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Dias, the more conservative approach of Zumpt for this difficult problem is utilized here.

Theiler and Robinson (l953B) stress the difference between this species and R. ca nsis Koch, 1844, and R. serranoi Santos Dias, 1950, two ticks no own to occur in the Sudan. In our territory, R. sulcatus is easily differentiated from all species but R.. sgpgpéneus In its coarser forms. In northern Sudan and usually in antral Sudan, R. s. san neus is usually not coarse enough to be confused wlthlR. s ca us, but in southern areas both species may superficially resemhle each other. Al. though Neumann's original description of R. sulcatus, together with its illustration, was excellent, th6'péhl§§lhg variation in R. s. san neus and the previously unrecognized fact that the latter species has a pattern of large punctations, no matter how densely punctate it may be, has long confused the real iden. tity of R. sulcatus. we have spent dozens of hours trying to differentiate among hundreds of collections of R. g. sang¥ineus before the arrival of'R. sulcatus specimens froh Dr. e or s reared series. Afterwards, no question concerning their specific differences remained.

If one turns a questionable male obliquely to the light, punctations of coarse R. 3. sggggineus will be observed to be relatively shallow, mohtly non scre e and sloping. Most im. portant, a few more or less clearly defined rows of widely. spaced, large, deeper, punctations will be noted among the shal. lower interstitial punctations. In R. sulcatus no row formation of large punctations is present, large punctations are numerous and deep, and medium size punctations are also deep. Specimens, if well preserved, should be briskly rubbed with damp tissue paper until their surface shines in order best to distinguish these characters.

In females, the relative isolation of large punctations among small or medium size ones usually differentiates R. s. san neus fronig. sulcatus in which large and medium size phnctatlhhs are indiscriminately scattered. The actual relatively greater length of the sulcatus scutu, which gives a first impression of being even longer than it is, easily distinguishes most specimens.

Some variable R. s. sgpguineus females may so closely approximate this elongate scutal appearance that care must be used when apply. ing this character.

Material referred to as R. sulcatus by Enigk and Grittner (1953), in their remarks on the Breeding and biology of ticks, should be re.examined for identity.

IDENTIFICATION

The diagnosis presented below is modified from Theiler and Robinson (l953B).

Male: Size small, averaging 2.5 mm. long and about 1.5 mm. wide (Neumann's specimens from 2.9 mm. to 3.4 mm. long and from 1.5 mm. to 1.8 mm. wide). Scutum narrow anteriorly, widening posterior of level of eyes, surface slightly convex, shiny. Lateral grooves discrete and pronounced, may contain large punc. tations; in some specimens extended to include penultimate fes. toon. Posteromedian and paraedian grooves widely elongate, wrinkled. Punctations deep, medium to large size, dense, some confluent; fewer laterally but some on festoons, scapulae, and lateral folds. Eyes flat, may be bounded by a few large puncta. tions. Coxa I may have a dorsal, unpointed hump. Basis capituli one and a half to two times as wide as long, with pronounced lateral angles at anterior third of length (Neumann's original, frequently reproduced illustration of this species shows the basis capituli extremely wide and pointed, most probably the artist's impression, drawn foreshortened, gained from a downward. pointing capitulum). Adanal shields typically like those of large

R. s. sanggineus but in some specimens they may be more elongately rounde t e inner margin emarginate (as is common in smaller

R. s. san uineus)- an approach to the sickleshape is seen in a smell ~.’

Female: Medium size, unengcrged about 3.00 mm. long and 1.75 m. wide (Neumann: 3.0 mm. x 1.5 mm.). Scutum flat, shiny, rich brown, emargination wide; as broad as long or slightly longer than broad, but appearing long due to the pronounced lateral grooves and the somewhat tapering, sinuous posterior margin (Neumann: 1.5 mm. x 1.25 mm.). Cervical pits short, deep; cervical grooves short and inconspicuous. Lateral grooves pronounced, with external ridge, and picked out with irregular punctations which may be confluent. Eyes large, flat, flush with surface, may be bounded dorsally by a few large confluent

punctations. Punctations medium to large, deep, somewhat un. evenly densely scattered, sometimes confluent, extending onto lateral folds. Basis capituli about three times as broad as long; cornua short, blunt points; lateral angles fairly sharp at midlength; surface not so heavily punctate as in male; porose areas circular, a little more than their own diameter apart. Palpi slightly longer than basis capituli and twice as long as broad, segments 2 and 3 as long as broad, segment 1 visible dorsally.

The larva and pypph have been described and illustrated by Theiler and Robinson (19538).

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Figures 313 and 314, 6', dorsal and ventral views Figures 315 and 316, Q, dorsal and ventral views

RHIPICEPHALUS SUPERTRITUS
an pec mens
PLATE LXIOCVII

.. 767

RHIPICEPHALUS SUPERTRITUS Neumann, 1907(3).
(Figures 313 to 316)
mm msr_mucm S~ TICK

EQUATORJ1 PROVINCE REIJCRDS

6‘

2 Kajo Kaji cerus caffer ae uinoctialis Jan ,

1 Juba cerus cgfer Hnoctlalls Nov ($3

1 "Alangu... Ecerus c§'fer aegulnoc l is _ (SI) Acholi"

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The male in the Sudan Government Collection, collected by H. H. King, had been identified by him as R. falcatus. The collecting locality of this specimen may now be_just 1' nsi do the Sudan or just over the Uganda border.

DISTRIBUTION IN THE SUDAN

Upfir Nile: Sudan Government collections contain a male spec. imen, co acted from a dog at Bor by H. H. King, which had been identified and reported by him (1926) as H. sulcatus.

DISTRIBUTION

R. sufirtritus is an uncommon East African tick that ranges into Uen r rice and into the northern part of southern Africa.

CENTRAL M'RICA: CMERDONS (Schulze 19/+1). BELGIAN CONGO (Neumann I9U7'B,I9lI. Massey 1908. Nuttall and Warburton 1916. Bequaert l930B,l93l. Zumpt 1942B).

EAST AFRICA: SUDAN (In part as H. sulcatusz King 1926. Hoogstraal I95ZB).

ERITREA (HH collection from Nacta). UGANDA (Nuttall lot 2396 in BMNH collections, from Gombag. ICENYA (Lewis l93lA,C, 1933,1934). TANGANYIKA (Zumpt 191.213

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