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RHIPICEPHALUS KOCHI Dônitz, 1905.
(= R. JEANNELI Neumann, 1913).
(Figures 269 to 272)

THE CENTRAL AFRICAN HIGHLAND BROWN TICK

L N Q C. EQUATORIA PROVINCE RECORDS l l Nagichot domestic COwl Dec 2 Kipia host not stated Dec (BMNH) 2 Kipia on grass - (Weber 1948)

The Nagichot specimens, from a cow at 6500 feet elevation in the Didinga Mountains, were collected by Mr. H. B. Luxmoore in 1951. The British Museum (Natural History) specimens, found unidentified in their collections, were taken by Mr. J. D. MacDonald in 1938 at Kipia, 8800 feet elevation, in the Imatong Mountains. The Weber specimens from the same locality, but reportedly at one hundred feet lower elevation, were identified (Weber 1948) as R. bursa. Weber's specimens, kindly loaned by Dr. J. Bequaert, were independently identified by Dr. Theiler and by me as R. kochi.

R. kochi is known in the Sudan only from the high mountains in the central part of the eastern half of Equatoria Province.

DISTRIBUTION

R. kochi, a tick of the more humid and temperate highlands of Central Africa, less commonly also inhabits the highlands of East Africa (see also Ecology of R. compositus, p. 625). Records previous to 1950 should be accepted # caution.

CENTRAL AFRICA: BELGIAN CONGO and RUANDA-URUNDI (Schoenaers 1951A,B. Rousselot 1953B. Theiler and Robinson 1954. Van Vaerenbergh 1954).

EAST AFRICA: SUDAN (As R. bursa: Weber 1948. Hoogstraal 1954B).

UGANDA (Wilson 1952,1953). KENYA (Neumann 1913. Anderson 1924A.B. Lewis 1931A,B,C,1934*: Daubney 1933. Binns 1952). TANGANYIKA (Dönitz 1905,1907, cf. HOSTS below. Neumann 1913. Morstatt 1913. Moreau 1933; cf. REMARKS below. Theiler 1947. Schoenaers 1951A).

HOSTS

R. kochi is known chiefly from domestic cattle. Duikers and other forest antelopes may be presumed to have been its original hosts. Animals on which immature stages feed are unknown.

Domestic animals: Cattle: Dönitz (1905,1907). Lewis (1934). Schoenaers (1951A,B). Rousselot (1953). Theiler's records are from cattle. Dönitz's material from Soadani and Lindi was probably taken from introduced cattle. Dogs (Lewis 1931B).

*Wild animals: Lion and spurfowl (Lewis 1934). Buffalo (Theiler, unpublished).

BIOLOGY

Life Cycle

Eggs hatch in 24 days and larvae feed for five or six days according to Rousselot (1953B). No other details are known.

Ecology

Schoenaers (1951A,B) found R. kochi only above 2000 meters elevation in Ruanda-Urundi and specimens sent to Rousselot (1953B) were from altitudes between 2400 and 2500 meters elevations. Wan Waerenbergh (1954) also reported the same altitudinal range, and Theiler and Robinson's (1954) Congo localities are at similar elevations. As already noted, Sudan specimens have been taken

*Lewis (1934, p. 41, footnote), states that these specimens may be R. capensis.

only between 6500 and 8800 feet elevation. Wilson (1953) states that this tick is limited to upland forests in East and Central Africa, and work on its ecology and of that of another upland

species, R. compositus (= R. ayeri) is in progress. See also Ecology of R. compositus (p. #

When present, this tick often appears in great numbers (Theiler and Robinson 1954). Its specialized high altitude preference may account for rarity in collections and for paucity of records.

DISEASE RELATIONS

Cattle: A vector of East Coast fever, Theileria parva, though, on epidemiological grounds some observers have indicated that this species is not a vector.

