Systematic position of the genus Rhaphiomidas Osten-Sacken, 1877 (Diptera, Mydidae) in the superfamily Asiloidea based on the structure of the muscles of male genitalia

摘要

There is no general agreement on the systematic position of the Rhaphiomidas in Brachycera Orthorrhapha. The musculature of the male genitalia of Rhaphiomidas hasbroucki Cazier was described and compared with that of other Asiloidea (Ovtshinnikova,1989, 1998, 2000; Ovtshinnikova, Yeates, 1998; Palmer et al., 2000). Musculature of the male genitalia in Rh. hasbroucki includes one muscle pair of the aedeagal sheath (M2), two muscle pairs of the ejaculatory complex (M30, M31), one pair of gonocoxitesmuscle (M38), one muscle pair of the proctiger (M21), one muscle pair of cerci (M29) and two pairs of tergosternal muscles M5~1 (? M5~1 + M5~3 and M5~2). The reduction processes in the aedeagal sheath muscles, in the ejaculatory complex muscles and gonocoxal muscles in Rhaphiomidas and Mydidae are very similar. The analysis of male genital muscles is not contradicting with the Yeates and Irwin's (1996) opinion, providing additional evidence in support of their view that Rhaphiomidas should be includedin the Mydidae. At least Rhaphiomidas can be considered as one of the most primitive groups of Mydidae or as a close relative to the Mydidae ancestor.