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Volucella thompsoni n.sp. is described and illustrated. The following characters distinguish it from the other species of the Volucella pellucens group: 1) abdominal tergite 2 longer than tergite 3, or at most 2.4x wider than long; 2) male basoflagellomere in lateral view slightly constricted in middle; and 3) surstylus greatly shortened in lateral view. This species was erroneously named as V. matsumurai Han et Choi replacing V. pellucens var. japonica Matsumura for homonymy. Subsequent examination of the holotype of V. pellucens var. japonica revealed that it was merely a variant of V. pellucens tabanoides Motschulsky. In addition, we compared V. thompsoni n.sp. with the other known species and subspecies of the pellucens species group (V. inflata, V. nigricans, V. pellucens pellucens and V. pellucens tabanoides). For V. pellucens, we discussed the status of the Asian and European populations, and provided a justification for recognizing them as two subspecies. We also provided a key and diagnoses for the included species with the detailed illustrations of their male genitalia and other body parts.

Japanese species of the genus Platycheirus Lepeletier and Serville, 11 species in all, are treated. Three new species, P. subcomplicatus, P. pennipes and P. immaczdatus are described and figured. P. peltatus, P. complicatus, P. clypeatus, P. perpallidus and P. dux are recorded from Japan for the first time.

Two species of the genus Platycheirus, I? ovalis Becker and P. angustatus (Zetterstedt), are redescribed. P ovalis Becker is recorded from Japan for the first time. P. subcomplicatus ohara, 1980 and Melanostoma alpinum Shiraki et Edashige,l953 are synonymized with P. latimanus (Wahlberg, 1844) and P. urakawensis (Matsumura, 1919), respectively.