Hiraku Yoshitake

Evolution of host utilization patterns in the seed beetle genus Mimosestes Bridwell (Coleoptera: Chrysomelidae: Bruchinae).

The evolutionary history of diet breadth expansion and intergeneric host shifts in the seed beetle genus Mimosestes were reconstructed to investigate the process of host range expansion in phytophagous insects. The evolutionary correlation between diet breadth and variation in oviposition behavior of Mimosestes was also examined to estimate the process of generalist evolution within the genus. Ancestral state reconstruction based on a molecular phylogeny inferred from three mitochondrial markers (16S rRNA, 12S rRNA, and COI) and one nuclear marker (EF-1alpha) revealed that host utilization patterns were shaped by repeated colonizations to novel or pre-adapted host plants. Neither plant genus and species group level host conservatism nor an evolutionary tendency toward specialization was found in the genus, contrary to the expectations of plant-insect co-evolutionary theory. In addition, statistical analyses revealed that diet breadth was significantly correlated with oviposition behavior, suggesting that behavioral factors such as the oviposition preferences of female seed beetles affect the expansion of diet breadth in generalists.

Herbivore pressure by weevils associated with flower color polymorphism in Geranium thunbergii (Geraniaceae)

Although floral herbivory has recently received increased attention as an important factor influencing plant reproduction, relatively little is known about how its frequency and intensity vary depending on traits of host plants. Here we report that herbivore pressure by a weevil, Zacladus geranii, is associated with a flower color polymorphism of Geranium thunbergii (Geraniaceae). Pink and white flower color morphs have been reported in G. thunbergii, and we found in a three-year field survey in multiple populations that, generally, adult weevils more preferentially visited white flowers than pink flowers. Consistently, we found more severe damage by weevil larvae in white flowers. Overall herbivore pressure for G. thunbergii varied strongly between populations, and the difference seems to be partly explained by the co-occurrence of a related plant species, Geranium yezoense, in a population, as weevils preferred it to both color morphs of G. thunbergii, thereby relaxing overall herbivore pressure for G. thunbergii. Nonetheless, despite such high variability, the preference of weevils for white morphs over pink morphs of G. thunbergii was found across multiple populations. We discuss possible mechanisms causing the association between flower color and herbivore preference as well as its evolutionary consequences.

Phylogenetic Position of the Genus Wagnerinus Korotyaev (Coleoptera: Curculionidae) Associated with Galls Induced by Asphondylia baca Monzen (Diptera: Cecidomyiidae)

Based on molecular phylogenetic analysis using three regions of mitochondrial DNA, we investigated the phylogenetic position of the genus Wagnerinus (Curculionidae: Ceutorhynchinae), which includes a species that feeds obligatorily on galls induced by Asphondylia baca (Cecidomyiidae) on the axillary buds of Weigela species (Caprifoliaceae). Although Wagnerinus has been placed in either Ceutorhynchini or Scleropterini, the phylogenetic relationships inferred from the molecular data suggest that neither Ceutorhynchini nor Scleropterini are monophyletic, and Wagnerinus is separated from the other genera placed in the two tribes.

Taxonomic Study of the East Palaearctic Genus Cardipennis Korotyaev (Coleoptera: Curculionidae: Ceutorhynchinae)

ABSTRACT The genus Cardipennis Korotyaev, 1980 (Ceutorhynchinae: Ceutorhynchini) was studied on the basis of detailed morphological observations of various materials. Different scale patterns within a species are found for all the three species. Based on the external morphology and genitalia characteristics, Cardipennis rubripes (Hustache, 1916), C. sulcithorax (Hustache, 1916), and C. shaowuensis (Voss, 1958) are redescribed, with new records of C. rubripes from mainland China. Cardipennis species are mainly associated with annual herbs of Cannabis and Humulus (Cannabaceae). A key to species, habitus photographs, and illustrations of important characters are provided for each species. Distribution maps of the three species are also given.

Macrocyrtus imomzodai Barševskis, 2016, a new synonym of Metapocyrtus ( Orthocyrtus ) orbiferoides Schultze, 1918 (Coleoptera: Curculionidae: Entiminae)

Metapocyrtus (Orthocyrtus) orbiferoides Schultze, 1918 was described based on the female holotype collected from Ilocos Norte, North Luzon, Philippines. Since that time, it has been left unstudied for almost a century until I examined the holotype of M. (O.) orbiferoides in 2010 at Senckenberg Naturhistorische Sammlungen, Museum für Tierkunde, Dresden (SMTD). Recently, Barševskis (2016) described Macrocyrtus imomzodai based on two female specimens from Ilocos Norte, Luzon. Judging from the original description and dorsal and lateral habitus images, it is quite apparent that M. imomzodai is conspecific with M. (O.) orbiferoides. Here I propose a new synonymy based on these examinations. I thank Klaus-Dieter Klass, Olaf Jäger, Christian Schmidt, and Matthias Nuss (SMTD) for their support during my stay in Dresden. My thanks are also due to Steve R. Davis (American Natural History Museum, New York) and Naoko Nakahara (Tsukuba) for their help for preparing the manuscript.

Taxonomic revision of the East Asian genus Scleropteroides Colonnelli, 1979 (Coleoptera, Curculionidae, Ceutorhynchinae)

Abstract The genus Scleropteroides Colonnelli, 1979 (Ceutorhynchinae: Scleropterini) was revised on the basis of detailed morphological observations. The genus was redefined to include three species from East Asia: S. hypocrita (Hustache, 1916) is redescribed and recorded from northeastern China and northern Korea for the first time; S. horridulus (Voss, 1958) is redescribed with new records from southern Korea; S. insularis Voss, 1971 was moved from synonymy with S. hypocrita to that with S. horridulus (syn. n.), and S. longiprocessus Huang & Yoshitake, sp. n. is described as new, sympatric with S. hypocrita in Japan. All the species are associated with woody Rubus species (Rosaceae). A key to species, habitus photographs, illustrations of important characters, and distribution maps are provided for each species.

Taxonomic review of the Genus Rhinoncomimus (Coleoptera: Curculionidae: Ceutorhynchinae) with description of a new species from Yunnan, China.

The genus Rhinoncomimus Wagner, 1940 includes seven species from Eastern Asia. One new species, Rh. continuus sp. nov. from Yunnan, China, is described. Habitus photos, illustrations and descriptions of all species except Rh. rubripes Korotyaev, 2006 (a possible junior synonym of R. niger Chûjô and Morimoto, 1959) are provided in detail, as well as key to species and distribution maps. In addition, the host plant of the type species Rh. klapperichi Wagner, 1940, Polygonum hydropiper L. (Polygonaceae) is newly recorded.