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H. rufi s is found only in the Nile Valley never in extreme 'dese'17‘E areas . ,

The hairy hyalomma is included in Wilson's (1953) Ambl omma nmn - pravus (: R. neavi) association (see page ), which s ound in areas where raififall rarely exceeds 25 inches annually.

The only cological survey of this tick is that of Theiler (1956) who lists the areas of its occurrence and absence in south. ern Africa. It occurs in all desert and semidesert areas with rainfall up to thirty inches annually, but at higher altitues or in semitropical coditions, where the relative humidity is higher, it is absent even though annual rainfall is little or no greater than in some of the hotter, drier areas. It does not occur in winter rainfall areas, where rain falls throughout the year, or in coastal areas with high relative humidity as a result of proximity to the sea. Temperature appears to be a limiting factor of lesser importance since H. rufi s ranges from hot deserts into areas with up to l20'days of Irost annual. ly. Increase in temperature associated with increase in relative humidity restricts the tick's range. Other factors being equal, the hairy hyalomma occurs in most vegetational types except for. ested areas of central Africa. In many regions it is active the year around, but in others nnre so in summer than in winter.

In Russia, H. rufi s has been reported (as_H. im essum) from the western deserts of Transcaucasia (Pomerantzev, Eatikash. vily, and Lototsky 1940) and, in western Tadzhikistan, from

mountain pastures but not in the valleys (as H. aequipunctatum) (Galuzo and Bespalov 1935).

DISEASE RELATIONS

MAN: Nymphs infected with boutonneuse fever (Rickettsia conorii) have been taken from a hare in South Africa.

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CATTLE: H. rufipes causes abscesses and sloughing of the host skin. These areas often serve as points of penetration of the screwworm C somia bezziana Villem. This tick may also be associated wit ootrot of shes , a secondary infection by

bacteria, and lesions from its bites may also lead to lameness in sheep. The possibility that the hairy tick may be a vector of sweating sickness (virus) of cattle has been mentioned.

IDENTIFICATION

Male: H. rufi es, almost without exception, is a large, robust, shiny black tick with a comparatively broad body outline. Its scutum is densely and rather uniformly punctate, so much so that the lateral grooves are obscued. The punctations are close together and while they give the impression of being rather uni. form, they usually grade imperceptibly from large posteriorly to smaller anteriorly. There is little differentiation of the caudal area. Ventrally, the subanal shields are directly pos_. terior of the adanals and the circumspiracular area is more or less hirsute, but a fair to dense accumulation of hairs always occursin this area. The ventral integumnt is usually somewhat more hirsute than in other species. The legs are reddish brown with bright, paler rings. The posterior body margin is typically broadly rounded but not infrequently may be somewhat constricted and thus tend to approach the form of that in H. im ressum. New. ly molted specimens are reddish brown and rare-preserved Individ_ uals show this color. The body shape of some specimens is more narrowly elongate than is typical for this species, but such individuals always appear to be rather weak and poorly nourished.

Females: This sex often reaches considerable size. Cir. cumspiracular pilosity and color are like those of the male; scutal punctations are like those of the anterior part of the male scutum. The genital apron is a wide shield that bulges strongly from a deep anterior and posterior indentation. The outline of the apron is much like that of H. mar inatum and H. im ressum; however the division of the apr3n of the Iatter spa. cies into an anterior ridge and a posterior button readily separates this from H. rufipes.

The larva has been sketched by Bedford (1934) and Theiler (1943B)

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Figures 186 and 187, d‘, dorsal and ventral views
Figures 188 and 189, Q, dorsal and ventral views

A, Q, genital area. B to D, Q, genital area outline and profile. B, unengorged. C, partly engorged. D , fully engorged.

HYALQIIMA TRUICATUM
Ear: SpecImens

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HYALOMMA TRUNCATUM Koch, 1844.
(Figures 186 to 189)
THE AFRICAN manna

NOTE: The Nuttall school referred to H. truncatum as ae tium. During the past five years, most aut rs ave called thés species H. transiens the authority for which has been at. tributed to Schulze (I9I9) or to Delpy (1946A). Feldman-Muhsam's (1954) studies of Koch's type specimens leave no doubt that this species is Koch's (1844) H. truncatum. Feldman-Muhsam (op. cit.) has also compared the type specimens of several of Schu1ze's African "species" and found them to be identical with H. truncatum. These are noted below in the distribution section.

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L N 9 d‘ EQUATORIA PROVINCE RIIJGRDS

1 Lugurren Phacochoerus aethiopicus bufo Jan

1 Torit § scrofa sennaarensis Mar 1 1 Kajo Kaji Foams caffer aequinoctialis - (SVS) 1 1 Kapoeta omes 1c cattle Jul (SVS) 1 l Torit domestic cattle Jul

1 5 9 Torit domestic cattle Dec (2)

1 Lalanga domestic cattle Dec SVS)
2 2 Iliu domestic cattle Dec
12 1. Tombe domestic cattle Jan (svs)
4 8 Kapoeta domestic cattle Dec

2 Loronyo domestic goats Jan

2 Torit domestic goats Jan

Tortoise

1 1 Juba Kiniltys belliana Dec

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DISTRIBUTION IN THE SUDAN

The following material has been studied:

Ba.hr F3. Ghazal: Galual.Nyang Forest (Large numbers of adults from several gira71'fes in March, May, and J1me; SVS. Moderate num. bers of adults from forest buffalos from February through April; SVS, HH. Small numbers of adults from tiang, roan antelope, domestic horse, and on ground from February to April; SVS, HH). Fanjak (Small numbers of adults from cattle, February and March; SVS, HH). Wau (roan antelope; SGC). Yirol (cattle; SVS).

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Note: The following records consist of one to ten adult specimens per collection unless otherwise mentioned.

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Blue Nile: Lake Ras Amer (camel; SGC). Hassa I-Ieissa (camel; G. Kohls det., G. B. Thompson, correspondence). Wad Medani (cattle and camels; HH).

Darfur: Nyala (camel; SVS). Muhagariya (horses, donkeys, cattle, E camels; SVS). Zalingei (camels, cattle, horses, donkeys, and goats; SVS). Kulme (no host record; BMNH). Radom (cattle; SVS).

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Z‘ Khartoum: Apparently not established in this Province but arrives in' fairly large numbers on Kordofan and Darfur cattle for export to foreign markets;

Kassala: Kassala (goats; SVS). See EGYPT below.

Northern; Rare in this Province but arrives at the Wadi Halfa Quarantine on cattle en route to Egypt. Known only from report by Chodziesner (1924) from Delgo.

DISTRIBUTION

£1. truncatum is the sole endemic representative of this

genus that is widely spread throughout the Ethiopian Faunal

Region (Figure l) and nowhere else. It commonly occurs in the drier parts of this Region but appears to increase in numbers

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