A key to species of subgenus Lithochlaenius (Coleoptera, Carabidae, Chlaeniini, Chlaenius), with descriptions of three new species

Abstract Three new species of genus Chlaenius Bonelli subgenus Lithochlaenius Kryzhanovskij are described from China: Chlaenius chuanqianensis Liu & Liang, sp. n. (type locality: Xishui, Guizhou Province), Chlaenius linwensini Liu & Liang, sp. n. (type locality: Fujian Province), and Chlaenius propeagilis Liu & Kavanaugh, sp. n. (type locality: Gaoligongshan, Yunnan Province). Seven species of the subgenus are redescribed: Chlaenius agiloides Jedlička, Chlaenius formosensis Lorenz, Chlaenius agilis Chaudoir, Chlaenius leishanensis Kirschenhofer, Chlaenius noguchii Bates, Chlaenius rambouseki Lutshnik, and Chlaenius wrasei Kirschenhofer. Additional taxonomic changes include the following: Chlaenius formosanus Jedlička is treated as a junior synonym of Chlaenius rambouseki Lutshnik and Chlaenius anchomenoides Bates, syn. n. and Chlaenius nuristanus Jedlička as junior synonyms of Chlaenius agilis Chaudoir, syn. n. Chlaenius latroLaFerté-Sénectère is considered a nomen nudum stat. n. and unavailable, leaving Chlaenius agilisChaudoir as the next available name. Chlaenius nuristanusaberration rubridipesJedlička is also an unavailable name. Chlaenius formosensisLorenz (=Chlaenius formosanusHabu) is returned to species status stat. n. A key to adults of the 10 known species of subgenus Lithochlaenius is provided.

measured along the longitudinal diameter of the eye (dorsal-lateral view); PL = length of pronotum measured along median line; PW = pronotum width at its widest point; EL = elytron length from base to apex; EW = width across both elytra at widest point (equal to body width).
Wherever we refer to abdominal ventral plates, we use the numbering system that recognizes the generally accepted segmental homologies in Carabidae. Thus the first visible sternum (i.e. the sternum divided medially by the hind coxae) in Chlaenius adults is sternum II and the last visible sternum is sternum VII.
All photographs were taken through a Nikon stereoscopic dissecting microscope fitted with a Canon 450D camera, and were edited by Helicon Focus and Photoshop software.
Specimens examined in the course of this study were deposited at the following collections: Guangxi, Guizhou, Sichuan, Yunnan, Tibet), North Korea, Japan, Russia (Far East), Afghanistan, Pakistan, India. The known localities of Lithochlaenius species are shown in Fig. 158. Based on the work of Andrewes (1930) and Paik et al. (2006), members of this subgenus also occur in Indo-China (Laos, Cambodia, Vietnam), but we have not studied specimens from those countries.  Biology. Members of this subgenus are typically collected on sandy beaches of rivers or streams . Adults of some species (e. g., C. agiloides, C. rambouseki) have been observed feeding on mollusks, worms, and dragonfly larvae at night . A few species have also been collected in light traps.
Remarks. Based on the metallic body surface, single supraorbital seta, antennomere 3 longest and antennomeres 4-11 densely pubescent, Lithochlaenius species can be recognized as a member of the genus Chlaenius. Members of this subgenus are similar to those of subgenus Stenochlaenius in shape of the pronotum, but the latter are much smaller and have a glabrous body surface.
As presently conceived, the subgenus can be divided into two species groups: 1) the rambouseki group, members of which have all elytral intervals densely and more or less equally pubescent, and males have aedeagi slender in dorsal view; and 2) the agilis group, members of which have at least elytral intervals 1-5 glabrous medially with pubescence restricted to the strial depressions, intervals 6-9 densely pubescent, and males have aedeagi generally stouter in dorsal view. Most species of the subgenus have restricted geographical ranges, and only C. rambouseki is more broadly distributed.
