Definition of the jianfengling species group of the ground beetle genus Orthogonius MacLeay (Coleoptera, Carabidae, Orthogoniini)

Abstract The jianfengling species group of the termitophilous carabid genus Orthogonius MacLeay, 1825 is defined and reviewed. This species group ranges from southern China, crossing Indochina and Myanmar to eastern India. To date, the jianfengling species group is composed of ten species, including six new species which are hereinafter described and illustrated: Orthogonius wrasei sp. n. (Myanmar), Orthogonius bellus sp. n. and Orthogonius limbourgi sp. n. (Vietnam), Orthogonius politior sp. n., Orthogonius aberlenci sp. n. (Laos) and Orthogonius meghalayaensis sp. n. (India). Habitus, elytral apices and male genitalia of all species are illustrated. A key to species and a distribution map of jianfengling species group are provided.


Introduction
Indo-Burma is one of the 25 biodiversity hotspots in the world for conservation priorities (Myers et al. 2000). It covers a large tropical area of more than two million square kilometers, from eastern India, through Myanmar to southern China to the east, and to northern of Malaya Peninsula to the south. The termitophilous ground beetles of the tribe Orthogoniini are very rich in species diversity in this area, represented by approximately 100 species (Tian and Deuve 2000, 2006, 2010, Tian et al. 2012. The majority of orthogoniine species recorded in tropical Asia belongs to the prominent genus Orthogonius MacLeay, 1825. As the series works to understand the faunal composition and to set up a rational classification system of Orthogonius, the lancangjiang and baconii species groups have already been dealt with Deuve 2013, 2016). In the present paper we define the jianfengling species group.
The jianfengling species group is comprised of members of large, polish, depressed and glabrous orthogoniine beetles. The first species of this group, O. jianfengling Deuve, was described in 2000 from Hainan Island, China. Then, O. himalayicus Tian &Deuve, 2005 (from Bhutan andSikkim, India), O. freyi Tian & Deuve, 2006 (from Myanmar) and O. duboisi Tian & Deuve, 2006 (from Yunnan, China) were recorded respectively Deuve 2005, 2006). To date, ten Orthogonius species are designed as members of the jianfengling species group, including six new species described below.

Material and methods
All specimens for this study are dry and mounted materials. Dissection and observation of the specimens were made using a WILD M32 binocular microscope. Detailed descriptions are provided for the new species, while only diagnostic character states are given for the known species. Digital photographs were taken and processed in the same as in Tian and Deuve (2013).
Body length was measured from apex of right mandibles to apex of elytra; body width = width of elytra.
Male: Unknown. Remarks. It is probably close to O. limbourgi sp. n., distinguished from the latter by its distinctly reflexed lateral expanded margins of pronotum (slightly reflexed in O. limbourgi), and setose middle coxae (asetose in O. limbourgi).

