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Sperm show marked morphological diversity, but the processes and mechanisms driving this diversity have not been fully elucidated. The beetle family Carabidae represents a potential model system for studying sperm trait evolution. In this study, sperm traits (mainly conjugation and sperm conjugate gross morphology) of 42 species from nine subfamilies of Carabidae were examined using light microscopy. Except in Harpalinae, the type of conjugation was shared by all members of a particular subfamily: in Carabinae, Elaphrinae, Patrobinae and Brachinae, sperm conjugates were observed in which variable numbers of sperm clumped together; in Nebriinae, Cicindelinae and Trechinae, sperm were not organized as conjugates but were present individually; and in Broscinae, both individual sperm and sperm conjugates were observed. In the remaining subfamily, Harpalinae, sperm conjugates were formed in most species, but a loss of conjugation was observed in some species. Mapping the observed sperm traits onto within-family molecular phylogenetic trees suggested that sperm conjugation was ancestral, with loss of conjugation evolving in several lineages. In sperm conjugates, a short spermatostyle (the axis of sperm conjugates) was the ancestral state, while a long spermatostyle evolved in subsequent lineages. In the long spermatostyle trait, the flexible type without a conspicuous 3D structure was ancestral, while the type with a conspicuous 3D structure, such as the spiral structure, evolved in derived lineages. [ABSTRACT FROM AUTHOR]

We examined the genetic divergence of Platycerus hongwonpyoi Imura & Choe, 1989 in South Korea using the nuclear wingless (Wg) gene, internal transcribed spacer (ITS) region and mitochondrial cytochrome oxidase subunit I (COI) gene. We found no variation in Wg or ITS. Based on COI, P. hongwonpyoi was split into four well defined and one weakly supported clades, which were inferred to have diverged 2.11–1.33 Ma. The Platycerus hongwonpyoi population size seems to have decreased during the past several tens of thousands of years. The divergence times of major clades of P. hongwonpyoi were comparable with those involved in the speciation of certain Japanese species. Frequent overlapping of different clades at the same sites suggests the occurrence of secondary gene flow following differentiation in South Korea. In conclusion, the genus Platycerus underwent strikingly different divergence patterns in South Korea compared with Japan according to the disparate topographies of these two geographical areas. This study aims to examine the genetic divergence of Platycerus hongwonpyoi in South Korea and compare its divergence patterns with certain speciation of Japanese species. [ABSTRACT FROM AUTHOR]

An extensive field survey was undertaken by a group of archaeologists and entomologists to discover arthropod-like petroglyphs in the center of Iran during 2017 to 2018. A remarkable motif approximately 13 × 5 cm in size was found in the Teymareh rock art site, located in Markazi province, which has yet to be reported. The single rock art distinctly represents a hexapod organism with small antenna, a streaked narrow body and a tapering abdomen. Based on distinguishing aspects of the inspected motif and morphological information of species within the class Insecta, we identified it as a jewel beetle (Coleoptera: Buprestidae). We propose that the buprestid drawing was derived from a historic artist who admired the aesthetic value of the jewel beetle. The jewel beetle's characters within Persian Plateau folklore are also briefly discussed. [ABSTRACT FROM AUTHOR]

Erotini is a small tribe of net-winged beetles known from the northern temperate zone. We investigated relationships and limits of tribes and genera using a molecular phylogeny inferred from rrnL, cox1 and nad5 mtDNA fragments. Lopheros Leconte, 1881 and Pseudaplatopterus Kleine, 1940 were inferred in current molecular analyses as terminal lineages within Erotini. Therefore, we consider Lopherotini Kazantsev, 2012 and Pseudaplatopterina Kazantsev, 2012 as junior synonyms of Erotini Leconte, 1881. The Platycis genus group comprises 19 species representing several genus-group taxa previously placed in Platycis s. l. Konoplatycis Nakane, 1969 was recovered as a deeply rooted lineage of Erotini and we inferred another independent lineage for which we propose a new genus Sinoplatycis gen. nov. Additionally, we studied the diversity of Platycis s. l. in Asia, found their highest diversity in the temperate forest habitats of Eastern Asia and inferred the paraphyletic character of the subgenus Erotides s. str. Five new species are described from China: Sinoplatycis cardinalis sp. nov., S. zhani sp. nov. (type species of Sinoplatycis gen. nov.), Erotides brunnescens sp. nov., E. pusillus sp. nov. and E. slipinskii sp. nov. The molecular phylogeny shows deep splits of Japanese species with respect to the continental Eurasian fauna and the role of shallow seas and mountain systems in the diversification of the Platycis genus group. [ABSTRACT FROM AUTHOR]

