Integrative taxonomy and species distribution models of the genus Diamesus Hope, 1840 (Coleoptera: Staphylinidae: Silphinae).

Integrative taxonomy of Diamesus Hope, 1840 (Coleoptera: Silphinae) is presented. Adults of D. bimaculatus Portevin, 1914 (endemic to Taiwan) and D. osculans (Vigors, 1825) (widely distributed from northern India to Australia) are redescribed, keyed and figured, including characters of the male and female genitalia of both species. Variation in elytral maculation in D. osculans is discussed and illustrated. The absence of diagnostic differences of D. osculans var. reductus Pic, 1917 from D. osculans is discussed, and the former name is confirmed as a junior subjective synonym of D. osculans. Types of all three names available were studied; a lectotype and paralectotypes are designated for the name D. osculans var. bimaculatus Portevin, 1914. Molecular phylogenetic analysis confirms the genus Diamesus is sister group to the genus Necrodes Leach, 1815, and D. osculans and D. bimaculatus are two, well supported clades. Detailed data on the distribution of D. bimaculatus and D. osculans are presented and mapped. Species distribution models for both species were created and interpreted. Diamesus osculans is reported for the first time from India: Uttarakhand, China: Anhui, Hainan, Hunan, Jiangxi, Shaanxi and Zhejiang Provinces, and Australia: Victoria; it is also recently confirmed from Taiwan, being sympatric in distribution there with D. bimaculatus. Available data on the ecology and seasonality of both species of Diamesus are also discussed.

emOiceoptoma/em emtangi/em (Coleoptera: Silphidae: Silphinae), a new species of carrion beetle from eastern China.

A new species, Oiceoptoma tangi Sommer, Ruzicka, Nishikawa Schneider, new species, from Zhejiang Province, China, is described and illustrated. The new species is closely related to O. subrufum (Lewis, 1888), distributed in Central and North-eastern China, the Korean Peninsula, Far East of Russia and Japan, and to O. nigropunctatum (Lewis, 1888), endemic to Japan. All three species are keyed, and distribution maps of all three species are presented.

Revision of the genus Ptomaphagus Hellwig from eastern Asia (Coleoptera, Leiodidae, Cholevinae).

The species belonging to the genus Ptomaphagus Hellwig, 1795 (Coleoptera, Leiodidae, Cholevinae, Ptomaphagini) from eastern Asia are assigned to three species groups. Group yasutoshii has a single species: P. (s. str.) yasutoshii Nishikawa, 1993 from Taiwan, China. Group nepalensis with three species: P. (s. str.) nepalensis Perreau, 1988 from Nepal and P. (s. str.) masumotoi Nishikawa, 2011 from Thailand are redescribed, and P. (s. str.) piccoloi Wang, Ruzicka, Nishikawa, Perreau & Hayashi, 2016 is recorded for the first time from China (Zhejiang). Group sibiricus with seven species, including two newly described Chinese ones P. (s. str.) funiu sp. n. from Henan, and P. (s. str.) haba sp. n. from Yunnan, and five known species: P. (s. str.) chenggongi Wang, Nishikawa, Perreau, Ruzicka & Hayashi, 2016, P. (s. str.) hayashii Wang, Ruzicka, Perreau, Nishikawa & Park, 2016, P. (s. str.) kuntzeni Sokolowski, 1957 (distribution records from Myanmar excluded), P. (s. str.) sibiricus Jeannel, 1934 and P. (s. str.) tingtingtae Wang, Nishikawa, Perreau, Ruzicka & Hayashi, 2016. Specimens of other undescribed species of the group sibiricus are also recorded, revealing a high diversity of this genus in eastern Asia, especially in central and north Sichuan, China, which essentially remains to be investigated. Relevant morphological characters of the examined species are illustrated with colour plates, and their known distributions are mapped. A key to species of Ptomaphagus from eastern Asia is provided.

Silent evolution.

Phylogenetic analyses using mitochondrial DNA sequences of several kinds of beetles have shown that their evolution included a silent stage in which no morphological changes took place. We thus propose a new category of evolutionary process called "silent evolution".

Revision of the genus Ptomaphagus Hellwig (Coleoptera, Leiodidae, Cholevinae) from Japan.

After examining Japanese material of Ptomaphagus Hellwig from various collections, a new species is described, Ptomaphagus (s. str.) piccoloi sp. n., and a new subjective synonym proposed, Ptomaphagus (s. str.) kuntzeni Sokolowski, 1957 = Ptomaphagus (s. str.) amamianus Nakane, 1963, syn. n., in this paper. Relevant morphological characters of examined species of Ptomaphagus are illustrated with colour plates, and known distributions are mapped.

Revision of the genus Ptomaphagus Hellwig (Coleoptera, Leiodidae, Cholevinae) from Taiwan Island.

Ptomaphagus (s. str.) chenggongi sp. n. and Ptomaphagus (s. str.) tingtingae sp. n. (Coleoptera, Leiodidae, Cholevinae, Ptomaphagini) are described from Taiwan Island. In addition, a new subjective synonym is proposed, Ptomaphagus (s. str.) yasutoshii Nishikawa, 1993 = Ptomaphagus (s. str.) smetanai Perreau, 1996, syn. n. Relevant morphological characters of the examined Ptomaphagus species are illustrated with colour plates, and their known distributions are mapped.

Revision of the genus Ptomaphagus Hellwig (Coleoptera, Leiodidae, Cholevinae) from the Russian Far East and the Korean Peninsula.

