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cnrrzum 4111101. Bmmn couco (Schwetz 19270. Bequaert 19301, 1a,193‘.l""'1"_I1'iIIF. one ondelli 19301).

NOTE: According to Theiler (correspondence), the record for Ruanda..Urundi by Santos Dias (19549) is in error.

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ETHIOPIA (Warburton 1910. Neumann 1922. Stella 1940). ERITREA (Stella 1940). ITALIAN scmLILnm (Pavesi 1895. Paoli

1916; Tonel1i_Rondel1i 1930A. Niro 1935. Stella l938A,l939A, 1940 .

mm (Neumnn 1912,1913,1922. Neave 1912. Anderson 19241, B. Brassey..Fdwards 1932. Lewis 19321,1934). ucmm (Neave 1912. Mettam 1932,1933. Wilson 19500). TANGANYIKA (Gerstdcker 1873. Neumann 1907C ,l91OB ,l913 ,1922. Morstatt 1913. Bequaert 1930A.

Evans)l935. Schulze 1944A. J. B. Walker, Impublished, see HOSTS below .

SOUTHEIN AFRICA: ANGOLA (Karsch 1878. Howard 1908. Bacelar 1%O~Howud 1908. Bedford 19328. Santos Dias

nammm mmnssn (Hoogstraal 19540). sovrmm RHCDESIA

(Jack 1942. Specimens from Sebungwes Theiler, correspondence).
NYASALAND (Old 1909. Neave 1912. De Meza 1918A).

sorrruwzsr AFRICA (Theiler, unpublished). UNION 0; sown AFRICA (Denny 1843. Gerstacker 1873. Howard 1908. Donitz 191019. Breijer 1915. Curson 1928. Bedford 19328. The localities in the first four references cannot be accepted without question; only Zululand records are sure (Theiler, correspondence).

Specimens of "subspecies rmaculatus" (see REMRKS below) from "Zambeze" were reported by eumann 907C,19lOB).

NOTE: Records from ZANZIBAR (Howard 1908, quoted by later

authors) probably result from the use of this nam for East Africa by early writers.

I-KBTS

The black rhinoceros, Diceros bicornis subspp., and the white, or square-lipped, rhinoceros, deratotherium simum subspp., are listed as hosts by all authors. TE Eats o our Equatoria Prov. ince specimens listed above, if they were rhinoceros, represent both genera inasxmlch as only the black rhinoceros occurs near Magwe east of the Nile and only the white rhinoceros occurs across from Nimnle west of the Nile.

In Tanganyika each of several rhinoceros hosts of various ticks yielded small numbers of this species (J. B. Walker, unpublished).

King (1926) suspected, from the places in which he found specimens of this tick, that it may also attack the hippopotamus. Evans (1935) recorded domestic cattle and sheep as hosts in Tanganyika. Lewis (1934) mentioned a domestic donkey in Kenya and De Meza (19l8A) took specimens from domestic cattle in Nyasaland and from elephants in Tanganyika. Neumann (l90'7C,l9l0B) listed an eland as host, and Mettam (1932) noted the jackal from Uganda.

BIOIDGY Unstudied. Specimens are connnonly reported from the hosts‘ genitalia. DISEASE REIATIONS

Unstudied .

REMARKS

That the specific name rhinocerotis de Geer (1778), used by many authors for this species, actfilly applies to a distinct species in the genus Amblyomma was indicated by Donitz (19103).

Schulze (l932A) suggested that D. rhinocerinus be placed in

the genus Amblyocentor on the basis Br minor morpfilogical pecu.. liarities. There ls, however, little utility in fragmenting tick

genera on the basis of insignificant characters. Amblyocentor is therefore considered as a subgenus of Dermacentor.

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A few male specimens have the anterior spots of the scutum partially or completely fused, thus resembling the female scutum. Neunann (19070 ,19l0B) described the subspecies Ermaculatus on the basis of these differences. Subsequent investigators with the exception of Tonelli_Rondelli (1930.11), have disregarded this name and considered these characters to be no more than individual

variation (Bequaert 1930B).

A "'pzrovisiona.l name", D. rhinocerotis aran is, was applied by Lewis (1931., p. 39) to specimens of variable coior but after comparison with other specimens this name was withdrawn (footnote of

same page).

Females have two large patches of reddish brown hairs and scattered lighter hairs near the posterior margin of the body dor.. sally. These, and the cuticle of this species, have been studied by Schulze (19u.A) and Jakob (1924). Schulze (191.1) noted features of the tarsus and haller's organ, and (1950A) of the dentition of

this tick.

IDENTIFICATION

Key characters readily separate and identify the two Dermcen_ tor species discussed in this report.

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HAEMAPHYSA IS

INTRODUCTION

Haemaphsalids are so small and inconspicuous, except when the females become greatly engorged, that they are seldom ads. quately represented in collections. Collectors frequently over. look them when larger and more colorful ticks are present. Many species show a marked predilection for seldom examined hosts such as hyraxes, birds, and hedgehogs. Some haemaphysalids appear to be actually quite rare in natue.

In tropical and southern Africa, the genus Haemapgysalis is represented by the ubiquitous H. leachii subspp., c e y a car.

nivore parasite, and by appoxImateIy fifteen less common species. In the nearby Madagascan archipelago, among whose ten known endem_ ic tick species are nine haemaphysalids, most are distinctly re. lated to the Oriental fauna. Asia has some fifty or more haemaphy. salid species, which, in proportion to the total tick fauna, are to that continent what rhipicephalids are to Africa. A dozen forms are listed in the Russian fauna (Pomerantzev 1950). Of a total of eighteen ixodid species in the Philippines (Kohls 1950), not including the cosmopolitan kennel tick, one third are haema. physalids. The Americas and Euope claim only about five species each.

Since Nuttall and Warbuton's (1915) revision of this genus, the African haemaphysalid fauna has received but little attention from biologists, systematists, or collectors. Many records in. cluded here represent considerable extensions of known range. Obviously, some few African species remain to be discovered and described. Differentiation of most African haemaphysalids is relatively easy, either by certain combinations of characters or by unique characters for individual species. Morphological char. acters and facies of most species are comparatively quite constant. An important exception is H. leachii subspp., among the African forms of which there is very considerable variation.

Haemaphysalids are usually three_host parasites, although exceptions do occur. The life cycles of H. 1. leachii and of H.

aciculifer have been fairly well studied In the Iabzratory, but

few reliable biological data are available for African species. Factors governing morphological and biological variations of Q. leachii subspp. pose an especially intriguing problem.

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Medically, the only African haemaphysalid of known importance is Q. 1. leachii, a vector of boutonneuse fever (tick typhus) of man and of-malignant jaundice of dogs. The sae species may also

be a reservoir of Q fever. The high potential of H. b¥3§£§§§i as a medically important species has been recently sdgges e

others probably eventually will be incriminated in disease transmission of academic or practical interest.

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