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2 Iolmi Rousettus aegy%iacus June (CNIM)

4 Katire *I'IimeteIIus ‘Inn one 1 Sep

9 Sunat Taphozous Erforatus haedinus Feb DISTRIBUTION IN THE SUDAN

Northern: One larva from an undetermined species of bat at DongoIa, I2 April 1917, Bedford legit; Sudan Government collections.

Khartoum: Several larvae from an undetermined species of bat (s?) at Khartoum, 20 September 1911., R. Cottam le it; in Sudan Government collections, one retained in Hoogstraal col ection.


The Ar as ves rtilionis group, consisting of A. ves rtilionis (Iatreille, 18 in urope and Africa, A. Eillus Kohls, I955, on Palwan Island in the Philippines, and of-numerous closely related forms of yet uncertain species status, ranges throughout the conti. nents and island groups of the world, except in the Americas. It is possible that certain African populations presently identified as 1_\. ves%rtilionis will prove to be separate, closely related species. fuller study of this group is under way.

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Eventually, the round bat.argas most likely will be found in many more territories of Africa.


*Field identification of host; specimen not seen by a specialist in bat taxononw.

N(RTH AFRICA: EGYPT (As 5. fischeri: Audouin 1826, Savigny 1827,E"F"“£- V01p erre and Riek 1955""H". oogstraal 19521). TUNISIA (Colas.Belcour 1933B).

WEST AFRICA: FRENCH WEST AFRICA: Although reported as A.

ves rtilionis By Marchoux and Couvy (l9l2A,B,l913A,B), there-is some IIkeIiEod that some or all of these specimens may have been those subsequently used as the types of 5. boueti. Rousselot

(195312). 00111 c0As'r (Simpson 1911.).

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sournmm AFRICA: ANGOLA (larvae from Dundo, Lunda, north. ess~te'rh'Tnge1'e_, elm). MOZAMBIQUE ("'Brumpt's Precis"). sournnzrm anwrsm (Jack 1932. Bedford 1934).

UNION OF SOUTH AFRICA: South African adults described and illustrated by Nuttall et al (1908) as A. ves rtilionis represent A. confusus. Howard (@187, white (19'I0B~ o 3213,1931.) _a'.1so cofiused these two species as probably also did Cooley (1934); cf. Hoogstraal (19553, p. 586) for details. Dr. 0. Theiler has sent a female a.nd nymph of 5. ves rtilionis from Pretoria and Grahamstown. These were among larger numbers of 5. confusus and A. boueti. No specimens of A. ves rtilionis were inclfided with '1I1ateri"a7_I of A. confusus and A. ueti rom collections of the South Africa!-1 Institute for Yiedical Research, recently sent for identification by Dr. F. Zumpt. These observations lead one to suspect that 5. vespgrtilionis may be less common in South Africa than 5. confusus.


OTHER AREAS: Available naterial referable to this group is from Englaa, Netherlands, Sweden, Spain, Germany, Korea, China, Philippines, and Ceylon. The group is also known to occur in southern India, Cambodia, Australia, France, Italy, and Russia. Differences between African and European specimens and those from Australia and Asian areas are very slight indeed.

HOSTS (Africa)


Almost any bat, whether it lives in large colonies or in small

groups, may be parasitized by A. ves rtilionis. All stages prob. ably infest the same kinds of hosts.

Three species of chiropteran hosts are thus far known from the Sudan (records above). The Angolan larva is from Pifiistrellus

nanus. In Egypt, we find larvae chiefly on Otonypteris . empgichi,

Rhino ma hardwickei cystops and R. microphyllum, ap iaus p. per ora us and T. nudiventris, N cteris . e ‘ca, T§dar1da_§. III T


ae tiaca and T. teniotis ruppe '. hey are less numerous on Rhinolophus clivosus Erach natus, R. mehel ', Asellia t. triedens, Plecotus auritus christiei, Pi istrellus E. §uhIi, and Rousettus a. aeifytiacus. zigyptian bats reviewed by Sanborn and Hoogstraal

T1955 .



Nymphs and adults on several occasions have attacked us in caves and we easily induce it to bite ourselves in the laboratory (Hoogstraal l952A,l955B).