Description.
Head and pronotum black, antennae and elytra dark brown, slender and very shinny; body smooth and glabrous, head and pronotum impunctate, elytral odd intervals with a few, sparse punctures which are irregularly arranged; head intricately wrinkled; microsculptural engraved meshes densely isodiametric, faint on head and pronotum, clear on elytra. Head slightly longer than wide, HL/HW = 1.15-1.18; labrum deeply emarginate at front; eyes comparatively small, but prominent; mentum edentate and bisetose, submentum bisetose. Pronotum transverse, PW/PL = 1.91-1.94, rather flat, lateral expanded margin wide and slightly reflexed, widest at middle. Elytra elongate and rather slender, EL/EW = 1.74-1.77, parallel-sided at middle, moderately convex, widest slightly behind middle, apex obliquely truncate, inner angles roundly obtuse (Fig. 15); striae very deep, intervals distinctly convex, the 3 rd intervals generally with three setiferous pores. Legs moderately long, middle coxae setose, the 3 rd and 4 th hind tarsomeres subequal in length, all tarsal claws weakly pectinate. Prosternal process unbordered at apex. Male genitalia  with the median lobe of aedeagus comparatively small and short, middle portion convex, apex pointed in lateral view, turning to right, obtuse dorsally.
Remarks. Differs from other congeners by its deeply concaved labrum and broadly obtuse inner apex of elytron.
Distribution. Bhutan and Sikkim (Fig. 3i). Diagnosis. A medium-sized species, light dark brown in general, with rather flat and slender body which is smooth and glabrous, and asetose midcoxae and well bordered prosternal process.
Head longer than wide, HL/HW = 1.12-1.14, eyes small but prominent, frons and vertex moderately convex, frontal impressions large and deep; clypeus bisetose, basal portion even; labrum sex-setose, shallowly emarginate at front margin; palps slender, subcylindrical, the 3 rd maxillary palpomere as long as the 4 th which is glabrous, the 3 rd palpomere with two short setae at apex; the 2 nd labial palpomere slightly longer than the 3 rd , bisetose in inner margin, with several additional setae at subapex and apex, the 3 rd labial palpomere with a few setae at basal part; ligula small, bisetose at apex; mentum edentate; each of mentum and submentum bisetose (but an additional seta on the left of mentum in male), palpiger asetose. Antennae moderately long, extending over base of elytra; pubescent from basal 1/3 of the 4 th antennomere, slightly expanded at pubescent portion of the 4 th ; the 3 rd antennomere almost as long as the 4 th .
Pronotum strongly transverse, PW/PL = 1.59-1.62, disc moderately convex, apical and basal margins well beaded, sides evenly expanded, widest at middle; base slightly wider than apex, bisinuate on base, slightly concave on apical margin; hind angle rounded off; lateral expanded margin well defined, evenly and indistinctly reflexed; both transversal impressions distinct, basal foveae small and deep.
Elytra elongate, and rather flat; EL/EW = 1.64-1.65; widest at about middle, sides parallel at middle, basal border complete, apex bisinuate, inner angle broad, with a small denticle (Fig. 16); striae moderately deep, intervals convex, odd and even intervals subequal in width in middle, the 3 rd interval with three setiferous pores; the 7 th interval simple.
Legs slender, fore tibiae expanded at apex, with outer angle strongly protrude, outer margin serrate; hind femora rather slender, with three posterior setae; middle coxae setose, hind coxae smooth and glabrous; middle tibiae quite straight, slightly expanded at apex; hind tibiae slightly expanded at apex, apical spurs long and sharp, the 3 rd hind tarsomere slightly longer than the 4 th which bilobed at apex; all tarsal claws weakly pectinate.
Prosternal process well bordered at apex. Abdominal ventrite VII of male complete; ventrite VII with two pairs of setae on either side of apical margin in both male and female.
Male genitalia: Stout, dorsal opening wide and long, base dilated, gently bent ventrally towards apex, which almost pointed in lateral view; in dorsal view, not contracted before apical lamella, which short and broad, as long as wide, surface granulated.
Remarks. It is allied to O. politior sp. n., but its clypeus bisetose (quadrisetose in O. politior), prosternal process well-bordered at apex (unbordered in O. politior), and the apical lamella of aedeagus shorter and broad at apex (longer and narrow in O. politior).

