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The Smian distribution picture is a curious one. Although we have a fair number of collections from cattle in that half of Equatoria Province that is east of the Nile, none contain spec. imens of B. annulatus except two from high altitudes ( from Katira, 3500 feet eIevation, 19 from Nagichot, 6500 fee eleva. tion) and one from Torit, at the general two thousand foot level of the plains in this area. Yet collections from the southern part of Upper Nile Province, which is just north of the east bank of Equatoria Province, include a good number of specimens. Cli. matic, faunal, or floral differences can hardly account for the rarity of B. annulatus in Torit and Juba districts. The most easterly reco~, Upper Nile Province, is on the Ethiopian frontier (7°47'N., 33°0l'E.). 0n the west bank of the Nile, this species is here recorded from several localities to as far north as Talodi, Kordofan Province (l0°37'N.).
Some specimens reach the Halfa Quarantine station in Northern Province but Boo hilus ticks have never been collected from indigo. nous cattle in Nofihern Province.
Thus far we know B. annulatus only from West Africa, Central Africa, and certain parts of southern Sudan near the periphery of East African biotic Provinces. As early as 1905, Donitz recognized that this tick inhabited only "tropical Africa" a.nd was absent in eastern and southern Africa. He tentatively applied the name B. australis Fuller to it, although he stated clearly that he could not differentiate African material from descriptions of American B. annulatus. Unfortunately, he had no American specimens for comnari son for it appears that this perspicacious student might otherwise have saved future generations much misunderstanding. Instead, this species subsequently has been either completely overlooked or subjected to numerous ambiguous remarks and names.
Many African specimens undoubtedly have been identified as Q. decoloratus, and earlier workers who have recognized specimens as dflferent from l_3. decoloratus have referred to them by various names. The actual species with which various investigators were dealing cannot be determined without seeing their specimens. For instance, Nuttell's lots identified as B. australis, which have
been examined in British Museum (Natural History), contain both B. decoloratus and B. annulatus.
§. annulatus is a North American cattle tick that one may assume e¥I§I5EII§ parasitized deer and buffalo. It also has been introduced into the Mediterranean basin. In North Africa and the Near East, it frequently is referred to as B. calcaratus (Birula, 1894), to which Minning appended several subspecies. These all appear to be the same as American and African populations of B. annulatus. The name also has been used by students of the OrIental auna examination of pertinent specimen material is indicated to establish the validity of these identifications.
Records presented below are the only ones from Africa that are known to pertain to B. annulatus, with a few additional, annotated references that Eight 55 pertinent. Quite possibly other isolated populations are maintaining themselves outside of the pesently recognized range of the Texas fever tick in the Ethiopian Faunal Region, having been introduced on cattle from West or North Africa, the Near East, or North America.
wssr AFRICA: NIGERIA (Hoogstraal 195/.0). LIBERIA (Specimens from cattle at Harbel, Firestone Rubber Company Plantation, H. A. Beatty le it; 1412 collections). smmu LEONE (Hoogstraal 1951.0). PCRT GUINEA: B. (= Margaropus) annulatus listed by bbnteiro a Costa (1926) and Sant'anna Barreto (1929); quoted by Tendeiro (195lA), but not subsequently repeated in faunal lists by this author although it would not be suprising to find this tick herei7
NOTE: Records below are for QB. congolensi '.
CENTRAL AFRICA: FRENCH EQUATORIAL AFRICA (Minning 1934. Rous~ ot B. heiler and Robinson 1951.). cmmaoous (Rageau l953A,B). BELGIAN CONGO (Theiler and Robinson 1954. Minning 1934 stated, apparently as a guess, that the B. annulatus calcaratus specimens of Newstead, Dutton, and Todd 1909, fron1Coq§Ilh§tville,
are TB. coEgolensis').
EAST AFRICA: SUDAN (Hoogstraal l95LB,C. Balfour l9llF referred to NE. australis" in the Sudan, but since he also stated that B. decoloratus is absent there his remarks are difficult to
Cattle (All references). Rarely giant eland and domestic donkey (Sudan records above). In America, other domestic animals, deer S and buffalo have been reported as infrequent hosts (Cooley 1946 .
Like other boophilids, the Texas fever tick is a single host parasite. Its life cycle has not been studied in Africa, where it is not known to occur under cold conditions.
