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viduals hatched from unfertilized females. Oviposition in un_ fertilized females was much delayed and the interval between hatching and molting of their progeny much prolonged. All prog_ eny were females, but when these were mated with normal males both sexes were represented in the subsequent generation.

According to Cunliffe, Q. moubata and Q. sayi ' may copulate but the resulting eggs are unfertile. This s contradicted by recent, unpublished findings of Dr. G. E. Davis who writes (correspondence) as follows: ‘I have found that the interbreeding of these two species not only results in progeny but in fertile progeny when the products of the first interbreeding are allowed to interbreed among themselves‘.

The foregoing is a reasonably complete though brief sumary of what is known about the life cycle of 0. moubata. Before lean; ing this subject, attention should be called E3 the additional temperature and humidity studies discussed under Environmental ada'tabilit below for these factors exert considera e uence on Ehe life cycle.

Ecolog
Environment and Domestic Habitats

The ecology and distribution of 0. moubata, as sumarized in the paragraphs below, has always been-considered in the light of domestic populations. The significance of the increasingly more numerous reports of the eyeless tampan in large animal burrows from the Sudan to South Africa awaits to be determined. Should it eventually be found that these two populations are a single biological entity that has happened by chance to occupy one or the other habitat, the conclusions of early workers, who believed that man has been wholly responsible for carrying this tick out_ ward from its primitive range in the East African lowlands, will have to be modified.

The arid environment preferred by domestic populations of O. moubata restricts their presence to dry, permanent huts and structures where people gather. In its probable original area, the Somali Arid District and possibly the East African Lowland

District, this tampan appears to be mre uniformly distributed than elsewhere. These details, however, await confirmtion.

Outward from the Somali District the eyeless tampan normally inhabits dry structures in savannah areas, especially those with sandy or sandy clay soils with light woods. Riparian forests through grasslands, dense forests, and areas of heavy rainfall are usually free of the tick, although exceptional human culture patterns sometimes allow important foci to develop in dry habi. tats in these situations. Such details have been described most vividly by workers in the Belgian Congo (Bequaert l9l9,l93OA; Rodhain l9l9A,B,l922A,C; Ghesquiere l%2; Schwetz l932,1933A,l942, 1943; and others).

0. moubata appears to have spread gradually outward from somewhat drT areas of East Africa along min paths of human trav. el. Old Arabic slave routes are considered to have been largely responsible for its initial distribution by man (Dutton and Todd 1905A; Bequaert l9l9,l930A). Although especially conmnn along important old and new travel arteries, the tampan is often mark. edly absent a few miles distant. Exceptions do occur. For instance, Koch (1905 ) reported 2. nnubata from the Rubafu Moun. tains a.nd elsewhere in villages away from trade routes in Tanga. nyika. More and more exceptions should occur as travel becomes easier and quicker, tribal customs disintegrate, and labor de. nnnds call numerous individuals, with possibly tick...infested personal effects, far from their usual range of activities.

2. moubata is said to be frequently concealed in sleeping nnts, spare cIothing, or baskets and thus may be transferred easily from one area to another. South African authorities blame the tampan's increasing spread in the Union on migratory laborers from Nyasaland and Portugese territories. In the Belgian Congo it has been found in potato baskets sent to distant markets (Ghesquiere 1922) and is frequently introduced in goods sent from the lowlands to villages at high elevations (Schouteden 1928). This tampan is common in fish baskets of vendors bicycling from Lake Nyasa and Lake Shirwa to villages in other parts of Nyasa. land (Hardman 1951). Christy (l903A,B) collected specimens in salt bags being transported between Lake Albert and Tete.

Where soil consistency permits, the eyeless tampan usually burrows to a depth of approximately an inch; but in soil cracks it burrows deeper. On the groud surface it may rest uder any object that offers shelter. If soil is too wet or too hard for burrowing the tick is induced to crawl up walls and seek concealment behind hanging objects, in cracks or in ceilings. The tampan's presence is often indicated by spots or streaks from its excretory products left on walls.

In Kenya, 0. moubata ranges from sea level to an elevation of 8000 feet (1Zwi_T%T§Ie ) or of 9000 (Heisch 1950A). In Ethiopia, Manson-Bahr (1941) stated it is absent above 6000 feet elevation ad Scaffidi (1937) reported that it is not present above 7150 feet.

This tampan survives in the Transvaal Highveld in spite of ‘bitterly cold winters“ there GDe Meillon 1940, Ordman 1941). Theiler reports (correspondence) that winter day-temperatures in the Transvaal highlands are “high enough? and that residents bring fires into their huts at night.

