Dasycerine rove beetles: Cretaceous diversification, phylogeny and historical biogeography (Coleoptera: Staphylinidae: Dasycerinae).

Within the hyperdiverse beetle family Staphylinidae, Dasycerinae is one of the smallest and most cryptic subfamilies, comprising a sole extant genus characterized by a latridiid beetle-like body form. Little has been known about their early diversification, character evolution, phylogeny and historical biogeography because of limited fossil material and lack of a phylogeny integrating extant and extinct representatives. Here we report an unexpectedly diverse dasycerine fauna from the mid-Cretaceous of northern Myanmar, including a new genus and four new species. To reconstruct the early evolutionary history of Dasycerinae, we present a phylogenetic framework of the subfamily based on a dataset integrating all extant and extinct taxa using parsimony, maximum-likelihood and Bayesian methods. †Cedasyrus gen. n., characterized by distinct sexual dimorphism in antennal and elytral lengths, is recovered as the basal-most lineage, sister to the remaining two extinct genera and all living Dasycerus species. †Vetudasycerus is recovered as sister to †Protodasycerus + Dasycerus. Among all extinct taxa, †Protodasycerus bears distinctly longer elytra, and appears to represent a transitional form from †Vetudasycerus to Dasycerus. Phylogenetic inferences and ancestral distribution reconstruction support an "Out-of-Orient" model for Dasycerinae. Either the Bering- or North Atlantic Land Bridge may have served as a passageway for dasycerine dispersal between Eurasian and North American continents. An elevation-reconstruction analysis indicated that the ancestor of the extant Dasycerus probably lived at a high altitude and stayed at this elevation through the end of the Miocene. We propose that the extinction of dasycerine ancestors living on the Tethyan islands at low altitude was likely caused by sea-level rise and climatic warming during the Late Cretaceous. The high-altitude areas might have played the role of refugia that harboured subalpine derivatives which eventually gave rise to the extant Dasycerus.

Range extension and sexual dimorphism in Megabatrus caviceps Löbl (Coleoptera, Staphylinidae, Pselaphinae).

Megabatrus caviceps Löbl, originally described from Kuatun, Fou-kien (= Guadun, Fujian), eastern China, is recorded from the Nanling Nature Reserve, Guangdong, southern China, ca. 550 km SW from the type locality. The female of this species is discovered and described for the first time. For comparative purposes, male diagnostic characters of M. caviceps are figured and supplementary description is provided. Some new data on this species' biology are given.

Zopherobatrus gen. n. (Coleoptera: Staphylinidae: Pselaphinae), a new troglobitic batrisine from southwestern China.

A new genus and new species of the pselaphine tribe Batrisini, Zopherobatrus tianmingyii Yin & Li gen. et sp. n., is described based on material collected from a cave in Guizhou, southwestern China. The new taxon exhibits a typical suite of morphological adaptations to life in caves, and represents a third genus of the cave-inhabiting Pselaphinae in China.

New species and new record of Megatyrus Hlavác & Nomura (Coleoptera: Staphylinidae: Pselaphinae) from Asia.

A new species, Megatyrus femoralis sp. n., is described from the Koshi Zone, East Nepal, with major diagnostic features illustrated. Megatyrus masumotoi Nomura, Sakchoowong & Chanpaisaeng, originally described from southwestern Thailand, is recorded from the Noring Timur Mountain, West Malaysia. The above data extends the known range of Megatyrus about 1,200 km to the west, and 870 km to the south.

A new species of Syndicus (s. str.) Motschulsky (Coleoptera, Staphylinidae, Scydmaeninae) from East China.

Syndicus (s. str.) jaloszynskii Yin and Song, new species is described from Fujian and Zhejiang, East China. All material was collected in rotten woods. The habitus of both sexes, aedeagus, and spermatheca are illustrated. The new species can be readily separated from all known congeners by the strikingly large body size, the structure of aedeagal endophallus, and the form of spermatheca. This is the first species of the nominotypical subgenus of Syndicus known to occur in China.

A new species of Lasinus Sharp (Coleoptera: Staphylinidae: Pselaphinae) from East China.

