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or (CNPM) for Chicago Natural History Museum collections. Since King's (1926) review, only two literature references for ticks from definite localities in Equatoria Province have been published and these have been noted, following the month of collection, in the

usual literature reference manner.

Most Equatoria Province collecting localities may be located in Figue 317. Common names of hosts may be found in Chapter V. The situation of a few of King's early collecting localities can. not now be definitely ascertained, but they are all close to the

present Uganda border.

Reasons for special reference to Equatoria Province are several.

My Sudan collection is largely from this Province, and it is from hee that most of the new data presented in this report have been obtained. Also, Equatoria Province represents the northern limits of a nuber of truly tropical African species. Of these, a few um. doubtedly range into Bahr El Ghazal and Upper Nile Provinces,

though they are not yet recorded from these areas.

Ticks now known from the Sudan number 62 identifiable species plus two additional subspecies. Of this total of 64 identifiable forms, 52 occu in Equatoria Province. Twenty_five are presently recorded only from Equatoria Province and five are known only from Bahr El Ghazal Province. Two uncertain forms are also listed.

DISTRIBUTION IN TH SUDAN

Under DISTRIBUTION IN SUDAN all known collecting localities have been listed for each species by Province, with the exception of course, of Equatoria Province, which is separately considered. Besides my own collections, the chief source of this information has been the collections of the Sudan Government, for which H. H. King, R. Cottam, W. Ruttledge, D. J. Lewis, and a few other persons have been largely responsible.

Specimens submitted to me for identification by the Sudan Veterinary Service have been important for data on species parasitizing domestic animals. British.Museu (Natural History) collections have contributed additional information for areas outside of Equatoria Province. Almost no other Sudan data have appeared in literature,

except for a few papers by King, one or two by Ruttledge, and brief notes by Balfour and a few other persons.

DISTRIBUTION

Under the heading, DISTRIBUTION, all available pertinent literature records for each political territory of Africa have been listed. I have attempted to select critically each reference for accuracy of species identification and to include only references based on actually known specimens in relation to distribution, disease, control, biology, availability for taxonomic study, etc. Authoritative taxonomists' lists have been included especially where localities are involved and where questions of species iden. tity in any territory exist. Also noted are references by experi_ mental workers who have indicated the source of their material; biological variations within populations presently considered as identical species my subsequently prove to be of the utmost im. portance in evaluating results of laboratory experiments.

While I personally am concerned with these data in the inter. ests of geomedical knowledge, it is intended that these lists should be a useful guide to interested persons in the territories concerned. Otherwise, this listing is chiefly for advanced, specialized stu_ dents with some knowledge of the literature, who should be able, by consulting the reference titles in the bibliography, to locate subjects of interest. After serious consideration, it is felt that further breakdown of these references into subject groups would be too unwieldy and cumbersome.

Maps showing tick distribution in Africa will be presented in subsequent volumes of this work.

Every attempt has been made to provide as complete a list of

useful references as possible. Probably, all really important works have been seen and noted but if any has been missed it will be much appreciated if readers will call my attention to it.

HOSTS

The object of the HOSTS section has been to indicate the chief references to kinds of animals on which each species feed in each life stage and to give a brief statement concerning the preferred host or hosts. The references following each host do not necessarily include all reports in which the animal has been mentioned. Further

pertinent host suveys may be included in the section entitled BIOIOGY, of which the host list should, of course, be considered an integral part. The common name of non_Sudanese hosts may be found in Allen's (1939) checklist of African mammals. After serious consideration of several suggestions that the scientific name of each kind of host be provided, it has been decided to do so only where the common name

might frequently be confused, as for the "wild dog‘ or “hunting dog",

Eycaon pictus.

BIOLOGY

All available references, including data on BIOLOGY of species discussed herein, have been summarized in more or less detail, depening on the weight of their importance. It is hoped that this section will be especially useful in indicating futher research problems.

DISEASE REIATIONS

DISEASE REIATIONS with which each species has been incriminated are usually nerely listed by common name and etiologic agent. This section is intended only as a cross reference to sub'ect cha ers n the subse uen vo ume on'dIsease relations. Uhpu 13 e res s of_ Fork Ehdertaken in the-viroIogy ahd_EEEtErie1egy laboratories of NAMRU3 on Sudan ticks are also included in this section.

