Thanatosis, also called death feigning, is often an antipredator behavior. In insects, it has been reported from species of various orders, but knowledge of this behavior in Hymenoptera is insufficient. This study examined the effects of sex, age (0 or 2 days old), temperature (18 or 25 °C), and background color (white, green, or brown) on thanatosis in the braconid parasitoid wasp .
View Article and Find Full Text PDFAn endemic subterranean Japanese carabid beetle lineage, the species group, was recently revealed to have marked regional differentiation. Studies of such features reveal insect species diversity and provide insight into the mechanisms driving species diversity. We examined specimens of this species group collected from the southern Tohoku District of Honshu, Japan, where its diversity has not yet been fully elucidated, using fine-scale field sampling and detailed comparative morphological analysis of male genitalia.
View Article and Find Full Text PDFThe ground beetle genus Pterostichus Bonelli has diversified in regions including the Far East, but taxonomic issues remain even at the species level. This study presents taxonomic and nomenclatural changes in three species of Pterostichus from the Far East: P. (Petrophilus) eximius Morawitz, P.
View Article and Find Full Text PDFNebria (Falcinebria) reflexa Bates (Carabidae), a Japanese endemic flightless ground beetle, is geographically polytypic and was thought to be composed of four subspecies (including nominotypical subspecies). Populations from Honshû recognized as three subspecies were taxonomically revised based primarily on the shape of the endophallus, a membranous inner sac everted from the aedeagus. Three known taxa, , Bates, and Nakane, are redefined based on endophallus morphology, and the latter two are described as distinct species rather than subspecies of .
View Article and Find Full Text PDFBates, 1883, a Japanese endemic genus in the subtribe Synuchina (Coleoptera, Carabidae, Sphodrini), is revised taxonomically based mainly on the shape of the endophallus, a membranous inner sac everted from the aedeagus of the male genitalia. Three known species from central Honshu, Habu, 1954; Habu, 1978; and Habu, 1978, are re-defined based on this genital character, and five new species are described from the region: Sasakawa, . .
View Article and Find Full Text PDFElucidating the basic life-history of endangered species is the first important step in the conservation of such species. This study examined the reproductive ecology and the preimaginal morphology of the endangered ground beetle Elaphrus sugai Nakane (Coleoptera: Carabidae); currently, the Watarase wetland of the central Kanto Plain, Japan is the only confirmed locality of this beetle species. Laboratory rearing of reproductive adults collected in early April revealed that females can lay more than 131 eggs.
View Article and Find Full Text PDFSadonebria Ledoux & Roux, 2005 is one of the more diverse subgenera of the genus Nebria Latreille, 1802 in East Asia, and its taxonomy remains unrevised at the subgeneric and specific levels. In this paper, two new species of this subgenus are described from Japan. Nebria quinquelobata sp.
View Article and Find Full Text PDFMany field studies of insects have focused on the adult stage alone, likely because immature stages are unknown in most insect species. Molecular species identification (e.g.
View Article and Find Full Text PDFMany parasitoid wasps learn host-associated cues and use them in subsequent host-searching behavior. This associative learning, namely "oviposition learning," has been investigated in many studies. However, few studies have compared multiple species, and no comparative study has previously been conducted on ectoparasitoid species.
View Article and Find Full Text PDFNaturwissenschaften
May 2007
The morphological characteristics of sperm and reproductive organs may offer clues as to how reproductive systems have evolved. In this paper, the morphologies of the sperm and male reproductive organs of carabid beetles in the tribe Pterostichini (Coleoptera: Carabidae) are described, and the morphological associations among characters are examined. All species form sperm bundles in which the head of the sperm was embedded in a rod-shaped structure, i.
View Article and Find Full Text PDFA phylogenetic hypothesis of the subgenus Nialoe (s. lat.) of genus Pterostichus is proposed based on a cladistic analysis of seventeen morphological characters.
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