Lasinus orientalis Yin & Bekchiev, new species, is described from the eastern Chinese provinces of Zhejiang and Jiangxi, with major diagnostic features illustrated. The new species is compared with, and distinguished from related congeners.

Two new species of ant-loving beetles (Coleoptera: Staphylinidae: Pselaphinae) from Jiulong National Wetland Park, China.

Continued collecting efforts at the Jiulong National Wetland Park, Zhejiang, East China revealed two additional species of the ant-loving beetle subfamily Pselaphinae (Coleoptera: Staphylinidae): Trisiniotus jiulong sp. nov. and Arthromelodes lianghongbini sp. nov. Both new species are diagnosed, described, and their important characters are illustrated.

Notes on synonymy of Diartiger Sharp with Microdiartiger Sawada (Coleoptera: Staphylinidae: Pselaphinae), with description of two new species from East China.

The relationship of the clavigerite genera Diartiger Sharp and Microdiartiger Sawada is discussed, and the synonymy of the two genera proposed by Besuchet (1986) is followed. This results in two new combinations: D. thinhi (Nomura), comb. n. and D. songxiaobini (Yin & Li), comb. n. Two new species, D. dentatus Yin & Li, sp. n. and D. yaoluopingensis Yin & Li, sp. n. are described from Anhui, East China, and new locality data for D. songxiaobini from Anhui and Jiangxi is provided. The new species and D. songxiaobini from Anhui were simultaneously collected from colonies of Lasius sp. nesting under stones. The Diartiger species are newly placed in two groups: the D. japonicus-group and the D.fossulatus-group. A key is provided to assist in identification of the Diartiger species from China.

Smetanabatrus kinabalu (Staphylinidae: Pselaphinae: Batrisitae), a new genus and new species from Sabah, Borneo.

A new genus and new species of the pselaphine tribe Batrisini, Smetanabatrus kinabalu gen. et sp. n., is described from Sabah, East Malaysia. Both sexes of the new species have securiform maxillary palpi, with the male exhibiting extreme abdominal modification. Illustrations of the habitus and major diagnostic features, as well as a discussion on the taxonomic placement of the new taxon is provided. A key to genera of the Batrisini from Borneo is provided.

On the identity of Pselaphodes walkeri (Sharp, 1892) (Coleoptera: Staphylinidae: Pselaphinae), with description of a new related species.

The identity of Pselaphodes walkeri (Sharp, 1892) is clarified based on examinations of the holotype and recently collect-ed material from the type locality (Damao Island, Zhoushan Archipelago). Previous records of P. walkeri from West Tian-mushan Mountain (Zhejiang), Baishanzu Natural Reserve (Zhejiang) and Wuyishan Mountain (Jiangxi) are proven to be based on misidentifications, populations there represent a new species closely related to P. walkeri. Both P. walkeri and the new species are redescribed/described, illustrated and distinguished from the other members of the genus.

Redescription of Tyrus Aubé and T. sinensis Raffray (Coleoptera: Staphylinidae: Pselaphinae), and two new species from Sichuan, Southwest China.

The genus Tyrus Aubé is redescribed with major diagnostic features illustrated. The first male specimen of T. sinensis Raffray (Type locality: Yunnan, China) is reported from Xizang, China, and two new species, Tyrus sichuanicus Yin & Nomura, sp. n. and Tyrus yajiangensis Yin & Li, sp. n., are described from Sichuan, China. All treated species are (re-)described, illustrated and distinguished.

Description of two new species of the genus Tmesiphodimerus gen. n. (Coleoptera: Staphylinidae: Pselaphinae) from South Asia.

Tmesiphodimerus Coulon and Yin, new genus (Pselaphitae: Tmesiphorini) is proposed for T. sinensis Yin and Coulon, new species from Hainan, South China (type species), and T. malaysianus Coulon and Yin, new species from Perak, West Malaysia. The new taxa are described, with their major diagnostic features illustrated. The taxonomic placement of Tmesiphodimerus is discussed.

A third species of Pakistatyrus Hlavác (Coleoptera: Staphylinidae: Pselaphinae).

