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from two warthogs, same locality as above, 7 June 1953, and 8 January 1954, collected by E. T. M. Reid and P. Blasdale. Numerous other specimens collected in the same area in July by the same persons, but without host data. lo', , recently molted clinging to grass (with Dermacentor rhinocerinus), 25 miles west of Yirol, 23 November 1957, E.T. M. Reid regist. 1038 and 22% (some of which intergrade with R. simus simus) (cf. IDENTIFICATION below), from elephant near Kenisa, May 1953, E. T. M. Reid legit. Sudan Government collections contain other Kenisa area specimens from elephants, collected in 1911, which show similar intergradation with R. s. simus (cf. REMARKS below). Mr. Reid has sent me numerous specimens from three elephants shot near Yirol; these are typical R. S. simus.

DISTRIBUTION

R. simus senegalensis is a West and Central African tick with scattered loci in more humid areas of East Africa as far south as northern Nyasaland.

WEST AFRICA: NIGERIA (Unsworth 1952. As R. simus: Simpson 1912A, p. 325; det. by Nuttall and Warburton as R. simus falcatus; see p. . As R. simus longoides: Unsworth 1949, Mettam 1950, Gambles 1951). # (Koch 1844. Rousselot 1951, 1953B. As R. simus longoides: Williers 1955). SIERRA LEONE, IVORY COAST, GOLD CONST, (Zumpt 1943A*). PORTUGESE GUINEA (Tendeiro 1952B,C,1953, 1954).

CENTRAL AFRICA: CAMEROONS (Zumpt 1943A*. Rageau 1951, 1953A, B). FRENCHTERUATORIAL AFRICA (Zumpt 1943A*. Rousselot 1951). BELGIAN CONGO and RUANDALURUNDI (?As R. simus shipleyi: Bequaert 1930B,1931. Zumpt 1943A*. Rousselot 1953B. Theiler and Robinson 1954. Van Vaerenbergh 1954. See HOSTs below).

EAST AFRICA: SUDAN (In part as R. simus and as R. falcatus: King IS26.THoogstraal 1954B,C). UGANDA and TANGANYIKA (Hoogstraal 195 c. J. B. Walker, unpublished; see HOSTs below).

*All Zumpt (1943A), records are under R. simus longoides subsp. nov. which Zumpt (1950A) later synonymized under R. simus Senegalensis.

SOUTHERN AFRICA: NYASALAND (As R. falcatus: several specimens, NuttaTTTot T099A in BMNH, with numerous R. longus, from Chitipa Valley, Dowa District, 1910, J. B. Davey i:#

NOTE: Koch's (1844) record from Egypt, subsequently quoted by numerous authors, is either based on a mistaken locality label or on a specimen of R. S. sanguineus. Koch based his original description on females, only, # Senegal (French West Africa) and Egypt. See REMARKS below.

HOSTS

Like the subspecies simus, R. simus Senegalensis attacks a variety of larger game and domestic animals. The immature stages

probably feed on rodents, but no data concerning their host preferences are available.

Domestic animals: Cattle (Zumpt 1943A*, Rousselot 1951, 1953B, Unsworth T352, Rageau 1953B, Hoogstraal 1954C*#). Horses (Nuttall lot 182 in BMNH, see NIGERIA above. Zumpt 1943A*). Pigs (Rousselot 1951, 1953B, Rageau 1953B). Sheep (Rousselot 1951, 1953B). Dogs (Rousselot 1951, 1953B, and Uganda and Sudan records above).

Wild animals: Bushpig (Zumpt 1943A*). Warthogs (Nuttall lot 1099A, see NYASALAND above. Rousselot 1951, 1953B. Sudan records above. Uganda specimens in BMNH). A "Giant eland (Bequaert 1930B, 1931, see BELGIAN CONGO above) 7. Wildebeest (Walker, unpublished). Bongo (Rageau 1951). Roan antelope (Sudan record above). Buffalos (Hoogstraal 1954C*, Van Vaerenbergh 1954, Williers 1955, Theiler, unpublished. Walker, unpublished. Sudan records above). Forest dwarf buffalo (TendeiTO £) Elephants (Common hosts in : El Ghazal; recorded above). Hunting dog, Lycaon pictus (Sudan record above). Lion (Congo specimens in MCZ s: collections).

*All Zumpt (1943A) records are under R. simus longoides subsp. nov. which Zumpt (1950A) later synonymized under R. Sims Senegalensis.

