Carl J. Mitchell

Nesting Activity of the House Sparrow in Hale County, Texas, During 1968

Nestling House Sparrows, Passer domesticus, are involved in the amplification of western encephalitis (WE) virus activity in Hale County, Texas, during the epidemic season (Hayes et al., 1961 \ Holden et al, 1973a). Experimental studies (Holden et al., 1973b) have shown that nestlings of this species are admirably suited for this role since they may circulate virus in the bloodstream for several days at concentrations sufficient for infecting vector mosquitoes. Information on the nesting activity and reproductive capacity of the House Sparrow in Hale County is requisite to an understanding of the seasonal dynamics of WE virus activity in the area; therefore, the present study was undertaken.

New Host And Distribution Records Of Acarina (Myobiidae, Sarcoptidae, Teinocoptidae) From India

In the course of studies on the ecology of ectoparasites of mammals in Calcutta, India and environs during 1964–1965, collection records were obtained for 3 species of mites which help clarify certain problems concerning the host relationships and geographic distribution patterns of these species. These records are reported here. All of the specimens of Acarina listed below have been deposited in the collection of the B. P. Bishop Museum, Honolulu, Hawaii.

Biological Studies On Laelaps Myonyssognathus G. & N. (Acarina: Laelapidae)

Laelaps Myonyssognathus Grochovskaya & Nguyen, 1961, was studied in the laboratory at 80% and 90% RH and 30°C (±2°). The life history stages and their approximate duration follow: egg, 1–1.5 days; larva, 9–21 hr; protonymph, 2–9 days; deutonymph, 2–14 days; adult male and adult female, maximum of 75 days. The female usually gives birth to active larvae; however, eggs are occasionally laid. The female readily mates, but may also produce progeny parthenogenetically. The offspring of virgin females were all males. Molting and mating behavior are discussed briefly. The most progeny produced by a single female was 12. An increase from 80% to 90% rh significantly lowered the larval mortality rate. The larva is the active stage most susceptible to desiccation. The larva does not feed before molting. All other active stages readily feed on blood, but apparently cannot penetrate the unbroken skin of their host. Cannibalism of larvae by their mothers was observed rarely. L. myonyssognathus responds positively to human breath and artificially generated CO2, but not to human breath which has had the CO2 removed. The odor of blood also elicits a positive response. The biology of L. myonyssognathus is compared with that of related laelapines, and the significance of behavioral patterns is discussed.

Taxonomy, distribution, and host associations of Laelaps myonyssognathus Grochovskaya and Nguyen (Acarina: Laelapidae).

All active life history stages of Laelaps Myonyssognathus Grochovskaya & Nguyen, 1961, are described and illustrated. Laelaps (Laelaps) prognathus Jameson, 1965, is considered to be a junior synonym of L. myonyssognathus . Abo, the specimen referred to as Haemolaelaps sp. by Pippin & Shimada (1966), collected from Rattus norvegicus on Iwo Jima, Volcano Is., is considered to be L. myonyssognathus. New host and locality records follow: ex R. rattus mindanensis , Pampanga, Luzon, Philippine Is.; ex Suncus sp., Baratpur, Rajasthan, India; ex Bandicota sp., Kolar District, Mysore, India; ex Mus musculus homourus and Suncus stoliczkanus , Kanha Park, Madhya Pradesh, India; ex Suncus murinus , Ratanpur, Hoogly District, W. Bengal, India; and ex Suncus murinus, Bandicota indica, Bandicota bengalensis , and Rattus rattus , Calcutta, India. Taxonomic relationships, geographic distribution, and host associations of L. myonyssognathus are discussed briefly.