Lfter dropping from the host, the female commences oviposition in about three or four days but after twenty to forty days in winter (southern United States). The oviposition period ranges from eight or nine days in summer to 42 days in winter. The mxmber of eggs average 1911, with a maacinnnn of 3806. With abundant moisture, eggs may hatch in as little as from 17 to 21 days, but up to 1.1. days is more common. Winter incubation may require between five and six months. A few hours after hatching, larvae collect in masses at the tip of grass, and may remain alive from 49 to 159 days awaiting a host. Once an animal is found larvae prefer. entially attach to the legs, belly, or dewlap, but if numerous they are found everywhere on the body. The larvaJ.._nymphal molt occurs seven to twelve days later and nymphs molt to adults five to ten days afterwards. Females feed for from four to fourteen days, during which tim they mate, and then drop to the ground, oviposit, and die. These data are extracted from the very com. plete work of Hunter and Hooker (1907) in the United States.
Most African specimens are from collections containing more numerous §. decoloratus, with the exception that during the rainy season the mm rs o B. annulatus have in some instances exceeded those of §. decoloratu-s‘. In Eameroons (Rageau 1953B), this tick is less common EE 5. decoloratus but both species are found to.gether. Our first s1_1sp'i'ci' on, that this might be a species ac
climated to humid West Africa, is negated by finding it in Sudan localities with long, severely hot, dry seasons. The Texas fever tick occurs in the Sudan in areas with from 800 mm. to 1500 mm. annual rainfall.
The ecology of Q. annulatus is unstudied in Africa and the results of research on tfls su53ect are awaited with considerable interest. In North and Central America, §. annulatus is entirely a tropical and subtropical tick that dies out when Introduced into the northern states.
Unstudied in Africa. B. annulatus in America is the famed vector of Texas fever of cattle lgagsia bigemina).
Minning (1934) considered West African populations to differ from New World B. annulatus and called them B. co olensis. Nu... merous _l§. anmzlatus specimens from the United a es an entral America have en examined in collections of British Museum (Natural History), Roclqr Mountain Laboratory, Museum of Comparative Zofilogy, as well as Louisiana material kindly presented by Dr. F. C. Bishopp from United States Department of Agriculture collections. None of these can be distinguished from African "_1§. co§golensis".
The chief characters presented for differentiating males are the pointed outer spur of coxa I of "§. co lensis" and the blunt outer spur of coxa I of Q. annulatus. In a %ew Brican specimens this spur is blunt, in many Erican specimens pointed. The American specimens in the Nu:tta‘Ll collections at British Museum (Natural History) are mostly blunt..spurred with few pointed_.spur specimens, but those at the Rocky Mountain Laboratory in Montana are almost entirely pointed...spurred. Specimens from Louisiana in the present collection have pointed spurs. It is evident, therefore, that this character is a variable one with no diagnostic significance as to species. The shape of the eyes of African and American specimens is similar. Examination of other so called dif.
ferentiating characters has also failed to reveal differences.
Similarly, no points of differentiation may be detected be. tween female specimens from Africa and America. The chief diag. nostic characters proposed for these, arching of the eyes and shape of the distal margin of the third palpal segment, appear similar, as are all other morphological features of specimens from both continents. Minning stated that the scutum of Amer. ican B. annulatus bears hairs and the scutum of ‘B. co olensis" does hot. §veral African specimens with scutal hairs & some American B. annulatus without scutal hairs are available, though they may have Been rubbed off the latter.
Theiler (194312) has already observed that the relation of the position of the eye to scutal margin in Boophilus ticks is subject to variation according to degree of engorgement. As already stated (page 296) no differences between length/width ratio of the female scutum can be determined in field..collected material of each species.
As stated above, it appears that there are no constant differences between American and African populations of B. anrru... latus. Likewise, it is impossible to differentiate betw'e'en_Er.. ican and African populations of B. annulatus, and specimens col. lected in North Africa, seutherh‘mmie1E1epe, the Near East, which Minning loc. cit.) referred to as B. schulzei and as B. calcara. t_u_s subspp. —- - _
In their classic work on this parasite in America, Hunter and Hooker (1907) open by observing -It is safe to state that no more important problem than the eradication of ...... (B. annulatus) confronts the farmers of any country. Not only the cattle raising industry but the whole economic condition of a large section of country is affected‘.
The Texas fever tick is now completely eradicated from the United States except for periodic introductions from Mexico, where it still exists. At the turn of the century it ranged through Mexico and the sixteen southern states of the United States from the Atlantic to the Pacific. The history..ma1cing discovery by Smith and Kilbourne (1893) that Babesia bi emina is the cause of Texas fever of cattle was fo].IB@"'5y tfieir finding that this tick is the vector. The life history and morphology of the tick have been reported handsomely by Curtice