The pselaphine genus Pakistatyrus Hlavác (Pselaphitae: Tyrini) is represented by two species distributed in high mountain areas of the Himalaya. Here a third species, P. schmidti sp. nov., is described from Nepal. The species is characterized by the simple male antennae, large foveae of the pronotum and elytra, greatly reduced elytra, and conspicuously asymmetric aedeagus. A key to and an updated distribution map of the species of Pakistatyrus is provided.

A new species of Physomerinus Jeannel (Coleoptera, Staphylinidae, Pselaphinae) from Jiulong National Wetland Park, China.

Physomerinusjiulongensissp. nov. is described from a series of overwintering individuals collected in decomposing wood at Jiulong National Wetland Park, East China. The new species is characterized and separated from related congeners by the unique form of the sexually dimorphic maxillary palpi, greatly swollen male metafemora, as well as by the shape of the genitalia of both sexes. A key to, and a distributional map of, Physomerinus species occurring in China and on the Ryukyu Islands, Japan is provided.

Range extension and male description of a rare clavigerite beetle in China (Coleoptera: Staphylinidae: Pselaphinae).

The myrmecophilous clavigerite Anaclasiger zhudaiae Yin & Huang is known from a single female collected in Guangdong, southern China. Here, I report the discovery of this species in Hunan, central China, associated with Nylanderia flaviabdominis (Wang) ants, which extends its range approximately 630 km northward from the type locality. The male is described for the first time, and the habitus and other major diagnostic characters are illustrated. Ex-situ photographs of living beetles and a map showing the distribution of Anaclasiger Raffray are provided.

Redescription and a new record of Centrophthalmus sinensis Raffray, 1904(Coleoptera: Staphylinidae: Pselaphinae).

A new record of Centrophthalmus sinensis Raffray, 1904 from Suzhou, East China is provided, which is also the first Pselaphinae known to occur in this city, and the third pselaphine species from Jiangsu Province. A redescription of the species is given, aided with illustrations of the habitus and other morphological details.

A new species of Tyrodes Raffray (Coleoptera: Staphylinidae: Pselaphinae) from China.

A new species of the small pselaphine genus Tyrodes Raffray (Pselaphitae: Tyrini), T. tibialis sp. nov., is described and illustrated from Guangxi, southwestern China. This species can be separated from its congeners mainly by the aedeagal characters as well as by the modified sternite 2 (V), and presence of a preapical projection of the metatibiae.

The genus Pseudophanias Raffray (Coleoptera, Staphylinidae, Pselaphinae) from Nanling Priority Area for Biodiversity Conservation, China.

Prior to this study, no species of Pseudophanias Raffray had been reported from Nanling, a vast biodiversity conservation area that spans five provinces in southern China. In this paper, three new species of the genus are described: Pseudophaniasfurcilobussp. nov. (Guizhou, Guangxi), P.leigongsp. nov. (Guizhou), and P.mulunsp. nov. (Guangxi), suggesting that additional study on the diversity of this group in the area is required. These species are characterized, keyed, and compared to similar congeners, supplemented with illustrations of the habitus and other morphological characters.

New material of Euroleptochromus tuberculatus Yin & Cai (Coleoptera: Staphylinidae: Scydmaeninae) in Eocene Baltic amber.

The extinct members of the ant-like stone beetle supertribe Mastigitae are among the best studied groups of all fossil Scydmaeninae, and their evolutionary history can be traced from the latest Albian to the earliest Cenomanian through Miocene/Oligocene, with seven extinct genera being described (summarized in Jaoszyski, 2016; Jaoszyski & Perkovsky, 2016; Jaoszyski et al., 2018; Ross, 20192022 (list of Burmese amber taxa)).

Two new riparian Pselaphinae from Hubei, Central China (Coleoptera: taphylinidae).

The Pselaphinae fauna of Hubei Province in central China is extremely poorly documented. Here we describe two new species recently collected at a riverbank near Chongyangs county seat. Batrisiella riparia sp. nov. is characterized by the greatly swollen metafemora of the male, and Nipponobythus varicornis sp. nov. has a darkish-colored body, and uniquely modified male antennal clubs and metaventrite. Illustrations of the habitus and taxonomically informative characters of both species are provided for a reliable identification.