IN THE FIELD To date we have seen 15 collections of R. aquatilis fro four host species in Uganda, north-western Tanzania and Zabia: cattle (six collections); sitatunga (seven collections); and one each fro lion (Panthera leo) and leopard (Panthera pardus) (Table 1, Fig. 9). The collections fro the sitatunga coprised 41 d'd' and 34 of R. aquatilis, while the eight collections fro the other three host species coprised only 2 d'd' and 8. are sei-aquatic, spending the greater part of their lives in dense papyrus, Cyperus papyrus, and reed beds, Phragites auritianus, in swap areas in water up to about a etre deep." The cattle fro which two of the collections in Tanzania were ade were grazing in siilar conditions. Those fro Bukwale village (BK/77) were at the edge of a swap with tall, coarse grass and patches of swap forest. Those near the edge of Sith Sound (MW/40) were in one of the seasonally inundated, shallow, internaldrainage grassland areas known as buga throughout Tanzania and aong lake shore rushes (G.H. Yeoan, unpublished data 1958; Yeoan & Walker 1967). In western Zabia, Liulunga-where two of the other collections on cattle were obtained-is in Mushibe woodland (Guibourtia coleospera), adjacent to the seasonally inundated Zabezi floodplain grasslands (Loudetia sp.) (Pegra eta/. 1986) , / i ACKNOWLEDGEMENTS We sincerely thank Mr A. Olwage for the line drawings of the ale and feale of R. aquatilis ; Mr J.F. Putterill for taking the scanning electron icrographs, Miss Heloise Heyne for printing these photographs, and Mrs A.S. Meiring for processing our anuscript for publication. This research was supported in part by National Institute of Allergy and Infectious Diseases grant A and a research fellowship at the Onderstepoort Veterinary Institute to J.E. Keirans.. - '"1... _, ( i \ i \ 0 ZAMBIA.. FIG. 9 Rhipicephalus aquatilis sp. nov.- distribution All the hosts fro which these ticks were obtained were located in lakeside, swapy or seasonally flooded areas. Nearly half of the were sitatunga. According to Skinner & Sithers (1990) "sitatunga REFERENCES KEIRANS, J.E George Henry Falkiner Nuttall and the Nut tall tick catalogue. United States Departent of Agriculture, Agricultural Research Service, Washington D.C.: U.S. Govern ent Printing Office (Miscellaneous Publication; no. 1438). MATTHYSSE, J.G. & COLBO, M.H The ixodid ticks of Uganda, together with species pertinent to Uganda because of their present known distribution. College Park, Maryland: Entoological Society of Aerica. PEGRAM, R.G., PERRY, B.D., MUSISI, F.L. & MWANAUMO, B Ecology and phenology of ticks in Zabia: seasonal dynaics on cattle. Experiental and Applied Acarology, 2: SKINNER, J.D. &SMITHERS, R.H.N Theaalsofthe southern African subregion. Pretoria: University of Pretoria. YEOMAN, G.H. & WALKER, JANE B The ixodid ticks of Tanzania. A study of the zoogeography of the Ixodidae of an East African country. London: Coonwealth Institute of Entoology. 210