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Figures 190 and 191, 0, dorsal and ventral views
Figures 192 and 193, , dorsal and ventral views
HY ALOMMA ABGYPTIUM
HYALOMMA AEGYPTIUM (Linne, 1758).
(Figures 190 to 193)
THE TORTOISE HY ALAMMA
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 Mediterranean 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 petshops.
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 tickinfested animals, it was found that these stages commonly attack tortoises, lizards (Agama), partridges, man, bares, 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, or 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 1938C; and Laveran 1901, Marzinowsky 1927, Popovici-Baznosano 1901, 1906,1907, and Reichenow 1910). Another parasite from this tick Coelomoplasma hyalommae, has been briefly described by Brumpt (1938D) without further classification as to group (see also Brumpt 1938E). Further studies on these parasites have not been encountered.