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The sorting out of these host records awaits a thorough biological and taxonomic study on this interesting group of ticks.

BIOLOGY
(See also REMARKS below)

Life Cycle

Lounsbury (1905*) stated that adults will not feed on goats or on oxen if they have not first fed from a tortoise in an earlier stage. Adults attached to the host before seeking the other sex, unlike many other species of Amblyomma. Lounsbury also provided observations on time required # each stage and for feeding. These data are not abstracted here for in the light of confused nomenclature it is questionable whether the species with which Lounsbury worked is the same as that in the Sudan. Note that Alexander (1931) was unable to induce South African adults of A. marmoreum to feed on cattle.

Scology

In the Ethiopian Faunal Region, this group of ticks occurs in a variety of faunal areas. Where tortoises are common these ticks are often abundant, but this incidence is by no means universal in Africa.

On tortoises, these ticks are usually deep in the host's axillae and it is necessary to kill or anesthetize the animal to see or secure all of the specimens.

DISEASE RELATIONS

Textbook Statements that A. marmoreum actually has been incriminated as a vector of boutonneuse fever of man refer merely to a remark that this was one of several tick species found on patients.

*See Robinson (1926).

Experimental attempts to transmit heartwater (Rickettsia ruminantium) of cattle through this species have failed.

REMARKS

A. marmoreum is considered by most workers to parasitize chiefly the rhinoceros and tortoise but Theiler (correspondence) has found so much variation in morphology and host data on specimens sent from various parts of Africa that she prefers to refer to all specimens as "A. marmoreum group" until they can receive more intensive study. Most of her specimens come from tortoises, a few from Waranus lizards and cattle. She considers the rhinoceros to be an accidental host, or else the host of a separate, as yet unrecognized, species or subspecies. She has large numbers of nymphs of this group from fowls.

Schulze (1932A) realized the complexity of the marmoreum group and proposed new names for specimens from various parts of Africa. Reasons for these differentiations appear quite invalid.

A definitive species name for Sudan material awaits assignment. The range of variation in even the rather small series of Sudan specimens at hand casts considerable doubt on the validity of all those "related species" that are based on certain aspects of scutal ornamentation or on coxal spur characters.

The structure of the larval eye and its sense organs in specimens of the A. marmoreum group has been described and illustrated

by Gossel (1935). Nuttall (1914A) reported on a malformed specimen of A. mar

moreum, from the Sudan, and Schulze (1941) noted characteristics of the haller's organ of this species.

IDENTIFICATION
Males: Large, at least 6.0 mm. x 5.0 mm. Scutum with

reddish-yellow ornamentation that is variable but essentially as illustrated; pale areas in this species are more separated

from each other by dark stripes than they are in A. muttalli; festoons bicolored; punctations consisting of few, scattered large and numerous small; lateral grooves deep and long; eyes flat.

Females: Large, from 7.0 mm. to 30.0 mm. long and from 6.0 mm. to 20.0 mm. wide, depending on degree of engorgement. Scutum extensively pale ornamented and with central pale area broadly rounded posteriorly; large punctations scattered over surface including from five to twelve on posterior half; eyes flat.

Although the scutal length of A. marmoreum group typically equals its width or is slightly greater than the width, the Sudan specimen illustrated (Figure 74) is exceptional in that its width is considerably greater than length.

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AMBLYOMMA NUTTALLI Dönitz, 1909.

(Figures 76 to 79)
THE SMALL REPTILE-AMBLYOMMA

L N 9 d. EQUATORIA PROVINCE RECORDS

Reptiles 7 Farajok Kinixys b. belliana Mar l 3 Torit ni:'s E. belliana Aug 3 Meridi, 50 mi. northeast of Kinixys b. belliana Oct (SVS) l TOTit, £ānūš Il- niloticus Dec l TOrit Varanus e. exanthematicus Jan Mamal l TOrit Ourebia ourebi aequatoria Feb Bird l TOrit Francolinus clappertoni

Eedgif Jan

These specimens indicate the presence of A. nuttalli on both the east and west banks of the Nile in Equatoria Province.

Sudan Government collections contain specimens only from Ossa River (H. H. King legit, 1913), now a part of Uganda. King (1926) mentioned no Sudan locality records for this species. DISTRIBUTION IN THE SUDAN Kordofan. As A. werneri (Schulze 1932A), a single specimen

from Talodi." The host is most probably the "Cinixys belliana." mentioned by Werner (1924).

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