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to find evidence of spirochetes in domestic fowls from tampan infested dwellings in Tanganyika, a suggestion that these ticks do not feed on fowls or do not transmit these organisms to fowls,

or else that Borrelia duttonii does not survive in fowls in nature.

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Along with A. rsicus, Mitscherlich (1941) discussed the ravages of_Q. mofibata in chicken houses in the Union of South Africa and in Southwest Africa Q: Deutsch Sddwest Afrika). It is not, however, clearly stated that this writer actually saw eyeless tampans in these situations. His remarks give the impession of being based on the assumption that O. moubata is an important parasite of domestic chickens.

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A wild relative of the domestic pig, the warthog, Phacohoerus aethio icus subspp., is a normal host of_Q. moubata under conditions ot influenced by man. An African boy in Northern Rhodesia has been observed emerging from a warthog burrow with about thirty nymphs biting him (Lloyd 1915). During a survey of the plains south of Lake Edward in the Belgian Congo, Schwetz (1933).) dis. covered that 0. moubata was abudant in warthog burrows but rare in native huts. Ch5rIey (1943) found over forty specimens crawling on a warthog shot in Uganda. He stated (personal conversation) that all these specimens were nymphs. Heisch and Grainger (1950) found nuerous specimens in widely scattered warthog burrows in Kenya and presented a theory on the relationship of wild and domestic populations, discussed below in the section on “Wild” Habitats, under Ecology. A single specimen from a Northern Rhodesian warthog and a large lot of nymphs from a Nyasaland warthog burow have been reported from material in the Nuttall collection (Hoogstraal 19540). Warthogs are also hosts in the Sudan, as noted above and reported earlier (Hoogstraal 1954B). These mamals also have been noted as hosts in Mozambique (Santos Dias 1952B,

19533 ).

In certain areas of Tanganyika, infestation of warthogs and other large mammals is well known in some quarters (Walton 1953). Walton described a warthog burrow in which 41 hungry later.stage nymphs and adults were found; stomach blood smears from these gave a positive reaction to pig antisera. O. moubata was also discovered in three other warthog and porcupine Burrows in foot. hills of the Usambara Mountains. Literally hundreds of nymphs and adults emerged from the floor and ceiling to attack Walton and a friend when they entered some of these burrows. Subsequent. ly, specimens were found in six other burrows and in two hollow baobab trees that were used from time to time as retreats by var. ious kinds of animals. Smaller burrows in the Usambara tbuntains area, presumably belonging to the giant forest rat, Cricetomys sp., were uninfested.

More recently in Tanganyika, Geigy and Mooser (1955) examined

55 burrows of warthogs, originally dug by antbears (Or ctero us afer), and found eyeless tampans in eighteen of them. More Ehan l,2OO tick specimens were collected from these retreats and an additional one was taken on the body of a freshly shot warthog. They also found the burrows of other kinds of mammals infested

in Kenya.

In connection with Suan specimens from warthog burrows (Hoog. straal 1954B) (see also DISTRIBUTION IN summ above), it is of interest to note that these are from the “Nile sponge" region that becomes a vast lake during the rains. Just what the ticks do during these floods should be worthy of investigation.

Walton's (1953) records for porcupine (H strix sp.) burrows are noted above. Heisch (19543) noted nymphs adults in por. cupine burrows in Kenya and found that they had fed on porcupine blood. Geigy and Mooser (1955), also working in Kenya, did not find ticks in a porcupine burrow that they examined but a nearby hyena shelter was heavily infested.

In South Africa (Theiler, unpublished), specimens of Q. moubata have recently been taken from burrows of aardvarks or antbears,

O ctero us afer, near Stockpoort in the Potgietersrust area.
Search for ticks in the retreats of these large, almost hairless

animals will undoubtedly provide further interesting data. As noted elsewhere, other workers have found eyeless tampans in bur. rows originally dug by antbears but later occupied by warthogs.

Loveridge (1928) ambiguously associated O. moubata with gi. raffes in Tanganyika, and Santos Dias (1952H;l95§R:I95ZK) men. tioned small numbers of nymphal and adult specimens from lion, Lichtenstein's hartebeest, waterbuck, and scaley anteater. Fur. ther data for these exceptional records are desirable.

Heisch (l95OA) obtained negative results when he attempted to induce O. moubata in Kenya to bite house rats, Rattus rattus, placed in'huts for experimental purposes. Wild rodents from tick.infested Tanganyika dwellings gave no evidence of spirochetes when tested in the laboratory (Geigy an Mooser 1955).

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van den Branden and Van Hoof (1922) fed laboratory specimens on the fruit bat, Eidolon helvum.