In his treatment of the North American species of genus Chlaenius, Bell (1960) suggested that his solitarius species group, which included C. cordicollis Kirby, C. leucoscelis Chevrolat, C. prasinus Dejean, C. purpureus Chaudoir, and C. solitarius Say, represented a distinct group within his subgenus Chlaenius sensu stricto. He noted that the range of this group extends south into South America and that "Related forms occur in the Old World". In the paper in which he proposed Lithochlaenius as a replacement name for Hemichlaenius Lutshnik, Kryzhanovskij (1976:16) cited Bell's paper and suggested that C. solitarius might be a North American representative of that subgenus. Robert Davidson (personal communication) shares the view that species of Bell's solitarius group, and at least five additional species in Middle and South America, are likely related to some if not all Lithochlaenius species. All of these New World species share most of the diagnostic features of Lithochlaenius and all of them have elytral pubescence as seen in members of the rambouseki group. However, members of all these New World species are distinguished in having the lateral and basal elytral margins smoothly continuous around the humeri without forming any trace of an angle and the elytral epipleura and basal regions smoothly continuous around the humeri, not separated by a carina of any kind. These were the main features that Bell used to distinguish members of his solitarius group. In contrast, members of all the Asian species of Lithochlaenius that we have studied have a distinct humeral angle formed at the junction of the lateral and basal elytral margins and a more or less distinctly carinate separation of the (lateral) epipleural from the basal (anterior vertical) elytral surfaces. Hence, Asian Lithochlaenius specimens could not be identified as members of the solitarius groups using Bell's (1960) key. There is also greater variation in the development of the elytral basal margin (from complete to partially interrupted) and in the length and shape of the apical lamella of the male aedeagus among New World species than we have seen among the Asian Lithochlaenius species. Consequently, we suggest that placement of any New World species in subgenus Lithochlaenius would be premature at this time and should await a more comprehensive, worldwide treatment of genus Chlaenius and analyses of phylogenetic relationships among the included species, species groups, and subgenera.
Head and pronotum black with green or coppery metallic luster; elytra black; ventral surface black; mandibles and trochanters dark brown; antennomere 1, femora, tibiae yellow to brown; antennomeres 2-11, palpi and tarsi dark brown to nearly black.
Etymology. The Latinized name chuanqianensis refers to type localities of this new species in "chuanqian" regions, of which "chuan" refers to Sichuan Province and "qian" refers to Guizhou Province).
Geographical distribution. Fig. 158. Known only from Guizhou and Sichuan Provinces, China.
Remarks. Mensural data cited in the description were obtained from the holotype and all paratypes.
Members of this species are most similar to those of C. wrasei in shape of antennomere 1 and elytral pubescence, but differ from the latter in color of antennomere 1 (paler than antennomere 3 in C. chuanqianensis, antennomeres 1 and 3 concolorous in C. wrasei) and orientation of the apical lamella of the aedeagus of males (straight in C. chuanqianensis, bent ventrally in C. wrasei).
They are also similar to C. leishanensis members in pubescence of elytral intervals, but different from the latter in having yellow tibiae (black or dark brown in C. leishanensis), and males have a thin aedeagal lamella of the aedeagus (lamella thick in C. leishanensis males).
Etymology. The Latinized name linwensini refers to Mr. Lin Wensin, an excellent insect collector who died during a recent collecting trip to Hainan, China.
Geographical distribution. Fig. 158. Known only from Fujian Province, China. Remarks. Mensural data cited in the description were obtained from the holotype and all paratypes.
Male members of this species are similar to those of C. formosensis in the shape of the lamella of aedeagus, but males and females differ from those of the latter in having antennomere 1 coniform (cylindrical in C. formosensis), elytral intervals 6-7 pubescent throughout (glabrous medially in C. formosensis), and males have the aedeagus convex ventrally in the middle portion (straight in C. formosensis males).
Etymology. The Latinized name propeagilis refers to the similarity of members of this species to those of C. agilis.
Geographical distribution. Fig. 158. Known only from southeastern Tibet and Yunnan Province, China.
Remarks. Mensural data cited in the description were based on measurements obtained from 5 males and 5 females selected for maximum variation.
Specimens of Chlaenius (Lithochlaenius) collected from western Yunnan were initially determined as Chlaenius agilis Chaudoir. However, after comparison of the male genitalia with those of type specimens of C. agilis, we are convinced that they represent a distinct new species. Males differ from those of C. agilis in having the median lobe of aedeagus gradually bent near the base in lateral view (Fig. 122), whereas C. agilis males have the median lobe abruptly bent with a depression near the base (Fig. 124).
This species is clearly very closely related to C. agilis. At present, the known ranges of these two species are broadly disjunct (Fig. 158). We know of no locality records for any Chlaenius (Lithochlaenius) species from the intervening area (i.e., between northcentral India and southeastern Tibet and western Yunnan Province. Whether this distributional gap represents a real disjunction or is only an artifact of inadequate collecting in the area to date can only be determined from additional sampling efforts in the region. It would be particularly informative to determine whether or not any populations representing the propeagilis/agilis lineage occur in the region and, if so, whether or not males display intermediate genitalic traits.
Geographical distribution. Fig. 158. Known only from eastern Afghanistan, Pakistan, and northern India.