The conundrum of Ptomaphagus (s. str.) sibiricus Jeannel, 1934 (Coleoptera, Leiodidae, Cholevinae, Ptomaphagini) is solved, and it is redescribed and newly recorded in South Korea. A new species is also described from the Russian Far East: Ptomaphagus (s. str.) hayashii sp. n. Relevant morphological characters of the concerned species are illustrated with colour plates, and their known distributions are mapped.

Revision of Palearctic and Oriental Necrophila Kirby et Spence, part 3: subgenus Calosilpha Portevin (Coleoptera: Silphidae: Silphinae).

A taxonomic revision of the subgenus Calosilpha Portevin, 1920 (of the genus Necrophila Kirby & Spence, 1828) through Asia is presented. Four valid species are recognized: (1) Necrophila (C.) brunnicollis (Kraatz, 1877), widely distributed from Bhutan and China: Yunnan province to Far East of Russia and Japan (including Ryukyu Islands); (2) N. (C.) cyaneocephala (Portevin, 1914), endemic to Taiwan; (3) N. (C.) cyaniventris (Motschulsky, 1870), widely distributed from northern India to Vietnam and southern China (east to Hainan Island); and (4) N. (C.) ioptera (Kollar & Redtenbacher, 1844), comb. nov. (ex Calosilpha), widely distributed in Pakistan, India (Himachal Pradesh to Assam) and Nepal. Eusilpha (Calosilpha) bicolor imasakai Nishikawa, 1986 and Eusilpha (Calosilpha) kurosawai Nishikawa, 1986 are confirmed as junior subjective synonyms (sensu Cho & Lee 1995, Ji 2012) of Silpha brunnicollis Kraatz, 1877. Description of important adult taxonomic characters (including male genitalia) and a key to species is included. Georeferenced records for all four species are mapped. First reliable records of Necrophila (Calosilpha) brunnicollis from China: Hong Kong and Anhui, Fujian, Gansu, Hubei, Jiangxi, Jilin, Qinghai and Zheijiang provinces and Guangxi autonomous region; N. (C.) cyaniventris from India: Himachal Pradesh, Uttarakhand, Meghalaya, Arunachal Pradesh, Nagaland and Manipur; and N. (C.) ioptera from Pakistan, India: Uttarakhand, Uttar Pradesh, Bihar, Sikkim, West Bengal and Assam are given (only imprecise records from "Himalaya" had been published for the last two species). First records of N. (C.) brunnicollis from Bhutan, and of N. (C.) cyaniventris from China: Hainan and Yunnan provinces, Myanmar, Laos and Cambodia are given. Parsimony analysis supports the monophyly of Calosilpha, with two clades, one formed by N. (C.) brunnicollis and N. (C.) cyaneocephala and the other by N. (C.) cyaniventris and N. (C.) ioptera. Geometric morphometrics discriminated four taxa of Necrophila (Calosilpha). Results indicated a sexual dimorphism between sexes in all species. Shape variability was concluded between the taxa. Populations of N. (C.) brunnicollis from continental Asia and three regions of Japan (Honshu + Shikoku, Kyushu and Ryukyus) also were examined. MANOVA was significant and supported shape differences in male and female populations. When testing each pair of groups by discriminant analysis, only differences between male populations from Japan (Kyushu) and those from Japan (Honshu + Shikoku) showed insignificance.

Loss of flight promotes beetle diversification.

The evolution of flight is a key innovation that may enable the extreme diversification of insects. Nonetheless, many species-rich, winged insect groups contain flightless lineages. The loss of flight may promote allopatric differentiation due to limited dispersal power and may result in a high speciation rate in the flightless lineage. Here we show that loss of flight accelerates allopatric speciation using carrion beetles (Coleoptera: Silphidae). We demonstrate that flightless species retain higher genetic differentiation among populations and comprise a higher number of genetically distinct lineages than flight-capable species, and that the speciation rate with the flightless state is twice that with the flight-capable state. Moreover, a meta-analysis of 51 beetle species from 15 families reveals higher genetic differentiation among populations in flightless compared with flight-capable species. In beetles, which represent almost one-fourth of all described species, repeated evolution of flightlessness may have contributed to their steady diversification since the Mesozoic era.

Effects of vacancy defects on the interfacial shear strength of carbon nanotube reinforced polymer composite.

We investigate the effects of the vacancy defects (i.e., missing atoms) in carbon nanotubes (CNTs) on the interfacial shear strength (ISS) of the CNT-polyethylene composite with the molecular dynamics simulation. In the simulation, the crystalline polyethylene matrix is set up in a hexagonal array with the polymer chains parallel to the CNT axis. Vacancy defects in the CNT are introduced by removing the corresponding atoms from the pristine CNT (i.e., CNT without any defect). Three patterns of vacancy defects with three different sizes are considered. Two types of interfaces, with and without cross-links between the CNT and the matrix are also considered here. Polyethylene chains are used as cross-links between the CNT and the matrix. The Brenner potential is used for the carbon-carbon interaction in the CNT, while the polymer is modeled by a united-atom potential. The nonbonded van der Waals interaction between the CNT and the polymer matrix and within the polymer matrix itself is modeled with the Lennard-Jones potential. To determine the ISS, we conduct the CNT pull-out from the polymer matrix and the ISS has been estimated with the change of total potential energy of the CNT-polymer system. The simulation results reveal that the vacancy defects significantly influence the ISS. Moreover, the simulation clarifies that CNT breakage occurs during the pull-out process for large size vacancy defect which ultimately reduces the reinforcement.