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of adults, and a variety of small mammals are occasionally infested.

Immature stages feed on a large variety of birds and also on hares.

Adults

Domestic animals: See two paragraphs above.

Man: Howard (1908). Bedford (1932B). J. B. Walker (correspondence; Q tick from Tanganyika).

Wild animals: Rhinoceros (Two collections in BMNH from

Kenya). Buffalo (Santos Dias 1952D,1953B. Onderstepoort collection from Northern Rhodesia. BMNH collection from Kenya, Sudan records above). Eland (Schulze 1936A. Two collections in BMNH from Southwest Africa. HH collection from Tanganyika. Onderstepoort collection from South Africa and Tanganyika). Bushbuck (MCZ collection from Tanganyika). Duiker (Sylvicapr

immi) (Bedford 1932B). Sable antelope (Santos #####© # (Onderstepoort collection from Southwest Africa). Giraffe (Santos Dias 1952D,1953B. Onderstepoort collection from northern Kenya and Southwest Africa. Sudan records above). Jackal (Canis mesomelas schmidti) (Stella 1939B). Zebra (Santos Dias 1952D. THMNH collection from Tanganyika). Hare (Howard 1908. Onderstepoort collection from South Africa).

"Fowls" (Howard 1908). Ostrich (Howard 1908. Bedford 1932B. d' in HH collection, from "west of Afmadu", Somalia, 1952, Col. D. Davis legit). Guinea fowl (Santos Dias 1953B).

Adults from the following birds are present in the Onderstepoort collection (Theiler, £ ostrich (Southwest Africa), swallow (Southern Rhodesia), Cape dikkop (Burhinops c. capensis from South Africa), and mocking chat (Thamnolaea c. cinnamomeiventris from South Africa).

Immature Stages Hosts of the immature stages noted by Bedford (1932B, 1936) are not listed here since it is questionable that larvae and nymphs of H. rufipes and of H. truncatum (= H. transiens) could be differenti # at that time. Nymphs have been reported from a hare (Alexander, Mason, and Neitz 1939), and from a kite (Sudan records above); the former workers induced five of the twelve nymphs to reattach to a guinea pig.

Kratz (1940) records the finding of a nymph, which molted into a male rufipes, on a female comorant caught on the high seas between the # trip of Madagascar and the Comores Archipelago.

The Onderstepoort collection (Theiler, correspondence) has larvae (L) and/or nymphs (N) from the following South African birds;

Namaqua thrush, Afrocichla smithi
Cape thrush, Afrocichla o. olivacea (2 collections)

White-throated seed-eater, Crithagra a. albogularis
Mocking chat, Thamnolaea c. cinnamomeiventris # collections)
Red-winged starling, drus m. morio

Starling (Southwest £ -
Boubou shrike, Lanjarius f. ferrugineus

Gray tit, Parus afer

Fiscal flycatcher, Sigelus silens
Cape barn owl, Tyto # affinis"

The same collection contains nymphs from a hare and a rock hare (Pronolagus randensis) in South Africa and from a hare in Uganda.

In Egypt, nymphs (reared to adults in the laboratory) have been found only on birds (Hoogstraal, ms.) although adults are locally common on domestic animals. The hosts have been:

Wheatear (European form), Oenanthe 2. oenanthe
Blackeared wheatear (Eastern form) , Oenanthe hispanica melanoleuca

The former bird breeds throughout most of Europe east to Central and northern Asia and to northern Alaska; it winters in Arabia and tropical Africa, also in Asia to India. The latter "breeds in the Crimea, Bulgaria, and almost throughout the Balkan peninsula, Asia Minor, Palestine, and western Persia, etc.; winters in Egypt and Sinai to the Sudan, Ethiopia, the Red Sea coast, and has straggled

to the southern Sahara, British Islands, Malta, and northwest Africa" (Meinertzagen 1930). Possibilities for the wide dispersal of this tick are easily recognized.

