This specimen, identified by Dr. G. Theiler, is the only one of this species from the Sudan. It represents an apparently rare intrusion into the western half of Equatoria Province from the Belgian Congo. Ecologically, the Yei area, except for a few hill masses, does not seem suitable for the survival of this mountain inhabiting species though other localities in the eastern high. lands of Equatoria Province might well meet its requirements. See A. superbum, REMARKS below. DISTRIBUTION A. pomposum is a highland tick of eastern Central Africa, adjacent parts of East Africa, and northern parts of southern Africa. See also REMARKS and IDENTIFICATION below. CENTRAL AFRICA: BELGIAN CONGO and RUANDA URUNDI (Nuttall and Warburton 1916. Seydel 1925. Robinson 1926. Schwetz 1927A. Bequaert 1931. Neitz 1947. Schoenaers 1951A. Theiler and Ro binson 1954. Note: Santos Dias 1953E refers most of these Congo reports to his A. superbum sp. nov. However, correspondence with curators reveals that he had not examined the specimens on which these references were based). EAST AFRICA: SUDAN (Hoogstraal 1954B). KENYA (See Note under IDENTIFICATION below). UGANDA (Hoogstraal 1954C). TANGANYIKA (Donitz 1909). SOUTHERN AFRICA: ANGOLA (Leitao 1942. Robinson 1926. Santos Dias 1950. Bacelar 1950. Sousa Dias 1950, this report referred to A. superbum sp. nov. by Santos Dias 1953E; see IDENTIFICATION below. Theiler and Robinson 1954. Rousselot 1953B). MOZAMBIQUE Robinson 1912*, 1926*. Santos Dias 1947A,1953B*,1954A,C*. Ac cording to Theiler (correspondence), A. variegatum govurensis Santos Dias (1950B), from the extreme north of Sul do Save Province, is synonymous with A. pomposum. Recently, Santos Dias (1953E) has agreed with this view; see IDENTIFICATION below 7. NORTHERN RHODESIA (Robinson 1926. and Robinson 1954). SOUTHERN RHODESIA Matthysse 1954. Theiler (See REMARKS below). HOSTS Domestic cattle are referred to as hosts of A. pompo sum by most authors, but Matthysse (1954) found it only on wild hosts, and then rarely, in Northern Rhodesia. Mules (Nuttall and War_ burton 1916. Robinson 1926. Sousa Dias 1950). Horses (Theiler, unpublished records). Sheep, goats, dogs, donkeys (Sousa Dias 1950). Man (As synonymous A. variegatum nocens: Robinson 1912* and subsequently frequently quoted without additional observations). "Striped antelope" (Dönitz 1909). Sable antelope, roan antelope, and eland (Robinson 1926, Schwetz 1927A; Congo specimens in Onderstepoort collection). Hartebeest, kudu (Robinson 1926). Zebra (Schwetz 1927A). Buffalo (Jack 1942*). Warthog (Schoenaers 1951A). Ankole topi, Damaliscus korrigum ugandae (Hoogstraal 1954C). The nymphal specimen from a monkey, mentioned by Santos Dias (1954), should be checked against A. variegatum. "Wild hosts only in Northern Rhodesia" (Matthysse 1954). BIOLOGY See REMARKS and IDENTIFICATION below. All authors who refer to collecting localities for A. pomposum stress the fact that it is a highland species. *This record should be read in conjunction with statements in REMARKS and in IDENTIFICATION below. DISEASE RELATIONS MAN*: A. pomposum is said to attack African children's heads and causes sloughing of the skin. This has not been substantiated. CATTLE: Inflammation and sloughing of mammae. (Rickettsia ruminantium). HORSES: Pyolymphangitis. Heartwater REMARKS According to Robinson (1912*), A. pomposum (= A. variegatum nocens) occurs in the Rhodesias and Mozambique chiefly in bushveld from 2000 to 3000 feet elevation and seldom above 4000 feet. He further stated that this tick is notorious for the damage it does to stock in the Rhodesias, where it is known as the "Pyaemia tick”. However, Morris (1933,1935,1936) attributed "tick-pyaemia" in Northern Rhodesia to A. variegatum. In Southern Rhodesia, Jack (1918) referred "ixodic lymphangitis" to A. variegatum, Sinclair (1916) associated skin diseases of cattle with A. variegatum, and Jack (1928,1937,1942) also mentioned only A. variegatum with reference to abscesses and sloughing of the hosts skin. In his first two papers Jack did not differentiate between A. variegatum and A. pomposum, but in his 1942 report he stated that the local highlands where A. pomposum would be expected to occur, are free of amblyommas but that some male specimens of A. variegatum from the lowlands may show a tendency to resemble A. pomposum. See also IDENTIFICATION below. Theiler (correspondence) calls attention to the following facts that may modify many of the above reports concerning A. pomposum. Robinson's (1912,1926) remarks concerning A. pomposum in Mozambique and Southern Rhodesia are based on statements of Mr. E. M. Jarvis. Jack's records for Southern Rhodesia apparent ly are quoted from the same source, for no further data are presented. The extensive Onderstepoort collection has no specimens from Southern Rhodesia. Theiler's correspondence with Dr. Lawrence, Assistant Director (Research) of the Southern Rhode sia Veterinary Department, indicates that he is not aware that A. *This record should be read in conjunction with statements in REMARKS and in IDENTIFICATION below. pomposum occurs in this territory and that he considers the Jarvis statements as "sheer nonsense". It appears, therefore, that earlier literature records for A. pomposum in Mozambique and Southern Rhode sia are open to question. Wherever A. pomposum occurs it seems to be present in good numbers. Its distribution, so far as Theiler has determined (correspondence), is mainly in the Rhodesia Highland Savannah type of vegetation, certainly not in the moist vegetation of the Umtali... Melsetter district and adjoining Manicaland. More extensive search for and study of this species is required. Statements regarding damage to cattle and to children by this tick in Southern Rhodesia appear to be questionable. Sousa Dias (1950) writes concerning A. pomposum, which is com mon in the Angolan highlands, as follows: "It is considered by breeders to be one of the most harmful ectoparasites of stock for it causes wounds that are most difficult to heal. It is probable that (this tick) is one of the factors that favors the dispersal of bovine dermatoses so common in Angola". He surmises, that A. pomposum is a heartwater vector in Angola inasmuch as it occurs in heartwater areas in the absence of other recognized vectors. Neitz (1947) showed that A. pomposum is a vector of heartwater_7. A. pomposum is close morphologically to A. lepidum and to A. variegatum. The latter, biologically, is a most versatile tick except that it shuns desert and rainforest areas. A. lepidum is a semiarid country and savannah species. A. pompo sum appears to be chiefly a highland species. See also remarks on See also remarks on A. superbum in section below. A gynandromorph of this species has been described by Santos Dias (1954). Schulze (1932C) discussed certain features of the ornamentation of A. pomposum in relation to other species in this genus. |