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RMARKS

Miscellaneous REMARKS are included here. This section preceeds that on identification if most of the notes are taxonomic or else follows that on biology if mostly other subjects are involved.

IDENTIFICATION

Diagnostic criteria in addition to key characters are provided for IDENTIFICATION by the average reader. Where Sudan material or special studies uodify previously accepted diagnostic features or are of other importance, greater detail is provided. Otherwise, no attempt has been made to present a full description of each species

since this falls in the province of mre complete, overall taxonomic studies. For serious studies, specimens rather than written descrip.

tions are almost invariably required.

A word of explanation is due concerning the absence of species diagnosis for immature stages of ticks treated in this report. Often, when collections are mde from hosts of smller size, the only ticks on them are imnnture and the difficulty or impossibility of identifying them is most discouraging. ‘Larvae and nymphs of about half the Sudan tick species have been described, but those of even fewer spe. cies can be distinguished from all others with any degree of confidence. The inclusion of what we do know would be of little practical value, except to a very few most highly specialized students. Any. one favorably situated in this area with resources for rearing pro.

geny from known, isolated female ticks can mks valuable contribu. tions in this respect. At the present time, Dr. Theiler mad I are

gathering data on this subject which will be published as soon as we have sufficient informtion to make a utilitarian report.

In morphological terminology, I have followed alnnst entirely the usage of Cooley (191.6) a.nd Cooley and Kohls (1941,), except that I have substituted the word "segment" for "article" as used by these authors. Where Kohls has recently modified some designations, I have followed his lead. Cooley and Kohls‘ terms have not been ex. tensive enough for adequate description of Rhi ice halus species, and I have been forced to add to them. Unfortunately, some termi. nolog used by British, American, and other workers differs or con. flicts. An International Committee needs be called to decide a staniard set of nnrphological terns for the gross description of ticks. The problem is reasonably simple a.nd could easily be settled. Consideration should also be given to standardizing insofar as possi. ble the morphological terms used for mites and ticks. Reference to terms appearing in this report is provided in various text figures.

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Argasid ticks (Family Argasidae) are called haim ( |~—-:9 ) in Sudani Arabic. They are leathery or "soft" ticks_that secrete themselves in soil or in crevices, come out to feed for a short while, and then retreat to their hiding place. Two of the several argasid genera, Ar as and Ornithodoros, are common in Africa. The term argasid sho§I§'hot be construed to refer to the genus Argas alone. The sole African representative of a third argasid genus, Otobius, an ear tick, has been introduced from America into South Ifrica, Madagascar, and parts of Central and East Africa, but is not known to occur in the Sudan. A variety of argasids occur through. out most of the tropics and subtropics of the world. Fewer species live in temperate areas and very few inhabit arctic climes. Two species presently are distributed widely as a result of human transportation of domestic fowls.

Argasid eggs, deposited at intervals in small batches and total. ling only a few hundred, are laid in niches where females seek shelter. Chances that hatching larvae will find a favourable host near. by are reasonably good. larvae of the two Ornithodoros species in the Sudan are nonmotile and do not feed; this feature of their life cycle is unique in the genus. larvae of Argas feed on birds or bats, or less commonly on other animals, and remain on the host for several days to several weeks. Nymphs and adults of both genera feed for only a few minutes to a few hours at most, in marked contrast to the longer attachment time of nest nymphal and adult ticks of the family Ixodidae. There are at least two and sonetimes as man as six or nnre nymphal instars. Argasid adults take several blood meals, each of which is usually followed by a rest for digestion and, in the female, for oviposition. The genus Otobius, mentioned above, has nnre highly specialized feeding habits.

Argasid ticks are of considerable economic and medical importance in many parts of the world. However, at the present time they are apparently of less importance in the Sudan than in many other parts of Africa. As transportation facilities improve and urban areas become larger and unre settled, it is to be expected that Or.

nithodoros moubata will become more widely established in human'hEbi_ tations of southern Sudan.

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