Wohlfahrtia magnifica - Wohlfahrt's Wound Myiasis fly
Wohlfahrtia magnifica is an obligate larval parasite of living, warm-blooded vertebrates and never develops in carcasses or other decaying organic matter. The ecology and population dynamics of this species are poorly known. The adults are active from May to October (Hadani et al. 1971; Ruiz Martinez and Mira 1994; Farkas et al. 1997) but are most numerous in the hot summer months. The flies are diurnal, favouring the sunny and hot hours of the middle part of the day: they are seldom seen in cool, dull weather. They rarely enter houses. Even where there is a high incidence of wohlfahrtiosis, only a relatively small number of adults can be found around grazing animals (Hadani et al. 1971; Hall et al. 1995; Farkas et al. 1997). The females are flower feeders until they become sexually mature.
Females are larviparous and carry an average of about 80 larvae, never more than 120 (Ruiz Martinez et al. 1997). They deposit first instar larvae at sites of wounding on the host or beside its body orifices, where larval development is very rapid. The larvae moult to second instars within 6-8 hours, and then undergo a second moult to third instars. Although a humoral immune response of sheep to wohlfahrtiosis has been detected (Farkas et al. 1998), it is not known whether or not this response can influence larval growth and survival. Fully grown larvae leave the wound 5-7 days after larviposition and pupate in the soil (Portschinsky 1916; Hadani et al. 1971). Entry into diapause depends on decreasing daylength and temperature (Ternovoy 1978). The species overwinters in the pupal phase in the soil, adult flies emerging in the following spring, when the soil warms and the days lengthen.
Based both on catches of adults and on infestations in animals and humans, Wohlfahrtia magnifica is widely distributed throughout the warmer, southern parts of the Palaearctic region, from the Mediterranean basin, through central and eastern Europe to northern Asia. It occurs in Spain (Ruiz Martinez et al. 1987), France, Italy, Hungary (Farkas et al. 1997), Slovakia, Romania (Lehrer et al. 1988), the former Yugoslavia, Bulgaria, the former USSR, Egypt, Israel (Hadani et al. 1971), Iran (Janbakhsh et al. 1976), Turkey and Mongolia (Valentin et al. 1997).
Farkas, R., Hall, M. J. R. and Kelemen, F. (1997). Wound myiasis of sheep in Hungary. Vet. Parasitol. 69, 133-144.
Farkas, R., Hornok, S. and Gyurkovszky, M. (1998). Prelimimary studies on humoral immune response of sheep to wohlfahrtiosis. Vet. Parasitol. 75, 279-284.
Hadani, A., Rabinsky, R., Shimshoni, A. and Vishinsky, Y. (1971). Myiasis caused by Wohlfahrtia magnifica (Schiner) in sheep on the Golan Heights. Refuah Vet. 28, 25-33.
Hall, M. J. R., Farkas, R., Kelemen, F., Hosier, M. J. and El-Khoga, J. M. (1995). Orientation of agents of wound myiasis to hosts and artificial stimuli in Hungary. Med. Vet. Entomol. 9, 77-84.
Janbakhsh, B., Tirgari, S. and Aghamohammadi, A. (1976). Myiasis in sheep due to Wohlfahrtia magnifica (Schiner) in Iran. (Diptera: Sarcophagidae). J. Entomol. Soc. Iran 3, 7.
Lehrer, A. Z., Lehrer, M. and Verstraeten, C. (1988). Les myiases causées aux moutons de Roumanie par Wohlfahrtia magnifica (Schiner) (Diptera: Sarcophagidae). Ann. Méd. Vét. 132, 475-481. [in French]
Portschinsky, I. A. (1916). Wohlfahrtia magnifica, Schin., and allied Russian species. The biology of this fly and its importance to man and domestic animals. Mem. Bur. Entomol. Sci. Comm. Central Brd Land Administr. Agriculture, Petrograd 11, 1-108. [in Russian]
Ruiz Martinez, I. and Mira, M. C. (1994). Biogeography of screwworm fly Wohlfahrtia magnifica (Schinner, 1862) in southern Spain (Diptera: Sarcophagidae). Bol. R. Soc. Esp. Hist. Nat. (Sec. Biol.). 91, 123-128.
Ruiz Martinez, I., Cruz, S. M. D., Rodriguez, R. B., Lopez, D. M., Parra, M. S. and Navio, F. A. (1987). Myiasis caused by Wohlfahrtia magnifica in Southern Spain. Isr. J. Vet. Med. 43, 34-41.
Ruiz Martinez, I., Lopez, M. D. and Jimenez, J. M. P. (1997). Gonotrophic and embryonic development of the Palaearctic screwworm fly Wohlfahrtia magnifica. Med. Vet. Entomol. 11, 193-197.
Ternovoy, V. I. (1978). A study of the diapause in Wohlfahrtia magnifica (Diptera: Sarcophagidae). Rev. Entomol. USSR 57, 328-332.
Valentin, A., Baumann, M. P. O., Schein, E. and Bajanbileg, S. (1997). Genital myiasis (Wohlfahrtiosis) in camel herds of Mongolia. Vet. Parasitol. 73, 335-346.