In certain Congo areas, Flamand (1928) found 0. moubata thriving at about 10,000 feet elevation. Schouteden (1923) replied that these populations are the result of repeated introductions in goods from the lowlands. While tampans survive at these altitudes, they do not reproduce there.

Incidental to a disease transmission study, Van Oye (1943) reported that 0. moubata dies in less than 24 hours at temperatures of 0°C. to F5. (Zl°F.). However, Burgdorfer reports (conversation) that he has maintained tampans at 3°C. for at least ten days without death of the specimens. Feng and Chung (1938) maintained these ticks alive for months at 5°C. to 800. It is obvious that the critical temperatue range for the survival of Q. moubata requires further study.

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The absence of O. moubata from certain volcanic areas in the Congo was thought by-Van Saceghem (1923) to be owing to an unfavorable chemical action produced by contact of lava with oxygen of the air. Dr. J. Bequaert reports (conversation) that these areas are all at high elevation and that he believes altitude to be the important limiting factor in these volcanic areas.

Wallace (1913) noted that in Northern Rhodesia 0. moubata abounded in hilly country and on the Mpika plateau, but was absent in the hot Lnangwa Valley. The combinations of temperature and relative humidity factors that restrict O. moubata in nature are still poorly known.

[graphic]

Dutton and Todd (l905A,B) and Bequaert (1919) mentioned an exception to the general rule that Q. moubata does not occur in deeply forested, humid areas. The explanation was that inesta_ tions in the Upper Ituri Forest are in wooded areas where araku isized Negro inhabitants have cut over extensive forests and constructed villages of dry, permanent buildings. In these, ticks brought along the Arab trade route have been able to survive in spite of inclement conditions outside.

Another notable exception to the usual finding that O. moubata is absent from high rainfall areas is cited by Walton (19‘50AT."'I“n Meru District, Kenya, even under unfavorable high rainfall and humidity conditions, large populations of this tick suvive in some huts. The predisposing factor is that the local tribes sleep on dry, raised mud beds. Hosts are readily accessible to ticks and fires near beds keep an area of ground dry enough to meet the tampan's requirements. Agricultural implements in these huts provide additional shelters behind and under which the ticks also hide. Contrary to usual advice to remove domestic animals from human habitations, Walton believes that under Meru District conditions animals provide enough extra humidity and pound floors hard enough to reduce tick populations. Under more usual conditions, however, this suggestion would probably not be an effective one. In some Meru District huts, where sticky soil has a humidity of about 9q%, it is difficult for ticks to burrow and few specimens are found. Whether this investigator searched for ticks climbing walls or pillars in these huts is not stated.

kt Kisumu, Heisch (1950) found that the size of tampan popu. lations in huts is uninfluenced by seasonal variation in rainfall.

Knowles and Terry (1950) collected hundreds of nymphal tampans on fowls kept in human habitations in Tanganyika, but Phipps (1950) asserted that chickens are seldom infested there. Careful research into the highly practical problem of relationship of chickens to

tampan infestation is indicated. Rodhain (l919A) reported finding avian blood in specimens taken from an empty outhouse inhabited by chickens. It has been suggested that periodic forays by chickens

into infested huts may partially reduce the tick population in these places.

Aside from usual indigenous dwellings, the eyeless tampan is frequently encountered where people congregate. In Uganda, rest camps often have been burned because of heavy infestation (Bruce et al l9ll); jails and semipermanent buildings used by itinerant Ifrizans are frequently infested (Hopkins and Chorley 1940). In Kenya, 0. moubata is “alarmingly abundant" in labor camps (Jepson 1947) aid military barracks are specially constructed to resist infestation (Hyd 1945). The tampan is a coffeehouse inhabitant in British Somaliland (Anderson 1947). In a Somaliland focus of relapsing fever, all patients were found to be members of a political party the headquarters building of which was infested with O. moubata and had escaped insecticiding when other structures were dusted lfipparoni 1951). In South Africa, it is an important pest in “lesser mine“ labor camps but in larger mines, such as those at Johannesburg where sanitary measures are practiced, the tick is absent (Ordman 1941,1943).

In contrast, the c1osely.related eyed tampan, Q. savi ', usually lives away from habitations, under trees, in village squares, near wells, in stockades, or in shaded spots along trails where men and animals rest.

There are but few reported observations of 0. moubata living under outdoor conditions approaching those favored by 0. savi n '. In 1916, Belgian colonial troops operating in Urundi, whi e en ing under a row of mango trees that had bordered buildings des. troyed some six years earlier, recovered several specimens from the soil around the roots of these trees. The assumption was that these ticks had survived since the destruction of the near. by buildings some years earlier (Rodhain 1919B).

Ordman (191.1) listed two cases of the eyeless tampan in South Africa living "in and uner trees“, but further conclusive evidence is not presented.

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