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No other wild mammals have been reported actually to have been observed as hosts of O. moubata in nature. The fact that the burrow.inhabiting warthog-E§H_the domestic pig each serve as a host of this tick is of special interest. Heisch and Grainger (1950) have concluded that before Q. moubata became "domesticated" it inhabited large burrows of wild animals.

Roubaud (1916) conjectured that some of the several external parasites of warthog and man alike may be attracted to these hosts because of their hairless skin. This interesting theory is prob. ably not now tenable for Q. moubata in the light of present know. ledge.

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In review, it appears that large burrows of wild animals, among which those of the warthog are the most common, are the favorite and quite possibly the original habitat of O. moubata. It should be borne in mind, however, that those populations oi this tick inhabiting wild animal burrows may possibly represent a different physiological or biological race, or a distinct sub. species. It would be of value to determine the domesticability of "wild" populations.

Recently, Heisch (19540) has noted that ticks from burrows are more difficult to feed on laboratory animals than are those from domestic habitations. Geigy and Mooser (1955) observe that bush ticks are more blue gray in color, move more quickly, attach to the host and suck blood more quickly, and are hardier in cap. tivity than specimens from domestic populations of Q. moubata.

Contrary to Heisch's experience, they state that wild specimens “adapt themselves to feeding on mice and guineapigs easier than house ticks‘.

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Bedford (1934) listed several collections from South African tortoises. Theiler (unpublished) has records of nymphs and adults from four species of South African tortoises, Testudo oculifera, T. verreauii, T. schbnlandi, and Homopus femoraiis from Kimberley

and Wodehhuse Districts E from Nama.qualaE. Theiler considers tortoises to be exceptional hosts.

Rodhain (192o,1922B,c) found that blood of lizards, geckos, and snakes is easily digested by O. moubata. Although nymphs that had fed on snakes died in larger EumbEF§_than those that had fed on mammals, survivors reached the same size as mammal.fed individ. uals. Chameleon blood is initially very toxic, and digestion is slow and difficult. Though many ticks die after feeding on cha. meleons, a few do become adapted to it. Individuals that had fed exclusively on chameleons for sixteen months subsequently fed on mice when allowed to do so. Van Hoof (1924) reported similar findings. As already stated, tortoises sometimes are infested in South Africa, but no other collections from cold.blooded verte. brates in nature have been reported.

BIOLOGY

Life Cycle

Life history details have been studied and reported by Dutton and Todd (l905A), Newstead (l905A,B,C,l906A,B) and Wellman (19060, D,l907A). These were reviewed by Nuttall et al (1908). Subsequent observations were reported by Cunliffe (l92IY:_Jobling (1925), and Pierquin and Niemegeers (l953)*. Other contributions on special. ized phases are noted below. Some discrepancies in observations exist, but the broad outlines of the life cycle are well established. Critical and restrictive factors are poorly known and no observa. tions on the life cycle under natural conditions have been under. taken. The natual history of Q. moubata is gradually being elu.

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*The dates of publication of these reports will not be repeated in the life cycle section.

cidated, but each new observation suggests how many other details are yet to be known.

A summary of the life cycle is as follows: Copulation is effected by transfer of a male spermatophore to the female, after which the female indulges in a rapid blood meal and subsequently deposits a small batch of unusually large eggs in or on the soil. After the larva emerges it remains nonmotile and nonfeeding till the nymphal stage some hzurs or days later. THE active nymph, after a short rest, feeds on an available host for about half an hour, then retreats to the soil or a crevice to digest its eal. Subsequently, the nymph molts, usually four or five times, with a similar pattern of resting, feeding, and resting between each ecdysis. Sexually matue adults emerge from the last molt and normally mate shortly afterwards. The female feeds two days later and several days afterwards deposits a batch of eggs. Adult hiding and feeding habits are like those of nymphs. Seven feedings and egg batches appear to be maximum in one female's lifetime.

A minimum of about two and a half months is necessary to complete the life cycle, which normally is probably considerably more ex. tended than this. Apparently these ticks do not voluntarily wander far in search of food and considerable numbers may develop in a single building or large animal burrow.

The mating behavior of 0. moubata was described by Nuttall and Merriman (1911) but the E¢¢Tn O mechanism of insemination has been augmented by Robinson (19428). The development of the sperm has been described by Samson (1909).

In the male the spermatids travel down the vas deferens either in a continuous stream or are aggregated in rounded pellets, each containing a few hundred male elements. As stated by Robinson and Davidson (l9l4) (for Argas rsicus), it is probable that the male accessory glands secrete t e spermatophore case into which these elements pass.

Zrlccording to Robinson, the spermatophore is not chitinous. It completely dissolves in strong KOH solution at l50°C., and becomes red in Millon's reagent; therefore it is probably largely

protein.i7

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