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Figures 329 and 330, o, dorsal and ventral views.
Figures 331 and 332, o, dorsal and ventral views.

A, o genital area. B to D, o genital area, outline and profile, unengorged and unmated. E to G, spiracular plates of (E) "H. sp. no.2," (F) H. excavatum, and (G) "H. sp. no.l."

HY ALOMMA SPECIES NO. 1 NEAR EXCAVATUM Reared Egyptian Specimens

PLATE XVIIC

HY ALOMMA SPECIES NO. 1 NEAR EXCAVATUM

(Figures 331 to 334)

DISTRIBUTION

This species occurs in EGYPT and probably extends eastward and westward from here.

HOSTS

Adults feed on camels; immature stages on lizards, Acantho dactylus and Agama. In the laboratory, rabbits serve as host for all stages and man has been utilized to feed adults.

BIOLOGY

This is a fairly common tick locally on Egyptian desert lizards. Life cycle and other biological data will be presented subsequently (Hoogstraal, ms.).

REMARKS

Although probably already described, we are not yet certain which name applies to this species. The male runs to H. excava tum in the Delpy (1949A) and in the present (page 397) keys. The female superficially resembles that of H. detritum but is morphologically distinct from all others. In size, both sexes are considerably larger than H. excavatum. Adults, reared from nymphs removed from Egyptian Iizards, have produced uniform F1 adults, thus indicating the validity of this species. All specimens are remarkably similar, a phenomenon seldom seen in this genus. However, further search of field collections and additional rearing will probably reveal more variable individuals. Means to separate this species from "H. species no. 2 near excavatum" may be found on page

IDENTIFICATION

Male. The scutum measures from 3.94 mm. to 4.37 mm. in length and from 1.95 mm. to 2.90 mm. in width; specimens with a scutum measuring less than 4.10 mm. long and 2.66 mm. wide are uncommon. The scutum of H. excavatum measures from 3.52 mm. to 4.18 mm. Tong and from 2.00 mm. to 2.19 mm. wide, but seldom exceeds 3.75 mm. in length and 2.09 mm. in width.7 The appearance is that of a strong hyalomma in comparison with the typical frail guise of H. excavatum. The shiny dark brown scutum is in contrast to the Typically yellowish brown scutum of H. excavatum. Scutal puncta tions are few; minute but distinct punctations are widely scattered over the entire surface and become dense in the characteristically triangular caudal depression; large punctations number no more than those on the specimen illustrated (Figure 331) and may be even rarer. Lateral grooves are strictly confined to the posterior third of the scutum where they are deep and distinct. The caudal depression is an approximately equilateral triangle (margins curved in H. excavatum) bounded by a ridge that is not so elevated as in H. excavatum; the apex of the depression is level with the apex of the lateral grooves; the posteromedian groove is poorly devel oped and does not extend beyond the depression, the paramedian grooves are faint, rounded depressions extending as faint grooves to the middle of the third pair of festoons. The posterior margin of the scutum is bluntly rounded while that of H. excavatum is more narrowly rounded. The adanal shields are strong, broad, and quadrate posteriorly (Figure 332), and the subanal shields, that lie directly posterior of them, are larger than is usual in H. excavatum. The spiracular plate (Figure 332G) is distinguished from that of H. excavatum (Figure 332F) especially by the narrow_ ly tapered, very slightly curved tail (the tail of H. excavatum is wider and curves more abruptly apically).

Female. Scutal measurements in most specimens are approx imately 2.50 mm. in length and 2.38 mm. in width; the minimum is 1.95 mm. by 2.00 mm.; the maximum 2.71 mm. by 2.52 mm.; the outline is subcircular and the surface is smooth with very few, large, widely scattered punctations, thus being similar to that of H. detritum (the typical outline in H. detritum tapers more abruptly from the level of the eyes and is narrower posteriorly). The genital apron (Figure 334A to D) is similar to that of H.

truncatum and might easily be confused with it (cf. Figure 189A to D and page 503); its deeply depressed profile and wide outline is in strong contrast to the gradual slope and narrower outline in H. detritum and to the strongly convex profile and subcircular or more narrowly triangular outline in H. excavatum.

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Figures 333 and 334, d, dorsal and ventral views.
Figures 335 and 336, q, dorsal and ventral views.

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

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