Contribution to the knowledge of seed-beetles (Coleoptera, Chrysomelidae, Bruchinae) in Xinjiang, China

Abstract Nineteen species of seed-beetles belonging to the subfamily Bruchinae (Coleoptera, Chrysomelidae) were collected in Xinjiang, China. Of these, the following four were new records for China: Bruchus affinis Frolich, 1799, Bruchus atomarius L., 1761, Bruchus loti Paykull, 1800 and Kytorhinus kergoati Delobel & Legalov, 2009. We provide an annotated checklist, illustrations and a key to the 19 species.


Introduction
Xinjiang Uygur Autonomous Region (hereafter referred to as Xinjiang, also known as Sinkiang) is a provincial region in the northwest of the People's Republic of China. It is the largest Chinese administrative division and it spans over 1.6 million km 2 . The region is bordered by eight countries: Russia, Mongolia, Kazakhstan, Kyrgyzstan, Tajikistan, Afghanistan, Pakistan and India.
Four tribes of the Chrysomelidae subfamily Bruchinae have been recorded in Xinjiang: Amblycerini, Bruchini, Kytorhinini and Rhaebini (Anton 2010, Tan andYu 1980) and six tribes according to Bouchard et al. (2011): Amblycerini, Bruchini, Eubaptini, Kytorhinini, Pachymerini and Rhaebini. Kytorhinini and Rhaebini are monotypic and restricted to Central Asia and the temperate Holarctic region, respectively (Borowiec 1987, Delobel andLegalov 2009). The majority of Bruchinae species, commonly called bean weevils or seed-beetles, feed on grain legumes and seeds of leguminous trees and shrubs. Many species have a significant economic impact because they can consume valuable protein-rich crops that would otherwise be eaten by humans (Southgate 1979). Despite this, little is currently known about the seed-beetles of Xinjiang. Fifteen species have been documented (Hoffmann 1965, Tan and Yu 1980, Zhang et al. 1987, Xu 1991, Anton 2010, Sui et al. 2011, but most of the records lack detailed information about their distribution.

Methods
We checked all seed-beetles specimens from Xinjiang (most collected from 1956 to 1978) in National Zoological Museum of China (NZMC), Institute of Zoology, Chinese Academy of Science (IZCAS), in Beijing, China. In order to increase the material currently available in the NZMC collection, we collected twice in Xinjiang in July 2009 and August 2013. Seed-beetles were obtained in the field by sweeping with a sweep net and by collecting seeds of host plants in day time. We also tried to collect at night, but no seed-beetles were found. The identification of some of the specimens were confirmed by Chinese Chrysomelidae specialist Tan Juanjie and Yu Peiyu of IZ-CAS twenty years ago. All the specimens were identified by comparing the external morphological features and the male genitalia morphological characters with some published articles again (Lukjanovitsch and Ter-Minassian 1957, Tan and Yu 1980, Borowiec 1987, Kingsolver 2004, Delobel and Legalov 2009. Photographs of all the seed-beetles were taken with a Cannon 5D digital camera and images were processed in Adobe Photoshop CS5. Drawings were created using Adobe Illustrator CS4. All specimens were deposited in the NZMC, where most of them were assigned unique numbers corresponding to the Institute of Zoology collection code entry IOZ(E).

Results
In this study, 19 species of Bruchinae beetles were collected in Xinjiang. They were annotated with updated detailed distribution in the following checklist. The following key is illustrated with photographs of morphological characters used in it. Remarks. We did not find any specimens of A. pallidipennis in Xinjiang in our study, however Tan and Yu (1980) recorded it in Xinjiang. According to Tan and Yu (1980), the North American bruchid A. pallidipennis was introduced to China with its natural host Amorpha fruticosa L. a number of years ago. It has been a major pest of A. fruticosa seeds in China. Distribution. Almost worldwide.

Remarks.
In this study, we found only one specimen of C. chinensis in Xinjiang. Zhang et al. (1987) and Xu (1991), however, recorded Vigna radiata and V. angularis extensively infested by C. chinensis in Kumul and Shihezi, Xinjiang.
Remarks. Although we did not collect any C. maculatus specimens from Xinjiang in this study, Sui et al. (2001)  Remarks. We did not collect any B. dentipes specimens in Xinjiang in this study, but Tan and Yu (1980) previously recorded B. dentipes as occurring in Xinjiang. Remarks. In this study, we did not find any B. pisorum specimens in Xinjiang, but Yixin (1991) previously recorded B. pisorum as occurring in Xinjiang. 46,57,62 Distribution. Worldwide except Australia.

Bruchus rufimanus Boheman, 1833
Remarks. We did not find any B. rufimanus specimens in Xinjiang; however it was previously recorded as occurring there (Tan and Yu 1980 Host. Unknown. Remarks. Delobel and Legalov (2009) described this species based on a single male. We examined a female specimen and found that its antennae are serrated and are slightly longer than half of the body length (Fig. 35, 41, 42). Additionally, the elytra of the female are almost yellow, with the exception of a black, elongate triangular area, which extends from the base to one-third of the elytral suture (Fig. 35)

Discussion
Chinese literature on Bruchinae is out-of-date because of the recent changes in generic and tribal classification and description of new species (Borowiec 1987, Bouchard et al. 2011, Delobel and Legalov 2009 The Bruchinae of Xinjiang remain relatively poorly investigated and it is likely that many additional species can still be found in the region. Further fieldwork is required to ascertain if the paucity of data is due to a genuinely small number of species, or the result of insufficient collection efforts.