Research Article |
Corresponding author: Hongbin Liang ( lianghb@ioz.ac.cn ) Academic editor: Boris M. Kataev
© 2021 Pingzhou Zhu, Hongliang Shi, Hongbin Liang.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Zhu P, Shi H, Liang H (2021) The first record of the genus Laemostenus from China, with descriptions of two new species from the Himalaya (Carabidae, Sphodrini, Sphodrina). ZooKeys 1017: 77-88. https://doi.org/10.3897/zookeys.1017.61383
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The genus Laemostenus is recorded from China for the first time, and two new species are described: L. (Pristonychus) zhentangensis sp. nov. (type locality: Dinggyê County, Xizang), and L. (P.) zhamensis sp. nov. (type locality: Nyalam County, Xizang). The relationships of these new species are briefly discussed.
brunneus species group, ground beetle, new record, Pristonychus, taxonomy, Xizang
The genus Laemostenus Bonelli, 1810, containing 14 subgenera and more than 200 described species, is widely distributed in the Western Palaearctic Region (Europe, North Africa, West and Central Asia, and Himalaya) (
Pristonychus Dejean, 1828 was established as a genus for Carabus terricola Herbst, 1784 but was subsequently reduced to a subgenus of Laemostenus (
During our recent expeditions to Xizang, two specimens of Sphodrina were collected from Zhêntang and Zham towns in the valleys of the south Himalaya near the border with Nepal. They can be readily recognized as species of the genus Laemostenus due to the pubescence on the dorsal sides of tarsomeres 2–5. They both belong to the brunneus species group of the subgenus Pristonychus according to Casale’s work (1988) and represent two different new species. These are the first records of the genus Laemostenus from China.
The primary purpose of this paper is to record the genus Laemostenus from China and describe two new species. In addition, the relationships of these new species are briefly discussed. For the new species, complete descriptions, illustrations, and a distribution map are provided.
Specimens examined during our study are deposited in the Institute of Zoology, Chinese Academy of Sciences, Beijing, China (
Abbreviations for measurements used in the paper are as follows: body length (BL) was measured from the apical margin of the labrum to the elytral apex; body width (BW) was measured across the elytral greatest width (EW). Pronotum width (PW) was measured across its greatest width; basal width of pronotum (PBW) was measured along its basal margin; pronotum length (PL) was measured along its median line. Elytra length (EL) was measured along the suture from the base of the scutellum to the elytra apex.
China, Xizang: Dinggyê (27.9161°N, 87.4607°E), altitude 3151 m.
Holotype
: male (
Body dark brown. Head slightly narrow. Eyes small, slightly prominent laterally; tempora oblique, as long as eyes. Elytra with lateral margins straight near sutural angles; sutural angles acute. Parascutellar pores present. Ventral side of profemora smooth, with one seta on posterior margin, without tooth on anterior margin. Mesotibiae faintly curved in male. Meso- and metatibiae with a dense brush of reddish-yellow setae in apical half. Metatrochanters reniform, not elongate. Apical lamella of median lobe short, length half its basal width, apex slightly truncate. Right paramere strongly curved (the angle between basal and apical portions near 90°), distinctly widened at middle, strongly narrowed to apex, apex very thin.
This new species belongs to the brunneus species group sensu
Among this species group, the new species is most similar to Laemostenus (Pristonychus) arthuri (Morvan, 1982) and L. (P.) migliaccioi (Casale, 1982), both from Nepal, sharing the ventral side of profemora with one or two setae on posterior margin and the subcordate pronotum. The new species differs from them by the narrower head, the slightly larger eyes, and the slightly truncate apical lamella of the aedeagus. The apical lamella of the aedeagus is rounded in L. (P.) arthuri and emarginate in L. (P.) migliaccioi, and both species have a more globular head with smaller eyes.
(male). BL = 15.6 mm, BW = 5.9 mm. Body (Fig.
Head
(Fig.
Pronotum
(Fig.
Elytra
elongate, EL/EW = 1.61, slightly dilated towards apex, widest at posterior third; lateral margins straight before sutural angles, sutural angles acute (Fig.
Venter. Propleuron, mesepisternum, and metepisternum smooth. Mesosternum not denticulate in front of mesocoxae. Metepisternum long and narrow. All abdominal sternites with a few shallow wrinkles laterally, without ambulatory setae.
Legs long and slender; ventral side of profemora smooth, with one seta on posterior margin, without tooth on anterior margin; protibiae with sparse pubescence on apices; mesotibiae faintly curved (in male); meso- and metatibiae inner sides with a dense brush of reddish-yellow setae in apical half; metatrochanters reniform; tarsi elongate and narrow; metatarsomere 1 sparsely pubescent dorsally; claws smooth on internal margin. Protarsomeres 1–3 distinctly dilated and with ventral adhesive vestiture in male.
