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and Neumann 1896 from River Anseba, "Upper Nubia". Franchini 19293, E. Tonelli-Rondelli 1930A. Niro 1935. Stella l938A,1939A,l940). FRENCH SOMALILAND (Neumann 1922. Brumpt 1936. Stella l938A,l939A, 1940). BRITISH SOMALILAND (Pocock 1900. Drake-Brockman l9l3A,B, 19l4,l9l5A,B,1920, biology and medical implications in part mixed with 0. moubata. Neumann 1922. Stella 1938A,1939A,l940. Ander.. son 1947. Heisch 1950A. Falcone 1952, erroneous disease rela. tions). ITALIAN SOMALILAND (Brumpt 1908B. Lees 1914. Paoli 1916. Franchini 1925,l927,19293,E,l934. Tone1li_Rondelli 1930A, 1931. Mattei 1933. Niro 1935. Massa 1936A,B, medical implica. tions questionable. 1-Ioise 1938,1950. Stella l938A,1939A,l940. Lipparoni 1951,1954. Giordano 1953).

KENYA (The Q. savigr_1yi of Karsch 1878 refers to Q. moubata. Dbnitz 1906. Neave 1912. Neumann 1912. Anderson l924A,B. Mackie 1927. Brassey_Edwards 1932. Lewis l931A,C ,1939A. Heisch 1937,195lA. Walton 1951). UGANDA (Bruce et al 1911. Neave 1912. I-iettam 1932). "'

Z-?TANGANYIKA: ?As 0. morbillosusz Gerstgcker (1873). Neumann (l90l,l90'7C,l910B_,l9T].-F} oward (1908) ?quoting Neumarm. Absent in Bukoba: Morstatt (1914). The presence of this tick in Tanganyika remains questionable._7

SOUTHERN AFRICA: [2AmoLA= Neumarm (1896) listed specimens from Eddana that Bequaert (l930A) quite logically believes were 0. moubata. Subsequent statements Santos Dias 195(1) are merely a repetition of Neumann and diseas(e relations are incorrect. "RHCDESIA": Report of Lounsbury 190(1) obviously referring to Q. moubata, quoted by other authors. No,subsequent reports of Q. oov_—""i n . ?M('EAl§BIQUE: Neuma.nn (1896) ?should be( _g. moubata. Bunsbfiy (190(I2 should be 0. moubata. Theiler l 43E) states 9. savi n ' doubtfully recorded -53% possibly present. Santos Dias evidence not presented. Mozambi ue records are considered incorrect by Theiler and Robinson ((1954)._7

NYASALAND (Wilson 1950B). BECHUANALAND (Bedford 1926,1927, l932B,l934. Theiler and Robinson 1951.). soummsr AFRICA (Iouns..

bury l90<I3, possibly referring to 0. moubata. As 0. avimentosus: Neumann 1901,1911. Donitz 19070 ,l9l0§. Howard 1908. Trommsdorff

1914. Bedford 1926,l927,l932B,193l.. As 0. moubata.: Miinnig 191.9.

Lesson 1953. Theiler and Robinson 1951.. Theiler and Hoogstraal. 1955). UNION or some AFRICA [Leuhsbm-y 1s99c,1900s,c (confused with 0. moubata), 1903B,l90l..l. Howard 1908. Donitz 191013. Bed. ford I9é0ZI926',1927,1932B,1934. Alexander 1931. Bedford and Graf 1934,1939. R. du Toit 191.2B,c,191.7A,B. Theiler and Robinson 1954. Theiler and Hoogstraal 1955_.7

NEAR EAST: MEI (Nuttall st e1 1908. Patton and Gregg 1913. C~. Hoogstraal msJT -IBM! (Mount 1953. Hoogstraal, ms.). PALESIBJB (Theodor 1932. smth 1936 quoted by Brumpt 1936. Bodenheimer 1937). IRAQ (Lesson 1953).

MIIILE EAST: INDIA (Christophers 1906. Neumarm 1911. Patton and Cragg 19B. Donovan 1913. Fletcher 1916. Gross and Patel 1922. R80 and Ayyar 1931. Sen 1938. Sharif 1938. Kapur 191.0. Joehi 1943). cmmon (Nuttall st e_1 1908. Brumpt 1936. Crawford 1937. Chow, Thevasegayam, and-'l'ha.r'unm'a_']ah 1951.).

HOSTS

Camels are most frequently mentioned as hosts. Q. savigl. appears to be present in most areas id which dromedaries are used. Fowls are sometimes attacked and all domestic animals my serve as hosts (Lounsbury 19008). For instance, this tampan is common in cattle yards at Mawar, India (Joshi 191.3) and under trees where nmles are tethered in Somliland (Lipparoni 1951). Htman beings are frequently bitten, especially when they sleep in canal yards or sit under trees counnonly used by domestic animals for shade. Amy laboratory animal may serve as a host. Dogs are satisfactory laboratory hosts (Lounsbury 1904A).

Game animals are said to be attacked, but evidence is scant. The rhinoceros, lion, and buffalo may serve as hosts in Kenya according to Walton (1951). Neumann (1912) reported numerous specimens from a Kenya locality where a giraffe had been standing.

BICLOGY

Life Cycle

Eggs of O. savi are deposited in sandy soil where adults hide. muv1~ as, observed by cuhnrre (1922) at 3o°c.,

laid from 100 to 1.17 eggs, averaging 219. Other individuals that had fed four tines laid five egg batches totalling about 900 eggs over a thirteen month period (Patton and Cr g 1913). The embryonic development, described by Christophers (1906, is essentially like that of Q. moubata.

