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Genital apron circular or a less narrow-
ly pointed triangle with lateral margins
approximating dorsal margin in length.
Scutum usually somewhat longer than wide;
punctations variable; usually less rugose.
Size moderate (except H. schulzei) to
small...

8. Genital apron a triangle bounded on each
side by a lobe; greatly bulging in pro-
file. Scutum usually with sinuous pos
terior margin, numerous small puncta
tions, and two irregular, submedian
rows of large, deep punctations. Usual
ly moderate size..

Genital apron circular or triangular
but lacking lateral lobes; greatly
bulging or gradually depressed in
profile. Scutum usually with very
few punctations..

9. Genital apron triangular; gradually depressed except when greatly en gorged but never convex in profile. Scutum smooth and shiny with very few, scattered punctations of large size; uncommonly with superficial small punctations. Usually moderate size..

Genital apron small, triangular or
circular, convex or bulging in pro
file. Scutum usually lacking smooth,
shiny appearance of H. detritum; few,
scattered punctations, those present
small or moderate size; almost never
large. Usually small size and narrow
shape...

..8

.H. IMPELTATUM Figures 172 and 173

9

..H. DETRITUM

Figures 160 and 161

.H. EXCAVATUM Figures 168 and 169

[blocks in formation]
[graphic][subsumed][subsumed][subsumed][subsumed][subsumed]

Figures 190 and 191, d, dorsal and ventral views
Figures 192 and 193, o, dorsal and ventral views

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

HY ALOMMA AEGYPTIUM

Specimens from Land Tortoise, Eastern Anatolia Hoogstraal Collection

PLATE LV

513

HYALOMMA AEGYPTIUM (Linne, 1758).

(Figures 190 to 193)

THE TORTOISE HYALOMMA

The much mooted name H. aegyptium has been frequently used as a "catchall" by workers in many countries for a number of spe cies. Consequently much literature referring to Hyalomma ticks has been hopelessly confused, even to the present day.

King (1926) lumped all Sudan species under the name H. aegyptium*, as did most other workers on African and Near Eastern ticks of his time. H. aegyptium (Linne, 1758) is now recognized as a distinct parasite of tortoises in the Mediterranean area and Near East. In Russia it is confined to Crimea, Georgia, Armenia, the Caucasus, Azerbaijan, Turkmen, Uzbek, and Tadzhik (Pomerantzev 1950). It is common in many parts of Asia Minor (Hoogstraal, ms. and occurs in Afghanistan (Anastos 1954).

.)

The tortoise hyalomma does not occur in the Sudan, elsewhere in tropical or southern Africa, or in Europe away from the Medi terranean and Black Sea areas. Although originally described from Egypt, where tortoises are said to have been numerous on the Medi terranean littoral, H. aegyptium apparently is now extinct here. In present-day Egypt, tortoises occur only a few miles east of the Libyan border - extremely rarely as far as seventy miles east of Libya and in Sinai a few miles west of Palestine. No ticks have been found on recent Egyptian tortoises, except on specimens from Palestine in Cairo pet-shops.

Tortoises are the hosts of predilection of adult H. aegyptium. Exceptionally, lizards, hares, and hedgehogs are attacked. While other mammals may be infested rarely, long lists of various hosts for this tick are all erroneous, based as they are on old records in which all species were lumped under the name H. aegyptium. In

*With reference to reports of "H. aegyptium" from the Sudan, it should be noted that the actual tick species with which O'Farrell (1913A,B), did his interesting work on an entomogenus trypanosome, Crithidia (?Herpetomonas) hyalommae, cannot now be determined.

Anatolia, however, when rearing larvae and nymphs from tick-infested animals, it was found that these stages commonly attack tortoises, lizards (Agama), partridges, man, hares, hedgehogs, and a wide variety of rodents (Hoogstraal, ms.). A number of Russian host records were presented by Olenev (1928B).

The life cycle of "H. aegyptium" described by Nuttall (1915) applies to H. marginatum. Nuttall's lot 1305a in British Museum (Natural History) was used for this study. No material for his lot X (from Rome) can now be located. It appears that the study of the external morphology of each stage and of the bionomics of "H. aegyptium" in India (Sharif 1924) applies actually to H. excavatum, but this is not certain.

A popular article concerning the actual H. aegyptium has recently appeared in the Illustrated London News (Browning 1950). Based on living ticks arriving in the British Isles on pet-shop tortoises from southern Europe, this account should interest persons who frequently encounter this name promiscuously used in the literature. Distribution data in the Browning paper are from literature references under H. aegyptium, and, therefore, far more extensive than the actual geographic range of this species in nature.

Contemporary published reports on disease transmission by ticks unfortunately continue to perpetuate the early confusion In identification of species in this genus. The tortoise para site, H. aegyptium, has never been incriminated as a vector or reservoir of pathogenic organisms of man, other mammals, birds.

H. aegyptium does, however, transmit two sporozoa to land tortoises in northwestern Africa and in the Near East. These are Haemogragarina mauritanica and H. stepanovi (cf. Sergent and Sergent 1904, Laveran and Negre 1905, Nicolle and Comte 1905, Laveran and Pettit 1910, Brumpt 19380; and Laveran 1901, Marzinowsky 1927, Popovici-Baznos ano 1901,1906,1907, and Reichenow 1910). Another parasite from this tick Coelomoplasma hyalommae, has been briefly described by Brumpt (19380) without further classification as to group (see also Brumpt 1938E). Further studies on these parasites have not been encountered.

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