Hiroto Nakayama

Discovery of a new species of the genus Borophaga Enderlein from Japan (Diptera : Phoridae)

Japanese species of the genus Borophaga are revised. Borophaga clandestina sp. nov. is described, and brief description of a known Japanese species, B. femorata (Meigen), is added. Borophaga clandestina sp. nov. is similar to B. femorata in general appearance, but they are clearly distinguishable in genitalic characters. The aedeagus of Borophaga is a complicated structure composed of multiple sclerites, and completely different from the simple, tube‐shaped aedeagus in Stichillus or Peromitra, members of the Stichillus subgroup. The state of the left flattened arm derived from the posterodorsal margin of the hypandrium being broadened at the base could be synapomorphic to the Borophaga subgroup comprising Borophaga, Godavaria, Latiborophaga, Antipodiphora and Abaristophora.

Systematic and morphological studies of the genus Chaetopleurophora Schmitz (Diptera: Phoridae) occurring in Japan

Japanese species of the genus Chaetopleurophora are reviewed. All belong to the C. erythronota group. The following three species from Japan are described: C. rhomboidea sp. nov., C. pygidialis Schmitz and C. dividua sp. nov. The male and female genitalia are studied and further examples of unique characters of the genus including asymmetric features are added. The male aedeagus of the genus is illustrated for the first time. The aedeagus of the species treated in this study consists of only two components, the inner core plate and the outer jacket plate. The jacket plate wraps sinistrally around the core plate. The combination of the core plate and the jacket plate forms complex, asymmetric features of the aedeagus in the Phoridae. The structure around the genital opening in the female genitalia protrudes posteriorly under the segment IX + X, and shows asymmetric features in C. rhomboidea sp. nov. with a bilaterally different degree of sclerotization, shifted genital opening to the right side and a membranous ribbon just on the left side. In addition, C. dividua sp. nov. is different from most of the species in the C. erythronota group, and very closely related to C. multiseriata (known in North America) in the male and female genitalia, wing venation and bristle formation on the scutellum. It is suggested that C. dividua sp. nov. forms a monophyletic group with C. multiseriata and the related species.

Abaristophora sachalinensis Michailovskaya (Diptera: Phoridae) representing genitalic affinities with the genus Borophaga Enderlein

Abaristophora sachalinensis Michailovskaya is reviewed based on Japanese materials. Its male genitalia are compared with those of the genus Borophaga, which is a genus in a group of the related genera, the Borophaga subgroup. A synapomorphic character of the Borophaga subgroup including Abaristophora, the left flattened arm derived from the posterodorsal margin of the hypandrium being broadened at the base, is confirmed in A. sachalinensis. Morphology of the aedeagus in A. sachalinensis is complex and extremely asymmetric, and very similar to that of species of the genus Borophaga, but the characters observed in this study are not regarded as synapomorphic for the Borophaga subgroup.

Revision of the genus Stichillus Enderlein of Japan (Diptera : Phoridae)

The genus Stichillus in Japan is revised. Three species are recognized: S. japonicus (Matsumura), S. spinosus Liu and Chou and S. cylindratus sp. nov. Stichillus brunneicornis Beyer is excluded from the Japanese fauna. These Japanese species are described and keyed. The male genitalia and the female terminalia are illustrated. Some unique characters of the male genitalia in the genus are reported, and morphology of the male genitalia and the female terminalia is discussed.

Complex asymmetric male genitalia of Anevrina Lioy (Diptera: Phoridae)

Detailed structure of the male genitalia of Anevrina is described. Hitherto unknown morphological characters of the internal sclerites relating to the epandrium and hypandrium are illustrated and elucidated. The subepandrial sclerite + bacilliform sclerites are distinctly modified, and the typical subepandrial sclerite is not recognizable. The right base of the medially shifted right surstylus is not connected to the posterior margin of the epandrium, and is directly supported by a robust bacilliform sclerite. The robust bacilliform sclerites are greatly developed inside the epandrium, and extended to three clasping components, the left surstylus, the medially shifted right surstylus and a pair of clasping lobes on the posteroventral margin of the right side of the epandrium. The upper lobe of a pair of clasping lobes on the right side of the epandrium is considered to originally have been situated on the left side and subsequently shifted to the right side. The plesiomorphic state of the clasping components relative to Anevrina is thought to be symmetrically four, comprising both the left and right surstyli and the posterior edge of both sides of the epandrium, indicating that the amazing phenomenon of cross-shifting of the clasping components has occurred in Anevrina. A cladogram generated based on the genitalic characters observed in this study shows sister groups within Anevrina, namely an Anevrina urbana-group comprised of A. urbana, A. setigera, A. olympiae, A. variabilis, A. thoracica, and an Anevrina unispinosa-group comprised of A. unispinosa, A. curvinervis, A. luggeri and A. macateei.

Systematic and morphological evaluations of a new species of Kuenburgia Schmitz (Diptera: Phoridae) with remarkable asymmetry of the male genitalia, including a bifurcated left surstylus

The monotypic genus Kuenburgia is revised, with description of a second species, K. bifurcata sp. nov., based on both sexes from Japan, and redescription of the type species, K. vidua, based on additional Japanese females. Kuenburgia bifurcata sp. nov. more closely fits the characters of Kuenburgia as represented by K. vidua than those of any other genera. The male genitalia of K. bifurcata sp. nov. lack the right surstylus, a character shared with the genus Trispiniphora, indicating a close relationship between these genera. The left surstylus of K. bifurcata sp. nov. is bifurcated and functions as a clasping device, balancing itself in a complex fashion with the right side of the epandrium and the left and right lobes of the hypandrium, and compensates for the loss of the right surstylus. The inner wall of the bifurcated left surstylus is well developed and also bifurcates along the left and right tines. It is considered to be homologous with the subepandrial sclerite + bacilliform sclerite in Eremoneura. The aedeagus of the male genitalia is composed of an inner core plate and an outer jacket plate, with the outer jacket plate wrapping in a sinistral fashion around the inner core plate.

New host record for three scuttle flies, Megaselia flava, M. kanekoi and M. gotoi (Diptera: Phoridae), on the poisonous fungus Amanita ibotengutake (Agaricales: Amanitaceae)

We identified three species of fungivorous scuttle fly –Megaselia flava, M. kanekoi and M. gotoi– from eight fruit bodies of a fungus, Amanita ibotengutake, which has not previously been recorded as the host of these flies.