RHIPICEPHALUS LONGUS Neumann, 1907(A)*. (Figures 277 to 280) THE SCIMITAR SHIELD CAPE BROWN TICK L NỞ EQUATORIA PROVINCE RECORDS 2 3 Laboni Syncerus caffer aequinoctialis Feb Kheirallah Syncerus caffer aequinoctialis Mar (SGC) R. longus is not known from other Provinces of the Sudan. DISTRIBUTION Although R. longus appears to be chiefly a Central and West African tick, scattered populations occur in East Africa and in the northern part of southern Africa, apparently in more humid areas. The possibility that some specimens in the reports listed below have been confused with R. capensis must be considered. See footnote below. WEST AFRICA: NIGERIA (Zumpt 1942B. (Zumpt 1942B). LIBERIA (As R. falcatus: Unsworth 1952). TOGO CENTRAL AFRICA: CAMEROONS (Zumpt 1942B. Rageau 1951,1953A, *R. falcatus Neumann, 1908, is a synonym of R. longus, but few literature records of R. falcatus can be assumed to refer to R. longus. The name R. falcatus was long used indiscriminately as a "catch_all" for heavily punctate rhipicephalids with sickle shape ad anal shields and many species were lumped under it. SOUTHERN AFRICA: ANGOLA (Zumpt 1942B. Theiler and Robinson 1954. See also HOSTS below). NYASALAND (All as R. falcatus: Neumann 1908C. Old 1909. Warburton 1912. Wilson 1950B. See also HOSTS below). MOZAMBIQUE (As R. falcatus: Theiler 1943B, 1947. Santos Dias 1952H,1953B). HOSTS Larger domestic animals and wild game animals serve as hosts of R. longus. Available data are not extensive enough to demons trate further host predilection within this range. Domestic animals: Cattle (Neumann 1907A, Schwetz 1932, Fain 1949, Rageau 1951,1953B, Rousselot 1951). Dogs (Nuttall lot 1950A from Angola in BMNH. Zumpt 1942A, Rageau 1951,1953B). Horses (Fain 1949, Wilson 1950B). Pigs (Fain 1949, Santos Dias 1952H,1953N). Wild animals: Buffalo (Nuttall lot 434A from Semliki Plains in BMNH. Bequaert 1930A,1931, Zumpt 1942, Theiler 1943B, Fain 1949, Wilson 1950B, Rousselot 1951, Santos Dias 1952H,1953B, and Sudan records above). Eland (Bequaert 1931). Sable antelope (Zumpt 1942A, Santos Dias 1953B). Roan antelope (Nuttall lot 227 from Nyasaland in BMNH. Wilson 1950B). Lichtenstein's hartebeest (Santos Dias 1952H,1953B). Wild pig (Schwetz 1932, Fain 1949). Warthog (Nuttall lot 1099A from Nyasaland in BMNH. Zumpt 1942A, Wilson 1950B, Santos Dias 1953B). Jackal (Fain 1949). Lion (Rageau 1953B). BIOLOGY R. longus appears to be a tick of somewhat more humid areas than the closely related R. capensis, or else it is a rainy season species, while R. capensis is a dry season form. The geo graphic range of the two, formerly considered to be West African and East African respectively, is now known to include some areas, Mozambique and Nyasaland, in which both occur, though the data are not sufficiently detailed to indicate whether they are found together or in different seasons or ecological zones within these political boundaries. Unstudied. DISEASE RELATIONS REMARKS Schulze (1944, p. 410) mentioned this species in a study of tick integument. Zumpt (1942B,1950A) considered R. longus to be a West and Central African subspecies of R. capensis but has stated more recently (1950 correspondence) that, after having received additional material from Mozambique and Nyasaland, he has come to regard each as a separate species. Santos Dias (1953D) confused R. longus and R. simus senega lensis and, in so doing described for the latter yet another species, obviously synonymous, R. pseudolongus. In an effort to determine his ideas concerning this species, we sent him (1954) Sudan specimens consisting of numerous R. simus senegalensis which were returned marked as R. longus, and all my available R. longus, which were returned as R. capensis pseudo longus. R. longus is closely related to R. capensis, as already noted. Zumpt (19428,1950A) stated that the range of "R. capensis capensis" includes the Sudan. This is most probably in error. R. simus senegalensis males are mostly readily separated from those of R. longus, but individuals of the former species that have exceptionally heavy interstitial or secondary punctation may momentarily be confused with R. longus. Turning such a specimen obliquely to the source of the light will reveal the typical arrangement of larger posterior punctations as described for R. simus senegalensis (cf. page 759) among the smaller, more superficial, secondary punctations, a characteristic not associated with R. longus. Both species may occur on the same host. IDENTIFICATION Male: This is a fairly large, robust tick (up to 6.0 mm. long and 3.5 mm. wide), usually jet black in color (smaller spec imens often reddish brown) with reddish brown legs. It has def inite, long, deep lateral grooves but the narrow posteromedian groove is vague or obsolete and the paramedian grooves, if present at all, are even more vague. The scutal punctations are distinctive, being of a uniformly shallow, small or medium size, densely and closely distributed in irregular lines everywhere except in the scapular areas, on the festoons, outside the lateral margins, and in a narrow area just inside the lateral margins; most punc tations are clean and discrete. Shallowness of punctations varies among individuals, but the pits are never deep and are sometimes quite superficial. The overall appearance is one of regularity of punctations within the impunctate periphery bordering the lateral grooves; no pattern of larger and deeper punctations is visible among the normal punctations. If the punctations are exceptionally shallow, those in the area of the posterior grooves tend to be slightly larger and deeper than elsewhere. Coxa I has a stump showing dorsally, but no dorsal process. In engorged specimens, the three median festoons protrude. The adanal shields of typically large specimens are sickleshaped, with a deeply curved inner margin, but in smaller specimens this feature may be con siderably reduced (at the moment, I would not know how to dis tinguish runt specimens with narrowly elongate, uncurved adanal shields from small specimens of R. capensis). Female: This sex (which, so far as known, cannot be dis tinguished from R. capensis) has a subcircular scutum densely beset with uniform, fairly large punctations very much like those of the male, but usually somewhat larger, deeper, and more dense; these punctations are evenly distributed in the depression within the lateral grooves but are sparse or almost entirely absent in a narrow area along the posterior margin and on the elevated ridge outside the lateral margins. Note: A male and a female cotype of R. falcatus examined in British Museum (Natural History) collections conform to the description of typical specimens of R. longus as provided above. |