Comparison of biological characteristics between diapausing and non-diapausing strains of insects provides some insights into the mechanisms regulating diapause. In this study, biological characteristics, especially diapause characteristics and life-history traits, of a non-photoperiodic-diapause (NPD) strain of the cabbage beetle Colaphellus bowringi were compared with those of a normal, high-diapause (HD) strain that enters diapause in response to either long day length or low temperature. The NPD strain did not enter diapause at any photoperiod at 22°C or higher, but still had a capacity to enter diapause at low temperatures. Although diapause could be induced in both strains by exposure to 20°C, the proportion of individuals having shorter diapause duration was greater in the NPD strain compared to the HD strain. The NPD strain had significantly lower hatching and larval survival rates, longer developmental duration of immature stages, smaller body size and lower longevity and female fecundity compared to the HD strain. The NPD strain of this species is a promising model for investigating diapause regulation in insects in general. [ABSTRACT FROM AUTHOR]

The Japanese species of the genus Agraphydrus are revised. Five species are recognized, including Agraphydrus ogatai sp. nov. from Honshu, Shikoku and Kyushu. The new species can be distinguished by the coarse ground punctures on the pronotum and elytra, and by the shape of parameres. All species except A. luteilateralis are redescribed. All species are diagnosed, relevant morphological characters are illustrated, distributional records are summarized and an updated key is provided. [ABSTRACT FROM AUTHOR]

Allometric scaling of male horn morphologies of C opris acutidens, including the head and prothoracic horns, was analyzed. The analyses of scaling relationships indicated a discontinuous increase in head horn length and prothoracic horn height but a linear increase in prothoracic horn length relative to body size. The different results for length and height of the prothoracic horn suggest that the height is functionally more important for ensuring mates in the nests. Furthermore, both the head and prothoracic horns were dimorphic, and this characteristic was not found in the scarabaeoid beetle O nthophagus. Similarity in the switch point values for the head and prothoracic horns suggests that the dimorphism of the two kinds of horns may result from the same developmental threshold mechanism. [ABSTRACT FROM AUTHOR]

Numerous coleopteran species express male-specific 'weapon traits' that often show size variations among males, even within a single population. Many empirical studies have demonstrated that environmental conditions during development affect absolute weapon size. However, relatively few studies in horned beetles support the hypothesis that the relationship between weapon size and body size, also referred to as a 'scaling relationship' or 'static allometry', is largely determined by genetic factors. In this study, the heritability of absolute mandible length and static allometry between mandible length and body size were estimated in the stag beetle Cyclommatus metallifer. While no significant heritable variation was observed in absolute mandible length, high heritability ( h2 = 0.57 ± 0.25) was detected in the static allometry between mandible length and body size. This is the first report on the genetic effect on male mandible size in Lucanidae, suggesting that absolute mandible size is largely determined by environmental conditions while the static allometry between weapon size and body size is primarily determined by genetic factors. [ABSTRACT FROM AUTHOR]

We constructed a phylogeny of the ground beetle subgenus Nialoe ( s. lat.), genus Pterostichus (Coleoptera: Carabidae) based on two mitochondrial (cytochrome oxidase I and 16S ribosomal DNA) and one nuclear (28S ribosomal DNA) gene sequences. Thirty-three representative species of the group and three outgroup species were analyzed. The resultant trees (maximum parsimonious, maximum likelihood and Bayesian trees of the combined data of the three gene sequences) indicated that there are two large and three small lineages in the group, some of which were supported by a previous morphology-based phylogeny. In all the analyses, the small lineage composed of two Korean species is sister to the rest of the subgenus, but relationships of other four lineages differed among the analyses and remained unresolved. The implications of the present results are discussed in terms of taxonomy and biogeography of the group. [ABSTRACT FROM AUTHOR]