Diagnosis.
A species similar to but larger than the above one, with also a rather flat and slender body, but having an unbordered prosternal process, a quadrisetose clypeus and setose midcoxae.
Description. Length: 19.0 mm; width: 6.8 mm. Habitus as in Fig. 7. Body elongate, strongly shiny, smooth and glabrous. Head and disc of pronotum dark brown; elytra, lateral expanded margins of pronotum, mouthparts, antennae, legs and ventral surface reddish brown. Head and pronotum impunctate, elytral odd intervals with a few punctures; head moderately wrinkled; pronotum and elytra largely smooth. Microsculptural engraved meshes isodiametric on elytra, rather transverse on pronotum, indistinct on head.
Head longer than wide, HL/HW = 1.09, eyes small but prominent, frons and vertex convex, frontal impressions large and deep; clypeus quadrisetose in male, basal portion even; labrum sex-setose, shallowly emarginate at apical margin; palps slender, subcylindrical, the 3 rd maxillary palpomere as long as the 4 th which glabrous, the 3 rd maxillary palpomere with two short setae at apex; the 2 nd labial palpomere slightly longer than the 3 rd , bisetose on inner margin, with several additional setae at subapex and apex, the 3 rd labial palpomere with a few setae at basal part; ligula small, bisetose at apex; mentum edentate; each of mentum and submentum bisetose (but a third seta on the left of mentum in the holotype), palpiger asetose. Antennae moderately long, extending over base of elytra; pubescent from basal 1/3 of the 4 th antennomere, slightly expanded at pubescent portion of the 4 th ; the 3 rd as long as the 4 th .
Pronotum strongly transverse, PW/PL = 1.60, disc quite flat, apical and basal margins well beaded, sides evenly expanded, widest at middle; base wider than apex, bisinuate on base, slightly concave on apical margin; lateral expanded margin well defined, evenly and distinctly reflexed; both transversal impressions distinct, basal foveae small and deep.
Elytra elongate-ovate, EL/EW = 1.75; widest at about middle, sides parallel at middle, basal border complete, apex bisinuate, inner angle broad, but shortly denticulate (Fig. 17); striae moderately deep, intervals convex, subequal in width of odd and even intervals in middle, the 3 rd interval with three setiferous pores; the 7 th interval normal.
Legs rather slender, hind femora rather slender, with three posterior setae; fore tibiae expanded at apex, with outer angle strongly protrude, outer margin serrate; middle coxae setose, hind coxae smooth and glabrous; middle tibiae quite straight, slightly expanded at apex; hind tibiae slightly expanded at apex, apical spurs long and sharp, the 3 rd hind tarsomere slightly longer than the 4 th which bilobed at apex; all tarsal claws weakly pectinate.
Prosternal process unbordered at apex. Male genitalia (Figs 28-30): Median lobe of aedeagus stout, dorsal opening wide and long, base dilated, gently bent ventrally towards apex, which almost pointed in profile; in dorsal view, median lobe distinctly contracted before apical lamella which short and thin, longer than wide.
Female: Unknown. Remarks. It is very similar to O. limbourgi, with the differences mentioned above. Etymology. Referred to its polished body. Distribution. Laos (Fig. 3d). Paratypes. 1 male & 3 females, in MNHN, SCAU and CIRAD (Montpellier). Diagnosis. A medium-sized and stout species, with a shiny, smooth, and glabrous body which is brownish in general, and having an edentate mentum, a well bordered prosternal process and setose midcoxae.
Head as long as wide, eyes moderate and prominent, frons and vertex convex, frontal impressions large and deep, extending posteriorly to the level of anterior supraorbital pores; clypeus bisetose, basal portion decorated by three short, longitudinal furrows which crossing base of clypeus and joining frontal impressions on either sides, and against frons medially; labrum sex-setose, moderately emarginate at apical margin; palps stout, subcylindrical, the 3 rd maxillary palpomere slightly shorter than the 4 th , glabrous on the 4 th , the 3 rd with three short setae at apex; the 2 nd labial palpomere slightly longer than the 3 rd , bisetose on inner margin, with several additional setae at subapex and apex, the 3 rd labial palpomere with a few setae at basal part; ligula small, bisetose at apex; mentum edentate; each of mentum and submentum bisetose, setae subequal in length, palpiger asetose. Antennae moderately long, extending over base of elytra; pubescent from basal 1/3 of the 4 th antennomere, where evidently expanded; the 3 rd antennomere almost as long as the 4 th , the 1 st with a long seta at subapex.
Pronotum strongly transverse, PW/PL = 1.65, disc quite flat, apical and basal margins well beaded, sides evenly expanded, widest at middle; base wider than apex, bisinuate on base, slightly and widely concave on apical margin; lateral expanded margins well defined, narrow, evenly and distinctly reflexed; fore transversal impression faint, hind one distinct, basal foveae small but deep.
Elytra elongate, EL/EW = 1.70-1.75; widest at about middle, almost parallelsided at middle, basal border complete, apex widely and nearly obliquely truncated on outer margin, then reversely truncated nearly the tip, inner angle nearly rectangular, not denticulate (Fig. 18); striae moderately deep, intervals convex, intervals subequal in width in middle, the 3 rd interval with three setiferous pores; the 7 th interval normal.
Legs moderately long, hind femora moderately expanded, with three posterior setae in male and four or five in female; fore tibiae expanded at apex, with outer angle shortly protruded, outer margin sub-serrate; middle coxae glabrous in holotype, but with one to three setae in median portion in other specimens, hind coxae smooth and glabrous; middle tibiae not modified in male, quite straight, serrate, gradually expanded towards apex; hind tibiae slightly expanded at apex, apical spurs very long and sharp, the 1 st hind tarsomere distinctly longer than the 2 nd , the 3 rd as long as the 4 th which deeply and symmetrically bilobed at apex; all tarsal claws weakly pectinate.
Prosternal process bordered at apex. Abdominal ventrite VII of male complete, with two pairs of setae on either side of apical margin in both male and female.
Male genitalia (Fig. 31-32): Short and stout, dorsal opening wide and long, somewhat expanded medially, gently bisinuate ventrally towards apex, which short and blunt in lateral view; apical lamella short and small, not parallel-sided, wider than long, apex broad.

