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SOUTHERN AFRICA: SOUTHERN RHGJESIA, BASUTOLAND, and EECHUANA. LAND ~ogs raa 512). umou or sourm AFRICA [For details con. cerning A. confusus reported as A. ves rtilionis by Nuttall et al (1908), I!bw_'_(“<¥58ard 1 ), and Bedford ‘('§§1 423", snd""Fr more rs¢snt_r§. ords, see Hoogstraal (l955B). Subsequently, Dr. Zumpt has sent additional specimens from Bloemfontein, Orange Free State, and from Lady Frere, Cape Province 7

HOSTS

At the present time we have definite evidence of larval A. confusus from only a few species of insectivorous bats; Chaerephon

in

mayor and Ta hozous Erforatus haedinus (Equatoria recor s a ve ;

ques ionab y host fie d etermi nations not checked by a specialist) from Eptesicus Eillus and Pach otus sp. (Equatoria records above);

and from E tesicus cagnsis, ach otus sp. Minio erus natalensis arenarius, Taphozous _p. perforatus, __T. (L.) n iven ris, Dtonycteris

H. hem ichi N cteris t. thebaica a.nd Tadarida a. ae tiaca -(floogstraal 195§B). NyTnphs and Eults found in bauiiested caves and buildings probably feed on the same species of hosts as do larvae.

The record of A. confusus (= A. ves rtilionis) attacking pen. guins in Queenstown, Cape Colony (NuttalE et aI T9158) must be re.

garded as questionable (Hoogstraal 1955B)._

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A. confusus has been reared in our laboratory at temperatures between 3%‘. and 90°F. and at relative humidities between 1.0% and 50%. A single egg batch consists of from forty to seventy eggs with fifty to sixty the most common quantity. Eggs hatch from 21 to 25 days after being laid. Larvae have commnenced feeding five to 26 days after hatching. The duration of larval feeding varies from five to fifty days but most larvae drop from the host in two or three weeks. Afterwards, larvae remain quiet for seven to twelve days before the nymphal molt.

Four nymphal instars are invariable in our nuerous observa. tions. Nymphs, like adults, feed for from 25 to fifty minutes. The first nymphal instar, however, never feeds; it melts to the second instar usually in ten to thirteen days (range eight to 21 days). One to three weeks later the second instar nymph feeds an molts to the third instar some two weeks later (range eight to 23 days). The third instar nymph takes food between three and 35 days afterwards and molts three or four weeks later (range fifteen to 59 days). The fourth instar nymph feeds between five and 36 days afterwards and molts to the adult stage three or four weeks later (range seventeen to forty days).

Note that although there are many morphological similarities between.A. confusus and A. boueti, the biology of the nymphal stage of each is distinc .

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In this species, the observed period between nymphal melting and feeding is quite variable. Some accept food within five to seven days although two to three weeks, or longer, is more common for this and for other bat.parasitizing argasids. Also noteworthy is (1) the average two week postfeeding period of second instar nymphs in contrast to the three or four week average postfeeding period of the two subsequent instars, and (2) the nonfeeding first instar.

Adults placed together shortly after molting have been observed to mate only after feeding which may occu from eight to sixteen days after melting. The feeding period varies from forty minutes to two hours. No egg batches have been deposited before three and a half to four months after melting. Further studies on the F1 generation are in progress.

Ecology

We have collected, with considerable and strenuous effort,several hundred specimens of A. confusus in Egypt. This species, together with A. transrariepihus, is the most secretive of bat in. festing argasids.-_Tt_§edgE§_it§elf deeply into the narrowest crevices of caves and of hillside crannies in which bats rest.

It is never found easily or in groups of more than two to a max. imum of twelve specimens. We know of only a single exceedingly small population in Cairo, where bats roost in buildings that are more humid than desert caves. In the environs of Cairo, A.

confusus is scattered throughout desert and desert.edge retreats, EII arid, such as antiquities structures, caves, and hillside crannies.

Records from northern Sudan and from the Protectorates of South Africa indicate a more or less similar tolerance of aridity, but those from various regions of South Africa, Torit, and the crater of Mt. Menengai in Kenya indicate also that certain popu. lations exist in markedly humid environments where they tolerate lower temperatues and higher relative huidity than they do in

Egypt.

DISEASE RELATIONS

RNTS: A small number of specimens thus far studied in NAMRU.3 laboratories have been negative for blood protozoa, spirochetes, viruses and rickettsiae, and Shigella organisms.

REMARKS

Further stuies on the habits ad ecology of this species are presently under way and will be reported when completed. For a definition of the subgenus Chiro terar as and for criteria to dis. tinguish this species from A. boueti, see page 95.

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IDENTIFICATION

A. confusus adults have an extremely wide body outline, ad, in common witR_§. boueti, are characterized by the absence of a sutual line dividing dorsal and ventral surfaces, and by the pres. ence of a conspicuous hood over the mouthparts. In A. confusus the dorsal integumental potuberances are fine, shin§.tIpped:__ tapering points which on the lateral margin are more closely spaced and more regular. The posterior discs are arranged radially; the legs are shorter than the body length; and the hypostome has only a single pair of denticle files. The tarsi have no dqrsal protu. berances. A pair of grooved organs of unknown function is present just posterior of the anus on the ventral surface.

Except when greatly engorged, the peripheral flange of the body remains partly unfilled. In partially engorged individuals this flange is flat, and in dry specimens it my be turned up like a rim. The body color is reddish yellow with a central, darker area of varying extent.

Males measure from 5.9 mm. to 6.4 mm. long, and from 7.4 mm. to 7.3 mm. wide (average 6.1 mm. long and 7.5 mm. wide). The genital aperture forms a wide arc. Females are larger, and measure up to 8.0 mm. long and 9.5 mm. wide. The female genital aperture is a transverse groove with thick, rugose lips.

The n h and larva have been described by Hoogstraal (19553). The larva first instar nymph are quite similar to those of A. boueti but the successive instars of each resemble the associated

REE’.

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