BIOLOGY Life Cycle Under laboratory conditions, H. rufipes is a two host tick although it possibly may also undergo a #. host type of life

cycle. Theiler (1943B and 1955 correspondence) has summarized the developmental stages as follows:

PERIOD DAYS
(1943B) (1955)
Preoviposition 4 to 12 4 to l9
Oviposition period 37 to 59
Oviposition to hatching 34 to 66 28 to 66
Larval prefeeding period ?
Larva feeds 5 to 7
Premolting period 2 to 15
Nymphal prefeeding period ?
Nymph feeds 7 to 10
Premolting period l, to 95
(Larvae and nymphs on host) 13 to 45 average 14
Adult prefeeding period ?
Adult (female) feeds 5 to 6 5 to 12

It appears that the minimum time for completing the life cycle is between four and five months but double this period may be required under local conditions.

"The life cycle of H. aegyptium (= ?H. rufipes, possibly mixed with H. truncatum: HH) is of particular value in that it illustrates the influence of vermin in the distribution of the species. On sheep, cattle, and domestic fowl it behaves as a three host tick, requiring a separate host for the larval, nymphal, and adult stages. On the hare, H. aegyptium will feed as a larva, become engorged, molt as a nymph # leaving the host, feed as a

nymph on the same individual host, and then drop off the host for molting. Thus on the hare the life cycle requires only two hosts" (Brassey-Edwards 1932). This interesting phenomenon should be reinvestigated.

The long oviposition period is especially noteworthy. Unfed larvae may survive a year, unfed nymphs three months, and unfed adults for longer than a year (Theiler 1943B). Enigk (1953) observed unfed adults surviving up to two years.

Howard (1908) considered H. rufipes as a two-host tick with one generation a year in South Africa. He described, illustrated, and discussed the immature stages but did not differentiate them from those of H. truncatum which he apparently did not rear. Jack (1928) noted a two-host and a three-host type of life cycle for this tick.

Ecology

Thorburn (1952) states that on cattle the chief site of infestation of this tick is in the tail region. Specimens in the present collection are from the flanks, genitalia, udders, and perianal regions. The anal area is mentioned by Matthysse (1954). Nymphs are always, in our experience, on the crown of the head of their avian hosts.

du Toit and Monnig (1942) record the finding of a male attached to the hard palate of the mouth of a cow, and indicated that on the farm where this occurred this phenomenon had been observed on several occasions.

H. rufipes ranges through the more arid areas of tropical and southern Africa but only localized populations maintain themselves in the severely arid conditions of northern Africa. It exists where annual rainfall is from ten to thirty inches a year. It may also thrive in irrigated areas with diminished rainfall or where a long, severe dry season occurs between an annual rainy season of approximately forty inches. In the Sudan, it is more common in the drier savannah and semiarid central areas than in the southern forest and savannah areas; it occurs in the Nile Valley, but is not known in extreme desert conditions. In Egypt,

H. rufipes is found only in the Nile Valley, never in extreme desert areas.

The hairy hyalomma is included in Wilson's (1953) Amblyomma eme - R. Pravus (= R. neavi) association (see page ITFIEF # found in areas where rainfall rarely exceeds 25 inches annually.

The only ecological survey of this tick is that of Theiler (1956) who lists the areas of its occurrence and absence in southern Africa. It occurs in all desert and semidesert areas with rainfall up to thirty inches annually, but at higher altitudes or in semitropical conditions, 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. rufipes ranges from hot deserts into areas with up to 120 days of frost annually. 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 forested areas of central Africa. In many regions it is active the year around, but in others more so in summer than in winter.

In Russia, H. rufipes has been reported (as H. impressum) from the western deserts of Transcaucasia (Pomerantzev, Matikashvily, 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.

CATTLE: H. rufipes causes abscesses and sloughing of the host skin. These areas often serve as points of penetration of the screwworm # bezziana Villem. This tick may also be associated with footrot of sheep, a secondary infection by

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