Thinobius andinus sp. nov. from Argentina is described and illustrated, detailed information on its ecology is provided and a key to species of Thinobius from south-western South America is given. This species was collected from high elevation stream areas of the Mendoza River watershed. It belongs to pollution-sensitive species, and it was mainly found in clear, low-salinity cold waters pertaining to high elevation streams with riparian vegetation. Lectotype is designated for Thinobius pulchripennis Bernhauer, 1923. [ABSTRACT FROM AUTHOR]

To clarify the effects of forest fragmentation in urban landscapes on the abundance, species richness, dominance, and species composition of ground beetles (Coleoptera: Carabidae and Brachinidae), we compared the beetles collected in 12 pitfall traps from April to July and from September to November between three continuous suburban forests and eight isolated urban forests (0.06–1.02 ha), most of which were in the precincts of shrines and temples in Hanshin District, Honshu, Japan. A total of 28 species and 4178 individuals of ground beetles were collected. Segregation of urban forests from continuous suburban forests has changed the species composition and resulted in the loss of some large-sized forest species and the addition of some non-forest species. Simpson's index of dominance (λ) also increased in the urban forests. The richness of forest species markedly decreased with the reduction in forest area but not with the distance from continuous forests, although the species richness of non-forest species did not change with them. Also, species composition changed only with forest area. These findings indicate that continuous forests do not necessary serve as a “mainland” for urban forest species and that every urban habitat, however small in size, acts as a temporary reservoir of species. In comparison with populations of small-sized species, populations of large-sized forest species appeared to decline more readily during forest fragmentation. [ABSTRACT FROM AUTHOR]

Locomotor activity rhythm was examined at various temperatures under a 16 h light : 8 h dark photoperiod (LD 16:8) or LD 12:12 using adults of the burying beetle Nicrophorus quadripunctatus. At 20°C, the locomotor activity of the beetles showed a bimodal daily pattern with two peaks around lights on and lights off under both photoperiods. This bimodal activity rhythm persisted under constant darkness; therefore, the activity of adult N. quadripunctatus is controlled by a circadian clock. Adults showed a bimodal activity pattern for temperatures ranging from 15 to 25°C. The evening peak of the daily activity was earlier at lower temperatures. These findings suggest that in the field, N. quadripunctatus shows crepuscular activity, and is active earlier in the afternoon in cooler seasons. In this species, therefore, temperature appears to play an important role in the determination of daily activity patterns. [ABSTRACT FROM AUTHOR]

Populations of forms intermediate between Carabus (Ohomopterus) insulicola and Carabus (Ohomopterus) arrowianus occur at the boundaries between the two species in the Kiso Valley, Nagano Prefecture, central Honshu, Japan. Morphological and mitochondrial DNA analyses revealed that these populations are derived from a hybrid swarm established as a result of secondary contact between the two species. A similar hybrid swarm has been reported in the Ina Valley, an adjacent river basin separated by the Kiso Mountain Range, where the two species are distributed parapatrically. The hybrid swarm individuals in the two valleys show parallelism in the morphological evolution of the male genitalia upon secondary contact and subsequent formation of hybrid swarms between the two Carabus species. [ABSTRACT FROM AUTHOR]

We report the relative abundance of inflorescence tissue feeders among three willow species (Salix integra,S. miyabeanaandS. sachalinensis) with reference to the plant sexes. We found that (i) a total of 270 individuals belonging to six species and two orders were recorded from willow inflorescences; (ii) the abundance ofXanthiacaterpillars differed across willow species and sexes; (iii) the abundance of weevil larvae differed across willow species; (iv)Gypsonoma bifasciataabundance was affected by sex and inflorescence size; and (v)Nemophora raddeiwas collected from a single femaleS. miyabeanatree. Although nitrogen content of inflorescences is not likely to affect the herbivory pattern of inflorescence tissue feeders, inflorescence size is likely to affect the abundance ofGypsonomacaterpillars. [ABSTRACT FROM AUTHOR]

