Setal counts and measurements of the sorghum midge and its relatives in Japan

Abstract

At least 10 species of the genus Contarinia have been known to exist in Japan (YUKAWA, 1971; YUKAWA, unpublished), and about a hundred nominal species have been recognized in the world. They are quite similar, and species identifications are mainly based on host data. In recent years, a successful attempt to separate fourteen species of Contarinia was made chiefly by counting thoracic setae and by measuring antennal segments (HARRIS, 1966). In order to identify the sorghum midge, Contarinia sorghicola (COQUILLETT, 1899) in Japan and to separate it from two unnamed relatives whose larvae develop in the spikelets of Triticum aestivum L. and Echinochloa crusgalli P. BEAUV., respectively, the antennal segments, wings and ovipositor of these species were measured and the numbers of their eye bridge-ommatidia, fronto-clypeal setae and mesepimeral setae were counted. As a result, the similarities and dissimilarities in morphological characteristics among these three species were clarified by using a wide spectrum of the characteristics examined.