REMARKS

Our present knowledge of the biology, morphology, and taxonomy of those heavily-punctate rhipicephalids that have shallow lateral grooves or none at all is in an unsatisfactory state. This complex may be referred to as the "R. ziemanni, group" in place of the "R. aurantiacus group" of Zumpt (19.3B). Subsequently, Zumpt (1950A) has included several species of this group, previously considered as valid, in synonymy. Species now recognized are: R. ziemanni Neumann, 1904 (= R. aurantiacus Neumann, 1907, and R. cuneatus Neumann, 1908), R. Kochi Dönitz, 1905 (= R. jeanneli Neumann, 1913), R. masseyi Nuttall and Warburton, I - R. attenuatus Neumann, )* and 7 = R. tendeiroi Santos Dias, T95O(E) 7 and R. mihlensi Zumpt, 1943(B). To this group should be added R. hurti Wilson, I954 of Kenya and R. serranoi Santos Dias, 1950(G) of Mozambique. It is possible that these two species may eventually be shown to be £ punctate specimens of R. kochi. Theiler states (correspondence that from evidence presently available, she agrees with the above

synonymy 7.

*It appears that the R. attenuatus of Santos Dias (1954D) from Ruanda-Urundi is R. kochi, since Theiler, Schoenaers, and Vaerenbergh have found R. kochi "most plentiful" at the same collecting sites from which Santos Dias' material was sent. (Footnote continued on next page).

A more comprehensive morphological, taxonomic, and biological study of this group is indicated. Large series of specimens from many areas are required to solve these problems, which are outside the scope of the present work. In the known Sudan tick fauna, R. kochi is easily distinguished. The remarks below are only for local use and are not sufficiently detailed for differentiation of material from elsewhere in Africa. The Sudan material noted herein was identified by Dr. G. Theiler. Miss J. Walker is now reviewing this group.

Four specimens, identified as R. kochi by E. A. Lewis, were found by Moreau (1933) in the stomach of a tick bird in Tanganyika. I have examined these specimens, in the collections of British Museum (Natural History), but cannot identify them to species.

IDENTIFICATION

Males: Lateral grooves are replaced by a line of almost continuous punctations, the posteromedian groove is merely a fine, shagreened line, and the paramedian grooves are indicated by shagreening only. A blunt dorsal hump of coxa I is present. Scutal punctations are numerous, close or contiguous, mostly moderate

There has been some difference of opinion among specialists over which of the synonymous names, attenuatus or masseyi has priority. The background is as follows: Neumann's name attenuatus was published on 20 March, 1908. Although Nuttall and Warburton's name masseyi was read orally at a scientific meeting on 28 December 1907, it was actually published on 10 March 1908. Therefore, according to Opinion 15 (July 1910) of the International Code of Zoological Nomenclature (reconfirmed at the Paris conference, 1948), in which it is stated that, "The mention of the new name in a paper presented orally before a meeting of any kind" does not constitute publication, the question is decided definitely in favor of the name masseyi, which was published ten days earlier than attenuatus. Authority # the publication dates of these two papers is the Index-Catalogue of Medical and Veterinary Zoology, part II, pages 3539 and 3627 (1950). Some workers consider that the Nuttall and Warburton paper was published in May 1908, which, if true, would reverse the prior name of this tick.

size, with a scattering of widely separated large punctations among them. Certain populations have fewer punctations that are exceptionally shallow. Cervical pits are deep but cervical grooves are absent or very short. The central festoon, but not adjacent festoons, may be extended in engorged specimens. Basis capituli has prominent lateral angles. Body outline is pear-shaped. Adanal shields are distinctive, as illustrated (Figure 270).

Females: This sex also lacks a lateral groove and has scutal punctations similar to those of the male, but these punctations may tend to be somewhat larger. The cervical grooves are pronounced and gradually converge to the level of the eyes, thence diverge almost to the posterior margin of the scutum. The scutal shape is subcircular, slightly wider than long.

Note: Some variation is to be expected in specimens referable to R. kochi but the significance of such differences is difficult to evaluate at this time.

The larva and nymph have been briefly described and illustrated by Rousselot 3B).

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