Certain unusual morphological characters of this easily recognized species cause the tortoise hyalomma to be considered in a separate subgenus, Hyalommasta Schulze, 1930.

H. aegyptium punctata Schulze, 1919 (see also Kratz 1940), name proposed for a single specimen from Malta and subsequently overlooked by even Schulze himself, is undoubtedly a synonym of H. aegyptium.

Pomerantzev (1950) considers Dermacentor rosmari Ass (1935), described from nymphs from walrus in the Kara (White) Sea and said to be the northernmost ticks on record, as a synonym of H. aegyptium. On the basis of the original description and illus trations of D. rosmari, its systematic position is uncertain but this synonymy is hardly convincing.

The synonymous name H. syriacum Koch, 1844, has frequently been used for the actual H. aegyptium. So far as has been determined, H. syriacum has been confused with no other species.

Both sexes can be readily distinguished from key characters provided herein.

A, Q, genital area. B and C, Q, genital area,
outline and profile, unengorged.

HY ALOMMA ALBIPARMATUM

Specimens from cattle, Kenya; from Nuttall lot 3773, exchange, British Museum (Natural History). Hoogstraal collection.

PLATE LVI

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HY ALOMMA ALBIPARMATUM Schulze and Schlottke, 1930

(= H. BRUNNEIPARMATUM S. and S., 1930).

(Figures 194 to 197)

THE PARMATED AFRICAN HYALOMMA

H. albiparmatum, presently known only from Kenya, Tanganyika, and Togo, is similar to H. truncatum except that the central fes toon is differentiated as a parma in the form of a celluloidlike cover of variable size, shape, and color. No constant characters have been discovered for differentiating females of these two species.

Delpy (1949B) considered H. impressum albiparmatum Schulze and Schlottke, 1930, from East Africa, as a synonym of H. marginatum (= H. savignyi) or questionably of H. truncatum (H. transiens); he considered H. brunneiparmatum of Schulze and Schlottke (1930) to be a synonym of H. marginatum (= H. savignyi).

Feldman Muhsam (1954) stated, after examining Kenya laboratoryreared material of H. albiparmatum submitted by J. B. Walker that H. albiparmatum is a synonym of H. truncatum. Dr. Theiler and the writer, after examination of the same material, are convinced that Walker's H. albiparmatum is a distinct genetic entity worthy of full species rank. It is also apparent from Walker's material and from other series in British Museum (Natural History) collections that H. impressum brunneiparmatum Schulze and Schlottke, 1930, from Togo is a synonym of H. albiparmatum and not of H. truncatum as stated by Feldman Muhsam 1954. Miss Walker is preparing a report on this species for publication in Parasitology. Hosts of the parmated African hyalomma appear to be the same as those of H. truncatum.

British Museum (Natural History) collections contain material from cattle and from a rhinoceros from Zatta Plains, Kajiado, Namanga, and the Masai Reserve, Kenya (HH det.). J. B. Walker (correspondence) has seen specimens from a rhinoceros from Iringa District, Tanganyika, and from a warthog in Chunya District, Tanganyika.

Figures 198 and 199, o, dorsal and ventral views
Figures 200 and 201, o, dorsal and ventral views

A, Q, genital area. B to E, Q, genital apron, outline and profile; all unengorged; E dried, contracted specimen.

HY ALOMMA HUSSAINI

PLATE LVII

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HY ALOMMA HUSSAINI Sharif, 1928.

(Figures 198 to 201)

HUSSAIN'S INDIAN HY ALOMMA

AND REMARKS ON THE SUBGENUS HYALOMMINA

Special note should be made of the subgenus Hyalommina, es tablished by Schulze (1919) for the new species H. rhipicephaloides from the Red Sea area. Subsequently, Schulze (1936) placed H. lewisi from Tanganyika (and Kenya) in this subgenus and Sharif 71928 and 1936) included H. kumari and H. hussaini from India. These are discussed below.

The criterion proposed by Schulze for this subgenus is the absence of subanal shields.

With regard to the so-called "H. rhipicephaloides", it has been our experience during field collecting and study of Hyalomma material from the Near East, Asia Minor, Arabia, North Africa, and tropical Africa, that weak, poorly developed, apparently undernourished, runts of any Hyalomma species frequently lack subanal shields. Such individuals may be part of a series in which some are typical of a common species (such as H. excavatum and others, usually smaller and weaker, conform to the same spe cies in morphological characters, except that they lack subanal shields. It has also been noted from personal field experience and from series in British Museum (Natural History) collections, especially those of the late Professor Buxton from Iraq and Palestine, that when nymphs are removed from a bird, lizard, or small mammal and placed in a vial to molt, the resultant adults, obviously affected by abnormal, artificial conditions, are frequently frail and lack subanal shields. This feature is the rule rather than the exception among adults reared from nymphs that have become overgrown by the host skin (see below and page 447).

Schulze (1932C) referred to "Hyalomma (Hyalommina) rhipicephaloides" as a "half endoparasite (and compared it with