Life Cycle

In our laboratory, Mr. Sobh Gaber successfully rears spec. imens of_A. ves rtilionis at SOKF. to 90°F. an 40% R.H. to 5C% R.H. Egg batches consist of thirty to fifty eggs, one.fifth or one.sixth of which usually do not hatch. Larvae emerge from sixteen to twenty days after the eggs are laid and some will feed as quickly as four days afterwards. The duration of larval feed. ing varies from fourteen to 31 days, but is usually seventeen to nineteen days. Five to ten days later larvae molt to nymphs, which are capable of feeding three or four days after this and after subsequent molts. Usually two feedings are indulged by

nymphs, followed by a molt eight or nine days after the first meal and twelve to fourteen days after the second meal. Nymphs

become replete in from twenty to fifty minutes, usually in thirty to forty minutes. Males may emerge from the first nymphal molt, but usually nymphs molt twice before becoming adults. Males and females may feed within seven days after melting. Duration of adult feeding is thirty or forty minutes. No female has ovi. posited within six months after the molt, even though she has been with a male continuously and both have had two to six blood meals. The first egg batch follows a blood meal by about a week. The first oviposition appears to trigger a physiological release mechanism for, in several instances, three months after. wards females have deposited a fertile egg batch with or without a meal. We are at present attempting to ascertain whether the long interval between melting and oviposition is peculiar to

these laboratory observations or whether it is a usual feature

in our local populations.

A. ves rtilionis is more lethargic than A. boueti. Adults, if undisturggd wHIIe imbibing from a vein in the wing membrane of a bat, may remain attached for as long as five hours after engorgement is apparently completed. The feeding tick remains motionless with all legs down but, when fully distended without release of mouthparts from the host skin, it usually raises the fore legs to an antennalike position. During engorgement the beak is disengaged from the host skin only after considerable disturbance.

Large blood clots form at the site of the bite, both on the bat's body and in the wing membrane. This phenomenon, on bats, is in marked contrast to that observed by Lavoipierre and Risk (1955), using ticks from our collections, and laboratory rodents. The greater avidity with which these ticks attack bats probably accounts for the more conspicuous sequelae in these animals.

larvae may be found anywhere on the body or wing membranes, but most commonly at the edge of the hairy parts, seldom on the head, feet, tail, or trailing edge of the wings.


European and African populations of this tick, which thus far cannot be morphologically differentiated, withstad a wide

range of temperature and humidity conditions. Host flight habits account for the wide distribution of A. ves rtilionis, but we

are not aware that host migration is‘; factor In mixing populations from widely differing ecological situations.

European and South African populations exist under temperate climatic conditions with pronounced seasonal changes and with moderate to heavy rainfall. Those of Egypt and of northern Sudan normally tolerate the most extreme arid niches in which any arthro. pod is known to survive. Their engorged larvae, however, are found usually among moist dung or in dung between crevices of bats‘ retreats. Just where females commonly oviposit in nature and where unengorged larvae rest before seeking a host has not yet been satisfactorily determined

Throughout Europe and Africa interstices in the walls of bat. infested caves and buildings are the most common habitats of_§. ves rtilionis. They may also be found in tree holes and in other situations frequented by certain bats. In Cairo a specimen, recalling Robert Burns' wee louse, has been taken from a worshipper during church service by an observant but distracted friend sit. ting behind. In Iraq, Patton (1920) reported the same or a closely related species in Bedouin tents in which bats presumably rested by


Egyptian specimens hide alone or clustered in large or small groups usually well concealed between shale or in crevices of walls. Some individuals are observed wandering openly on the walls. Unconcealed individuals are noted much more frequently in those caves or niches that only erratically harbor a few bats than in large caves where many bats usually roost. Possibly our entry into caves infrequently visited by any animals induces these ticks to investigate the possibility of a meal.

Small nubers of the round bat_argas frequently are found in niches in the most unexpected cliffsides where a few old pellets

of dung indicate that hermit bats such as Oton cteris Q. hemprichi occasionally spend the day. These ticks lead a most uncertain existence and often wait months on end for a host, as revealed

by their compressed bodies and by the age and scarcity of hosts‘

dung in these places.

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