Open Access

Hideo Ishijima

• Fly larvae of the Anthomyiidae, Muscidae, Calliphoridae, and Sarcophagidae are scavengers and breed in filthy material such as animal dung, human feces, dead animals and decaying vegetables. Therefore, the presence of these larvae in our environment indicates defective sanitary conditions, and offers many problems from the standpoint of public health. Clinically, the larvae of some species cause myiasis in man and animals. On the other hand, in the field of legal medicine postmortem time of dead bodies is estimated in some cases by the species and age of larvae collected from them. Thus, the fly larvae are closely associated with our lives. Morphologic studies on larval stages of flies were started in the beginning of this century by Portchinsky (1910), Banks (1912), MacGregor (1914), and Keilin (1915 and 1917). Portchinsky first described chiefly the habits and metamorphosis, and later MacGregor emphasized structure of posterior spiracles in the identification of the larvae. Keilin (1917) discovered and emphasized the importance of the characteristic structures such as the cephalopharyngeal sclerite, anterior and posterior spiracles and other external and internal characters. Following them, many authors made comparative and systematic studies of fly larvae and there are many reports of such research. However, morphology, taxonomy and ecology of these fly larvae have not been studied systematically in Japan. During the period from 1915 to 1936, 10 or more accounts were made about fly larvae that caused intestinal myiasis in man. In 1937, Kodama and Yasuda reported Ophyra nigra Wied. asa cause of intestinal myiasis. Yasuda (1939) reported 12 species of fly larvae in Seoul, Korea with detailed drawings and descriptions. Lopes (1943 and 1946) reported sarcophagid larvae from Neotropical region. Hall (1947) described calliphorid larvae from North America in his publication "The blow flies of North America". In 1951, Roback used the characters of the larvae such as pharyngeal sclerites and posterior spiracles for the classification of the Calypterate, Diptera. In the same year, Zimin reported Russian muscoicllarvae in his publication "Fauna USSR, Muscidae" using the external characters such as spines, papillae, and anal plate on the body surface as well as anterior and posterior spiracles and cepahlopharyngeal sclerite. Fan (1957) reported some filth fly larvae from China. In Japan, Kana et a!. (1950-1958) described larvae of 39 species belonging to 4 families. In the present paper, the author describes 3rd stage larvae belonging to 70 species in 33 genera of 4 families. In addition, photographs of internal and external structures and keys to families and species of 3rd stage larvae are given. Moreover, 6 species belonging to Muscidae and 1 species ofSarcophagidae for which the larvae were not seen are cited from the descriptions and figures published by Keilin (1917), Zimin (1951), Kano and Sato (1951), and Fan (1957). Those species are also included in the keys of this paper.