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It should be noted that some gradation appears between the two African subspecies of g. leachii and that a few specimens do not conform strictly to the crl er a for one or the other form. The third subspecies, indica Warburton, 1910 of southern Asia, is more like the subspecies muhsami than like the subspecies

leachii, and is distinguishable from both by minor but apparently constant and valid characters.

Dr. G. Theiler and the writer for several years have been collaborating on a morphological stdy of considerable series of this species from a variety of hosts and localities. The results, with complete data, will be presented in a separate report. The variety humerosoides, common on canines, informally proposed by Theiler (I§Z§B, for the large, narrow, elongate form with extreme ventral projection of spurs, appears from this study to be an extreme body form of the somewhat variable H. 1. leachii and not a separate morphological or biological subspecies. In numerous long series of specimens from single hosts, gradations from this to less extremely narrow and elongate forms occu. There are, however, suggestions that the extreme form is a reflection of particular host factors, and application of some of the more con;

plex aspects of newer taxonomic concepts may eventually justify the name humerosoides.


Males. This long, narrow tick has tarsi II to IV gradually tapering; punctations numerous, mostly small, and discrete; palpi obtusely angled and widely triangular, widest at level of basal third, with lateral margin straight or very slightly convex but almost never concave; basally both dorsally and ventrally forming a conspicuous and usually strong spur just laterad of the point of insertion; palpal segment 3 with a retrograde spur that is long and tapering; basis capituli with lateral margins varying from almost parallel to somewhat divergent anteriorly and with cornua that are usually large and pointed; coxae always with a distinct basal spur overlapping the basal margin and with a number of long, conspicuous hairs. This combination of characters must be considered in separating males from those of other species and from the subspecies muhsami.

The scutum varies from about 2.3 mm. to 3.8 mm. long and from 1.2 mm. to 1.9 mm. wide; average specimens are about 2.6 m. long by 1.3 mm. wide. This length.width ratio is important in comparing this subspecies with muhsami, though a few intergrade specimens, with respect to this featue, do occur. The punctations, always nuerous and mostly comparatively small, are usually discrete; they cover the entire dorsum including lateral areas and festoons but frequently are reduced in the narrow, elongate area correspond. ing to the posterior median groove of rhipicephalids. The long, narrow lateral groove encloses the first one or two pairs of festoons; the closely approximated, arched cervical grooves usually extend to the anterior level of the lateral grooves. The scutal surface is more or less arched.

The palpi are notable for their wide, obtusely angled form. The lateral margin, either straight or very slightly convex in outline, distinguishes this subspecies from mhsami, but, rarely, a similar form occus on ticks with the short, Broad scutal type of muhsami. The recurved basal margin is typically broken both dorsally and ventrally by a strong spu just laterad of the point of insertion; while this spur is usually accentuated in large, narrow, elongate specimens it is surprisingly reduced in some individuals of this type. The ventral retrograde spur of palpal segment 3 notably is consistently strong, overlapping the base of segment 3, and narrow and tapering. Segment 3 is about half as long as segment 2. The basis capituli, typically, is elongate with strong, tapered cornua and with lateral margins slightly divergent anteriorly, but the length_width ratio and size and shape of the cornua is surprisingly variable, even in specimens in which the general appearance would otherwise lead one to expect that these features would be typical, and the degree of divergence of the lateral margins is also somewhat variable. The hypostome has 4/4 or 5/5 dentition.

The coxae are notable for the basal spur that overlaps the basal margin and for the presence of twelve to twenty long hairs on each (hairs may be broken or rubbed off in old or carelessly collected or preserved material). The size and position of these spurs always approximate those illustrated herein and are important in distinguishing this species from some others. In newly melted or fresh specimens, the numerous long hairs are a very character. istic feature of this species. The elongate tarsi taper gradually

apically and bear a small pad and claw; the claw curves distad of the apex of the pad.

Females. This sex closely recalls the male and while it is equally as variable it appears to be less frequently confusing with the subspecies muhsami.

The elongate scutum, from one fourth to one third longer than wide, posteriorly tapers gradually to a more or less narrow point. Scutal punctations are much like those of the male, and while they are frequently somewhat larger and less numerous than those of the male they are distinguishable from the consistently large and sparse punctations of mhsami. The cervical grooves gradually converge to the scutal midlength and thence diverge towards the posterolateral margins but do not reach these margins.


The palpal outline is like that of the male except that it is more elongate, the length of segment 3 more nearly equalling that of segment 2 than it does in the male; and the basal spur ventrally is absent or extremely reduced in the form of a bluntly rounded projection. The lateral margin, which as in the male is typically straight or slightly convex, is actually more readily and definitely usable as a diagnostic character because of its greater length; while this margin is very slightly concave in some specimens these are unusual. The basis capituli is definitely wider and shorter than that of the male and bears shorter cornua.

Coxal and tarsal characters are like those of the male; in spite of some variation they are not likely to be confused with nnst specimens of the related subspecies. _Z'In considering the female coxal spur as minute and the tarsus as "stout", Nuttall and Warburton (1915) must have been referring to specimens of muhsamii7


The body form of unengorged females is typically elongate and comparatively narrow, as in males, though the overall size is somewhat larger. Engorged females may become so large in the latter hours of feeding that superficially they resemble typical boophilid females.

The larvae and Eymph of this species, but not definitely refer; able to tfi) s subspecies, have been described by Nuttall and liar-bur. ton (1915 .


Figures 150 and 151, d‘, dorsal and ventral views Figures 152 and 153, Q, dorsal and ventral views

Sudan Specimens from wEIte..ta1'I§ Rongoose

.. 377..

(= 5. LEACHII INDICA (in Africa) or

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L N g d‘ HIUATGRIA PROVINCE REDCRDS 1 Torit Crocidura nyansae toritensis Feb 1 Torit IteIeri'x pruneri oweni Feb 2 Tarangore IteIerIx pruneri oweni Jun 2 1 Torit e ivora ca nsis a ssinica Jan 1 Torit Danis mesome as e onae Dec 3 l Torit Danie aureus soudanicus Apr (2) 2 1 Obbg ive tictis cive a congica Apr Tor t Divettictis civetta con ica Feb 9 Torit C'iTr?t"£lFt'iE ?iveE1CE 'E6§'_ glca Jun (2) 1. 9 Torit Civettictis cive a co ica Jul 1 2 Torit Cenetta ti Eina aeguatorillis Feb 2 15 Kapoeta er s es s ‘neus san neus Apr 1 l Torit I~ aIEiEcaT1Ha aIEl'ca%Ha Jan 15 Torit c eumla ica a ica a Mar 2 1.0 88 Torit c eunlla ica a ica a Apr (3; 1 ll. 39 Yei c eunlla ica a ica a Apr 2 1 Torit e is ca an ae Nov 1 Kapoeta De us cagnsis subsp. Apr 1 Ikoto Ce us ca nsis crawsh i Feb 1 Ikoto EHLCh~E~!_Smth11 Dec 1 Torit Domestic dog ii


Bahr Kl. Ghazal: 12:36", 499, black.1egged mongoose, Galua1..Nyang Forest, 27-May I953, E. T. M. Reid legit. 16, same host and co]_'Lec..

tor, Yirol, 22 January 1954. 566‘, e erix eri oweni, Galual... Nyang Forest, 21. February, 1953, H. Hoogstrag Iegit. 13‘, lo,

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