Male genitalia. Median lobe (Fig.
Female unknown.
This species is only known from Zhêntang Town, Dinggyê County, Xizang, China (Fig.
The new species is named for its type locality, Zhêntang Town.
There is an unusual character in this new species: only four setae are present on the anterior margin of labrum instead of six, but they are irregularly arranged (Fig.
China, Xizang: Nyalam (27.9815°N, 85.9770°E), altitude 2163 m.
Holotype
: male (
Body dark brown. Head medium in width. Eyes very small, hardly prominent laterally; temporae slightly swollen, twice as long as eyes. Elytra with lateral margins distinctly sinuate near sutural angles; sutural angles rounded. Parascutellar pores absent. Ventral side of profemora smooth, with one seta on posterior margin, without tooth on anterior margin. Mesotibiae faintly curved in males. Meso- and metatibiae inner sides with a dense brush of reddish yellow setae in apical half. Metatrochanters reniform, not elongate. Apical lamella of median lobe short, length half its basal width, apex slightly truncate, somewhat rounded. Right paramere strongly curved (the angle between basal and apical portions near 120°), slightly widened at middle and slightly narrowed apically, apex moderately thin.
This new species also belongs to the brunneus species group, as does the previous new species.
It is distinguishable from most species of this group by the absence of the parascutellar pores on the elytra. There are three other species in this species group which have this character: Laemostenus (Pristonychus) tentiobtusus (Morvan, 1979), L. (P.) brunneus (Hope, 1831), and L. (P.) pseudobrunneus Casale, 1981, from India and Nepal. Laemostenus (P.) zhamensis sp. nov. differs from the first by the ventral side of profemora not having a tooth on the anterior margin, and it differs from the latter two species by the narrower and not globular head and the shallow and impunctate striae of the elytra.
(male). BL = 15.9 mm, BW = 5.5 mm. Body (Fig.
Head
(Fig.
Pronotum
(Fig.
Elytra
elongate, EL/EW = 1.65, slightly dilated towards apex, widest at posterior third; lateral margins distinctly sinuate near sutural angles; sutural angles rounded (Fig.
Venter. Propleuron, mesepisternum, and metepisternum smooth. Mesosternum not denticulate in front of mesocoxae. Metepisternum slightly longer than wide. All abdominal sternites with a few shallow wrinkles laterally, without ambulatory setae.
Legs long and slender; ventral side of profemora smooth, with one seta on posterior margin, without tooth on anterior margin; protibiae with sparse pubescence on apices; mesotibiae faintly curved (in male); meso- and metatibiae with a dense brush of reddish yellow setae in apical half of their inner sides; metatrochanters reniform, not elongate; tarsi elongate and narrow; metatarsomere 1 sparsely pubescent dorsally; claws smooth on internal margin. Protarsomeres 1–3 (in male) distinctly dilated and with ventral adhesive vestiture.
Male genitalia. Median lobe (Fig.
Female unknown.
This species is only known from Zham Town, Nyalam County, Xizang, China (Fig.
The new species is named for its type locality, Zham Town.
There are many lineages of the genus Laemostenus in the Himalaya, representing different species groups of the subgenera Pristonychus and Laemostenus. The two new species from southern Xizang belong to the brunneus species group, subgenus Pristonychus, according to
We wish to thank Prof. Zong Shixiang (Beijing Forestry University, BJFU), Ms Ren Lili (BJFU), Mr Zhao Bin (Forestry and Grassland Administration of the Tibet Autonomous Region), and Mr Jin Pengfei (Forestry and Grassland Administration of Xigazê Prefecture) for their support and assistance during our expeditions in Xizang. We are grateful to Mr Yan Weifeng (BJFU), Mr Ge Sixun (BJFU) and Mr. Zhu Xiaoyu (Ningbo, Zhejiang) for their help in collecting specimens for the study. Thanks also to Dr Ilya Kabak (Saint Petersburg), Dr Joachim Schmidt (Rostock), Dr. Borislav Guéorguiev (Sofia), and Dr Achille Casale (Milan) for their comments during the review process. This work was supported by grants from the the Biodiversity Survey and Assessment Project of the Ministry of Ecology and Environment, China (grant no. 2019HJ2096001006), National Natural Science Foundation of China (grant no. 31970400), and the Key Collaborative Research Program of the Alliance of International Science Organizations (grant no. ANSO-CR-KP-2020-04).