Although larvae of flea weevils (Curculioninae: Rhamphini) have been known to be leaf miners, larvae of the rhamphine weevil Orchestes hustachei have been found in aphid galls of four Tetraneura species on Ulmus davidiana and in galls of Paracolopha morissoni on Zelkova serrata. This study clarified the feeding habits of O. hustachei larvae and evaluated gall selection by ovipositing females to test the hypothesis of host race formation on their hosts, Tetraneura and Paracolopha galls. When weevil larvae were placed in half-cut galls, they always fed on aphids rather than on gall tissue. When given gall tissue only, all larvae failed to reach adulthood. The number of aphids surviving in a parasitized gall decreased significantly with the development of the weevil larvae. These results suggest that O. hustachei larvae use aphids as their major food source. In the field, ovipositing females did not discern between four Tetraneura species on U. davidiana, in spite of a large difference in suitability as food. Paracolopha morrisoni was introduced into Hokkaido approximately 100 years ago, together with the host plant Z. serrata. It is probable that P. morrisoni has recently come to be used as a host by O. hustachei in Hokkaido . Host choice experiments using Tetraneura sp. O and P. morrisoni galls indicated that female weevils from Z. serrata preferred P. morrisoni to Tetraneura sp. O galls, while females from U. davidiana selected the two types of gall randomly. On Z. serrata, female weevils selected larger P. morrisoni galls, while on U. davidiana, females did not show a preference for gall size. These results suggest that a host shift to P. morrisoni galls may have led to an initial stage of host race formation between the weevil population using Tetraneura galls on U. davidiana, and that using P. morrisoni galls on Z. serrata. [ABSTRACT FROM AUTHOR]

The genus Skidmorella Johnson, previously known only from the South Pacific islands, is discovered in Japan. The type species, Skidmorella magnifica Johnson, is confirmed from Japan as the first record of the species other than the type locality. In addition, two new species, Skidmorella amamiana sp. nov. and Skidmorella quadrisulucia sp. nov., are described from the Ryukyus, Japan. Phylogenetic relationships of the genus Skidmorella and its allies are discussed on the basis of their morphological characters. [ABSTRACT FROM AUTHOR]

Abstract A new species of the pselaphine genus Odontalgus is described from Honshu, Japan, under the name of Odontalgus masaoi . Odontalgus coreanus Löbl known from North Korea is recorded for the first time from Kyushu, Japan. These are the first formal records of the tribe Odontalgini from Japan. [ABSTRACT FROM AUTHOR]

Although intensive care for offspring by both parents is rare in arthropods, it occurs in some species including the beetle Lethrus apterus. According to previous publications, in this species the male collects leaves, which are used by the female to form balls in the underground nest burrow. These balls serve as food for the hatched offspring. Most knowledge about the behavior of this species is based on information collected more than a century ago. Therefore, we investigated above-ground breeding behavior and the status of nest burrows of this beetle in its natural habitat in Hungary. Our results suggest that contrary to previously documented cases, above-ground parental care, i.e. the collection of leaves, is done predominantly not by the males but the females. Further research is needed to understand the role of the sexes in parental care in this species and to explain the discrepancy between the previously documented cases and the results we report here. [ABSTRACT FROM AUTHOR]

Jujiroa estriata Sasakawa (Coleoptera: Carabidae: Platynini) was recently described based on a single male from a mountain in Kyushu, southwest Japan (type locality: Hagi, Gokanoshô). Here we report collection of the species from a new locality, Mount Osuzuyama. We also describe some reproductive traits based on the materials obtained (one male and four females, collected in late May). The male formed sperm bundles in which the head of each spermatozoon was embedded in a rod-shaped structure (spermatodesm). Each spermatodesm was elongate (average length 2.44 mm; cf. male body length 10.8 mm), without a conspicuous spiral structure. Three of the females were dissected, and were found to have 11 or 12 mature eggs in their oviducts. This study provides the first description of sperm bundle morphology for a species of the tribe Platynini and preliminary data on the breeding type of Jujiroa Uéno. [ABSTRACT FROM AUTHOR]