RHIPICEPHALUS CUSPIDATUS Neumann, 1906 (Not R. CUSPIDATUS sensu Zumpt, 1950A)* (Figures 257 to 260) THE WEST AFRICAN WARTHOG BROWN TICK DISTRIBUTION IN THE SUDAN Bahr El Ghazal: Galual Nyang Forest, 150 and 31og from two warthogs, Phacochoerus aethiopicus subsp., and lo from ground, 21 and 23 February 1953, H. H. legit; 200. 600, same locality and host species, 7 June 1953, E. T. M. Reid legit. These are the only specimens of this interesting West African tick from the Sudan. DISTRIBUTION This West African warthog and aardvark parasite ranges eastward as far as the western part of southern Sudan. WEST AFRICA: FRENCH WEST AFRICA (Neumann 1905,1911. Theiler 1947. Rousselot 1951,1953B. Specimens from Fort Foureau and French Sudan, collected by Rageau and Rousselot, are present in the Theiler collection. It seems likely that the "R. complanatus" reported by Fiasson (1943B) from wild pigs refers actually to R. cuspidatus. PORTUGESE GUINEA (As R. sp.: Tendeiro 1948. As R. cuspidatus: Tendeiro 1951A,E,19520,1953,1954). CENTRAL AFRICA: CAMEROONS (Rageau 1953A,B). EAST AFRICA: SUDAN (Hoogstraal 1954B). Note: Stella (1940) listed R. cuspidatus from the Harrar area of Ethiopia. Pending further investigation, this record is considered questionable. *See REMARKS, page 632. HOSTS Warthogs, Phacochoerus aethiopicus subsp. (Neumann 1906,1911, and Sudan records above). Aardvark, Orycteropus afer senegalensis (Rousselot 1951,1953B, Tendeiro 1952). BIOLOGY It seems strange that this large tick from much-hunted warthogs should not have been more often reported from West Africa, though misidentification of specimens may account for this situa tion. DISEASE RELATIONS Ten of the above-mentioned Sudanese female specimens were inoculated into mice and guineapigs in the Cairo laboratories of Naval Medical Research Unit No. 3, for attempted isolation of viruses or rickettsiae. The host animals produced no sign of infection. It is claimed that specimens naturally infected with Q fever (Coxiella burnetii) occur in Portugese Guinea. REMARKS It was impossible to identify with certainty the Sudan specimens and some were sent to Dr. Theiler. She had received sim ilar material from French West Africa (noted above) and found that it corresponded to Neumann's (1906) description of R. cus pidatus but differed markedly from Zumpt's (1950A) interpreta tion of this species. Thereupon she sent the French West Africa specimens to Dr. D. R. Arthur for comparison with the R. cuspidatus type specimens in the British Museum (Natural History). He found these to be the same. What the tick reported by Zumpt (loc. cit.) as R. cuspidatus should be called is not known. R. cuspidatus falls into the subgenus Rhipicephalus (sensu strictu) of Zumpt (1950A) and not in Rhipicephalus in which he placed the species attributed by him to this name. IDENTIFICATION Males are readily recognized by the unique internoposterior curved or straight, pointed projection of the adanal shields, which reach to the festoons. (Slight variations in these projec.. tions have been illustrated by Tendeiro 1951E). The width of the adanal shields, which is almost half as great (at the posterior two-thirds) as the total length, is also distinctive as is the broadly triangular shape of the anterior two thirds, the acutely rounded and posteriorly sloping posterior margin, and the concave emargination of the posterior half of the inner border. Accessory shields are absent. Dorsally, a small rounded (not pointed) dorsal projection of coxa I is visible. The scutum is remarkably flat and broad, three-fourths as wide as its length from scapulae to posterior margin; its surface is smooth except for twelve to twenty widely scattered, large, deep punctations, six or eight small, deep ones, and two short, posterior rows of three or four adjacent, large, and deep punctations. Many specimens have one, two or three mild longitudinal depressions at one place or another on the scutal surface; these are obviously due to injury, crowding, malnutrition, or molting conditions. The deep lateral grooves, which are marked by a row of large, adjacent punctations, begin at the first festoon and extend to the level of coxa III; thence they continue anteriorly as a curved row of four equidistantly spaced, large, deep punctations. The very deep cervical grooves are parallel or slightly convergent and short, reaching only the level of trochanter II. The impunctate basis capituli is three times as wide at its anterior third as its total width. Unfed specimens are reddish brown, engorged individuals are an intense black with reddish-brown legs. Overall length varies from 3.50 mm. to 4.90 mm.; width from 1.98 mm. to 2.54 mm. Females unengorged average 4.40 mm. in overall length and 2.70 mm. in width; our largest engorged specimen is 11.00 mm. long and 6.30 mm. wide. The scutum is distinctly wider than long; lateral margins diverge gradually to the midlength of the scutum from whence they rather abruptly converge as a straight or slightly sinuous posterior margin merging with the narrowly blunt posterior margin. The cervical grooves are very deep and convergent, and reach the midlength of the scutum; thence they continue as very shallow, divergent grooves extending to or almost to the posterior margin. Lateral grooves as such are absent; their place is marked by three to seven very large, deep punctations that may be either free or in a shallow depression; the lateral field beyond these grooves is more or less abruptly raised. The scutum is slightly depressed between the lateral punctations and the shallow exten sions of the cervical grooves, but its intense black surface is otherwise marked by only four to seven large, deep, scattered punctations. The basis capituli is three times as wide as long and widest at its midlength; the porose areas are oval, vertical (not tilted), about twice as long as wide, deep, separated by a distance of one and a half times their own length, and extend from almost the posterior margin to just past the midlength of the basis capituli. Ventrally, it is important to note that coxa I is not deeply divided but that its posterior margin bears two robust spurs; the broadly triangular internal spur is not quite so long as the more narrowly triangular external spur and the division between these two spurs is equitriangular with the internal spur. |