Remarks. Mensural data cited in the description were obtained from type and cotype specimens examined. The name Chlaenius agilis Chaudoir was once treated as a junior synonym of Chlaenius latro LaFerté-Sénectère (Csiki 1931. However, in his work, LaFerté-Sénectère (1851) did not provide a specific description of Chlaenius latro. This means that Chlaenius latro LaFerté-Sénectère is a nomen nudum, and therefore, unavailable.  considered Chlaenius nuristanus Jedlička to be a junior synonym of Chlaenius anchomenoides Bates. We have examined the types and/or cotypes of C. agilis Chaudoir, C. anchomenoides, C. nuristanus and its aberration C. nuristanus a. rubridipes, and found no significant differences between them, except for variation in the color of antennae and legs. The aedeagi are abruptly bent near the base in all dissected males (Figs 124, 139, 141, 143). Mandl (1972:104) assigned Chlaenius anchomenoides to genus Stenochlaenius. Based on the pubescent elytral intervals and incomplete elytral basal margin in members of C. anchomenoides, we do not agree with this assignment.
Geographical distribution. Fig. 158. Known only from Taiwan. Remarks. Mensural data cited in the description were based on measurements obtained from 5 males and 5 females selected for maximum variation.
This species was first described as a subspecies of C. noguchii. Later, Morita (1993) upgraded it to a distinct species. However, the name C. formosanus was preoccupied by another Chlaenius species of Jedlička, and therefore Lorenz (1998) renamed it C. formosensis. Kirschenhofer (2005:491) considered Chlaenius formosensis Lorenz to be a junior synonym of C. formosanus Jedlička (= Chlaenius rambouseki Lutshnik, see below) with no comparison. Based on Habu"s original description (type unavailable according to Morita), named specimens of C. formosensis in Morita's collection (corresponding author and checked by HBL in 2009), and specimens in Chen Chanchin's collection, we treat C. formosensis as a distinct species. Its members differ from those of C. rambouseki in having the vertex of the head and pronotal disk glabrous (both sparsely punctate and pubescent in C. rambouseki), intervals 1-7 glabrous medially (wholly pubescent in C. rambouseki), and the male aedeagus stout (slender in C. rambouseki).
Head and pronotum black with strong green or bluish green metallic luster; elytra black with very weak blue luster; ventral surface black; legs, antennae, mandibles and palpomere dark brown.
Geographical distribution. Fig. 158. Confirmed only from Japan. Remarks. Mensural data cited in the description were based on measurements obtained from 5 males and 5 females selected for maximum variation.
This species may well be endemic to Japan, and its reported occurrence in Korea (Kwon and Lee 1986) and Vietnam (Paik et al. 2006) requires further clarification. The slender aedeagus of males of this species is very different from the stout aedeagi of other species of the agilis group.
Remarks. Mensural data cited in the description were based on measurements obtained from 5 males and 5 females selected for maximum variation.
Chlaenius wrasei was first described as a subspecies of C. noguchii by Kirschenhofer. Later , he upgraded this taxon to status as a distinct species. We agree with this decision, given that the pubescent elytral intervals 6-7 of adults and stout aedeagus of males are very different from those of C. noguchii.
Members of C. wrasei are similar to those of C. leishanensis in having antennomere 1 coniform and pronotum nearly impunctate, but differ from the latter in having intervals 1-5 wholly glabrous medially (only the basal portions of these intervals are glabrous medially in C. leishanensis), tibiae concolorous with femora (tibiae much darker than femora in C. leishanensis), and lamella of aedeagus thin and less bent ventrally (thickened and more markedly bent in C. leishanensis).
Remarks. Mensural data cited in the description were based on measurements obtained from 5 males and 5 females selected for maximum variation.
We compared a photograph of the holotype (type lost according Kryzhanovskij 1976) and specimens of C. formosanus from Taiwan with identified specimens of C. rambouseki Lutshnik from Ussuri River, and no significant difference was found between them.
provided specimens of C. rambouseki Lutshnik and translations of important papers published in Russian. Dr. Jirí Hájek took photographs of the type specimens of C. agiloides Jedlička and C. formosanus Jedlička. Dr. Robert Davidson generously shared with us his knowledge of the New World chlaeniines and his thoughts on possible relationships between Asian Lithochlaenius species and members of the New World solitarius species group of Chlaenius. The corresponding author (Liang) also thanks Dr. Yves Bousquet and Dr. Thierry Deuve for discussion and good suggestions for treating Chlaenius latro LaFerté-Sénectère. This work was supported by grants from the Knowledge Innovation Program (Grant No. KSCX2-YW-Z-0907) and National Science Foundation of China (Grant No. 30570213) to the Institute of Zoology (Beijing), and by grants from the U. S. National Science Foundation (Grant No. DEB-0103795) and the National Geographic Society  to the California Academy of Sciences.