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work, he illustrated a cross section of the scutum (of "11. lusita.. nicum") and compared it with that of cohaerens.

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Gynandromorphs and malformed specimens of this species have been described and illustrated (as H. savi i: Pavlovsky 1940) by Pervomaisky (1950). A gynandromorpfi of excavatum (= H. savi i) has been described by FelmmMm§m~t Uampana..Rouget (1950) considers this to be an "intersexue" (see also Chabaud and Choquet 1953). An abnormal male (as H. kumari) has been illustrated by Sharif (1940). '

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The rate of growth and comparative differences among those morphological parts that are either similar or different between the two sexes of this tick have been studied by Chabaud and Cho.. quet (1953). Cuticle growth has been mentioned by Lees (1952,

as H. savigng) .

Campaniform sense organs have been briefly described (Dass\1P’¢a,l955)

Specimens from Kenya, identified as H. anatolicum, were used by Yalvao (1939) to describe features of development of the adult stage in nymphs.

DISEASE RELATIONS

MAN: The virus of Uzbekistan hemorrha ic fever has been isolated from H. excavatum (= H. anatolicum in Soviet Central Asia, where tlfis tick appears to Be at least an important natural reservoir if not a vector. Experimental work with H. excavatum (= H. turkzneniense) indicates, for the virus of Fussian sprin§..su1mner encephalitis, transmission by bite and transovarial transmission, and the same for the virus of Japa. nese (mosquito..borne) endephalitis except that transmission by biting was not obtained. These viruses, as well as that of Russian (mosquito_borne) encephalitis, persist for many months in infected ticks.

H. excavatum is commonly found infected with the rickettsiae of Q fever (Coxiella burnetii) in North Africa, southern Europe,

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and Uzbekistan. Its importance as a vector of this disease to man requires investigation.

If, as appears likely, it is true that the "H. savi i" of Soviet workers with ticks and brucellosis applies actuafy to H. excavatum, it should be noted that hereditary transmission andsubsequent infection of the host by the bite of this tick is

claimed .

The spirochetes of certain Russian relapsing fevers do not survive in this species (as anatolicum excavatum) for even a day.

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Males: Typical males are very distinctive but in almost any field collection a large number of atypical specimens may be found. Characteristically, the center of the subanal shields is posterior of the central axis of the adanal shields. This holds true for all flat, unengorged and slightly engorged indi.. viduals. Males that have not flattened after molting and before being preserved, and engorged males, especially those that have fed on large animals such as camels, almost always have the subanal shields borne on an udder_like swelling and laterally displaced as in H. dromedarii. (The subanal shields are a.l_ ways small and elongate, frequently minute or even hardly dis. tinguishable). Such specimens can be distinguished by smaller size and by the characteristic strong depression of the posterior part of the scutum between two smooth lateral ridges; this de_ pression is almost always densely punctate. (Some atypical H. dromedarii tend towards a resemblance of this last cheracterj. The lateral grooves are very short, restricted to the posterior third of the scutum. A line of punctations frequently continues anteriorly from the lateral grooves; these may be goove_1ike enough to confuse keying the specimen. The scutum, away‘ from

the depressed caudal area, has rare, widely scattered, medium..size punctations, or none, but atypical very small and superficial punctations may rarely confuse this pattern. A pale parma is frequently present; the festoons are greatly variable in distinctness. The scutum is usually strongly convex, and all specimens are definitely small in size for H alomma ticks (scutal length no more than 4.18

mm. , rarely over 3. mm.; width no more than 2.19 mm., rarely more than 2.19 mm.). Certain populations that key to H. excavatum but

measure above the upper level of this range represent dIstin' ct species of uncertain identity (see pages 880 to 886).

Females: The knob-like genital apron is more or less (but always definitely) bulging in profile; it may be circular, elongate... ly triangular, or widely triangular (but if so always distinctly nnich smaller than in H. mar inatum or similar species) in outline; the circular outline is mos? cfiaracteristic and distinctive; the elongately triangular outline is fairly common and usually fairly distinctive; the widely triangular outline is not common but is apt to be confusing. The scutum is extremely variable in color and in length.width ratio, but it has very few large punctations scattered in the central field, a few more in the scapular areas, and sometimes some to many very fine, superficial punctations over much of its surface. The scutal surface of engorged specimens frequently becomes extremely rugose. Typical engorged females are comparative. ly small and narrowly elongate but quite thick dorsoventrally thus presenting a narrowly rectangular appearance.

The larva and n'm h (as H. savi i) have been described and compared witfi those of other species % Bernadskaia (193%) and

by Feldman..Muhsa.m (191.8) .

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Figures 170 and 171, d‘, dorsal and ventral views
Figures 172 and 173, Q, dorsal and ventral views

A, 9 genital area. B to D, 9 genital area, outline and profile. A and B, unengorged. C, partly engorged. D, fully engorged.

I-UALCMMA IMPELTATUM
Egyptian Spec lme'ns

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NUTE: The name im ltatum, proposed by Schulze and Schlottke (1930) in a brief key to H alomma ticks, was said to apply to a subspecies of savi ' . u sequent workers were unable to recognize this tick on ¥he basis of the brief data provided. The original materiafl. was redescribed and illustrated Kratz (1940). Kratz also indicated that Tonelli..Rondelli's (19320 H. exrzyfihraelm from Eritrea is probably a synonym. Delpy overlooked-bo .

ezythraemm and Kratz's description of im ltatum and (1946A')' escri ll. brum ti as a. new species from Cameroons. It now appears that H. Brum ti is a synonym of H. imp_e_ltatum. The fifiae

status of H. E um is still moot.

DISTRIBUTION IN THE SUDAN

In the Sudan, im ltatum is restricted to the drier central Provinces. It may occur locally in Northern Province, but no records are available.

Kassala: Kassala and Sinkat (cattle; SVS). Port Sudan (donkeys E cattle; SVS).

Kordofan: El Obeid and Umm Inderaba (cattle; SVS). “Northern Kordofan' (camels; SVS). See also Khartoum below.

Darfur: Sibdo (horses; SVS). Muhagariya (camels, cattle, horses, and donkeys; SVS). See also Khartoum below.

Khartoum: A large number of specimens taken from cattle from ordofan a.nd Darfur Provinces at the Khartoum Quarantine Station, where they were enroute to Egypt (I-IH)_:_7

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