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Larvae, like those of 0. moubata, are nonmotile and do not feed. Although some undergo eaysis in the egg, mst larvae free themelves from the eggshell before melting to nymphs (Bunliffe 1922). After splitt the eggshell, larvae molt to'nymphs in five hours (Davis 19% to ten hours (Patton and Gregg 191,3).

Four nymphal instars over a period of about 81. days and seven nymphal feedings were observed by Patton and Bragg (1913). (Jun. liffe (1922), on the other hand, noted that males appeared after four to six melts and females usually after the sixth molt. Rea. sons for differences in number of instars among argasids rennin to be ascertained.

The very active nymphs commence feeding two or three days after melting and require fifteen to thirty minutes to reach re. pletion. Adults normally feed for similar periods but the pre. sence of both stages along remote camel trails would indicate that on occasion some tampans may remain longer on the host.

Females in 0unliffe's (1922) stuiies lived between 292 and 120 days at 30°C. and for an average of 775 days at 22°C.

Spermatophores superficially similar to those of Q. mubata are utilized by this species (in Egypt), although Christofirs (1906,) ani Nuttall a.nd Merriman (1911) questioned their presence.

Other details of the life cycle have been re rted by the above mentioned observers and by Rousselot (l953B . However, more extensive and refined studies are still necessary.

Ecolog

Q. savi , among the tick species studied by lees (1947), shows the grea est ability to limit water loss at high temperatures. The critical level for this species is 75°C. while for 2. mubata

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it is 63°C. Even xerophilic hyalomnns abruptly increase water loss at 45°C. (cf. page 154). This factor explains in part how the eyed tampan can exist in deserts where little other life is sustained. Cun]_iffe's (1922) stuiies, from which he concluded that the temperature and humidity requirements of both these tampans are much the same, should be repeated with special at. tention to extreme levels.

Famous for the viciousness of its attack, this tampan is usually well known wherever it occurs. Natives quickly lead one to infested animal corrals, trees under which lien and beasts rest, and well sides where the eyed tampan is superficially burrowed awaiting its prey. In Sonnliland, Lipparoni (1951) reported,

2. savi is common under trees where soldiers tether their mules . moubata infests huts beside these trees. Although the adventitious presence of 0. savi§% in buildings must be expected, early records from human 1 ations appear to be based on misidentification. For instance, Drake.Brockman's various reports of O. savi i in British Somaliland buildings have been questioned by erson (1947). Anderson found 9. savigx_i[Jl_. ex. clusively outdoors in the same area, and O. moubata, previously thought to be nonexistent in the area, exEeedIng1y common in huts and coffee houses.

we have never observed 0. savi n ' in sites directly exposed

to the sun. Indeed, at the Ehartdum quarantine one may see a long, seething line of thousands of hungry tampans helplessly confined to the shade of a row of acacia trees. A few yards away, separated only by the hot, nine o'clock sun, newly arrived cattle tied to a post fence tempt the tampans to cross the glar. ing strip. The next morning, in the coolness of seven o'clock, those tampans under the trees are all blood bloated and resting comfortably in the sand, others are dragging back from their hosts across the now nonexistent barrier, and the legs of the cattle are headed with yet other podshaped ticks taking their fill of blood in a regular line just above the hoof.

Laboratory rats and mice, as noted by Heisch (l950A), assail this tampan. Rats feast on nymphs and adults. Mice commonly assault nymphs, but only particularly bold mice attack adults. These rodents, in turn, facilely escape bloodthirsty but lumber... ing adults, although small, active nymphs more easily attack them. Predators in nature do not appear to have been reported.

REMARIS

Ghristophers' (1906) extensive study on morphology and digestion of Q. savigzl; has been reviewed in the section on Q. moubata, which also con ains a number of other data pertaining to both species.

The nymphal instars may be approximately determined accordi to Cun1iffe's (1922) data, also presented by Campa.na..Rouget (1954 .

The haller's organ of 0. savigz_:E has been described and illustrated (Schulze 191.1). "

Jakob (1924) used this tampan to illustrate certain theories separating the ixodids‘ from the argasids on the basis of differences in external grooves, ridges, and prominences. He did not believe, as a result of these studies, that Argas developed from Ornithodoros, but rather that both genera had a common origin in the Uro§Idae,

a member of which, Discoama africana Vitzhum, was illustrated.

DISEASE REIATIONS

MAN. The bite of Q. savi may have severely painful seque. lae but this tampan has never en found infected with pathogenic organism in nature, and transmission of pathogens has not been demonstrated until recently. Even the earlier assertions that the

eyed tampan transmits human relapsing fever (Borrelia spp.) have been cast into considerable doubt by subsequen research.

DOMESTIC ANIMAIS. Camels and cattle suffer greatly and may even be killed by the volume of blood lost to numbers of eyed tampans in their pens.

EXPERIMENTAL. Leishmania donovani, which causes kala azar in human beings, does not develop in . avi n '. T osoma cruzi undergoes development in this tick-in the Iaboratory. _. evansi cannot be transmitted from the tick to animals except by inocula. tion of a suspension of infected ticks.

Experiments on transmission of heartwater Cliickettsia ruminan. tium) of cattle by means of Q. swig have been unsuccess .

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