*My 1954C report of domestic cattle should be wild buffalo
("Bos caffer" on label).

NOTE: Rousselot (1951,1953B) records specimens from the cane rat, Thryonomys swinderianus. These specimens should be checked against R. Simpsoni. In the same reports he states that the shorthaired rat, Fraomys jacksoni, is a host in the Belgian Congo. Unless this note #: parasitism by an immature stage, this animal would be a most unusual host. Santos Dias (1952C,1953,

1954) states that one nymph along with many males has been taken from a forest dwarf buffalo.

BIOLOGY

Life Cycle

It cannot be determined whether the life cycle data presented by Rousselot (1953B, p. 92) under R. simus senegalensis concern this subspecies or the subspecies simus; other remarks under the same heading refer obviously to the subspecies simus. Unfortunately, no clues to the life cycle of R. simus senegalensis in nature are available. Rousselot (1953B, p. 91) claims that this is a three-host subspecies.

Ecology

This is a tick of West African higher rainfall areas. Populations that range into East Africa appear to be confined to animals found in forests, in more heavily vegetated savannah, and in the vicinity of lakes. The Boma Plains buffalo on which some Sudan specimens were taken was probably a migrant, for the Boma Plains are too arid for many months of the year to allow this tick to survive.

According to Unsworth (1952), in Nigeria the subspecies

senegalensis "appears to have approximately the same distribution as ... simus, but it is not so common".

DISEASE RELATIONS

It is claimed that specimens of R. simus Senegalensis naturally infected with Q fever (Coxiella burnetii)The VeTEeen found in Portugese Guinea.

REMARKS

Koch (1844) based his original description on females only. His material was reported as from Senegal and Egypt. It is most likely that the Egyptian record is due to a mistaken locality label. Just how the Senegal specimen has been associated with what is today called R. simus Senegalensis has not been determined. A female specimen of t ... simus group from Koch's time would be difficult to identify with any degree of certainty, especially to subspecies. Neumann (1911) synonymized Senegalensis under R. simus. Zumpt (1943A,1950A) described what is now considered as E. simus senegalensis.

A number of the Sudan and Tanganyika collections listed herein were sent to Santos Dias for identification, along with some specimens of R. lo . The R. simus Senegalensis material was determined by him as E. longus and the R. # material was labelled R. capensis #

Zumpt (1943A,1950A) warns his readers that heavily punctate R. simus senegalensis may superficially resemble R. longus. The R. Tongus of # Dias (1953D) appears to be what Zumpt considers a heavily punctate R. simus Senegalensis.

A further note is necessary concerning collections listed above as simus-senegalensis intergrades from elephants near Kenisa, Bahr El Ghazal Province. These are comparatively small, brownish specimens, with simus scutal punctation, posteromedian and paramedian grooves absent or very faintly indicated, and adanal shields showing every degree of variation from the most typical simus type

to the most typical senegalensis type. These series nicely corroborate Zumpt's treatment of Senegalensis as a subspecies of simus.

IDENTIFICATION

Male: Within the R. simus group, as described in the key and under R. simus, males of the subspecies senegalensis are referred to a group with sickleshaped adanal shields. "The scutal outline is definitely wider in relation to length than in most specimens of R. s. simus and the scutal surface is flat, not arched as in

the subspecies simus. The posteromedian groove is long and narrow, the paramedian grooves are shorter and wider; these three grooves vary in depth and distinctness from specimen to specimen but are never deep or strikingly apparent. The distribution of large. scutal punctations is an important criterion in distinguishing this tick. On the anterior three-fifths of the scutum, large or moderate size punctations are arranged in four irregular rows of three to six puncations each. On the posterior two-fifths, there are from six to twenty large punctations in one and a half to three irregular, closely grouped rows on either side of the posteromedian groove. Scattered about the paramedian grooves are four to eight scattered large punctations. The interstitial punctations are always very shallow but they may vary in distinctness from almost absent to large enough (though still superficial) initially to confuse the basic pattern of large punctations as described above. On close examination, however, this pattern is easily discernible. The lateral grooves are usually deep and long. One or three median festoons may protrude when engorged. The average size is that of the largest R. s. simus and the color, while usually jet black, may also be brownish, especially in smaller specimens.

Female: This sex is difficult to distinguish from that of the subspecies simus, but in general its larger size, similarity of scutal punctation in comparison with that of the male, and its association with the male refers most specimens to the sub

species senegalensis.

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