Remarks.
It is probably allied to O. limbourgi sp. n. as they have similar structure of aedeagus. But it is easily separated from O. limbourgi and O. politior sp. n. by its short and more convex body, and short apical lamella of the aedeagus.
Etymology. The name of this new species is in honor of the collector, Henri-Pierre Aberlenc (CIRAD, Montpellier), an excellent entomologist and a friend of the second author.

Diagnosis.
A fairly large species, with a yellowish and slender body which is less depressed, but strongly shiny, smooth and glabrous, having a bordered prosternal process, an edentate mentum and asetose midcoxae.
Description. Length: 18.5 mm; width: 7.0 mm. Habitus as in Fig. 9. Body elongate, strongly shiny, smooth and glabrous. Yellowish to brown, except head which dark brown. Head and pronotum impunctate, elytral odd intervals with a few punctures. Microsculptural engraved meshes isodiametric on head and elytra, transverse on pronotum.
Head longer than wide, HL/HW = 1.12, eyes small but prominent, frons and vertex convex, frontal impressions deep and long, extending beyond the level of fore supraorbital setae; clypeus bisetose, basal portion of surface uneven; labrum sex-setose, faintly emarginate at apical margin; palps slender, subcylindrical, the 3 rd maxillary palpomere as long as the 4 th which glabrous; the 3 rd maxillary palpomere with two short setae at apex; the 2 nd labial palpomere slightly longer than the 3 rd , bisetose on inner margin, with several additional setae at subapex and apex; the 3 rd labial palpomere with a few setae at basal part; ligula small, bisetose at apex; mentum edentate; each of mentum and submentum bisetose, palpiger asetose. Antennae rather long, extending basal one third of elytra; pubescent from basal one third of the 4 th antennomere, slightly expanded at pubescent portions; the 3 rd antennomere almost as long as the 4 th .
Pronotum strongly transverse, PW/PL = 1.64, disc moderately convex, apical and basal margins well beaded, sides evenly expanded, widest at middle; lateral expanded margin well defined and reflexed, surface uneven; both transversal impressions well marked, basal foveae small and deep.
Elytra elongate-ovate, EL/EW = 1.69; widest at about apical one third of elytra, sides parallel at middle, basal border complete, apex broadly sinuate, inner angle nearly rectangular (Fig. 19); striae deep, intervals distinctly convex, subequal in width with each other at middle, the 3 rd interval with three setiferous pores. Legs rather slender, fore tibiae slightly expanded at apex, outer angle distinctly protruding and sharp, outer margin somewhat sub-serrate; middle and hind coxae smooth and glabrous; middle tibiae quite straight, slightly expanded at apex; hind tibiae hardly expanded at apex, apical spurs long and sharp; the 3 rd hind tarsomere as long as the 4 th which deeply bilobed at apex; claws weakly pectinate.
Female: Unknown. Remarks. Probably close to O. limbourgi sp. n., but its body less depressed, and hind 3 rd tarsomere as long as 4 th (versus in O. limbourgi).
Etymology. "Bellus", a Latin word meaning beautiful, refering to the charmof this species.
Remarks. Differs from other members of this species group by its labrum straight at front, and 3 rd elytral interval with only two setiferous pores.

Diagnosis.
A dark brown or black species, having a elongate body, a deeply emarginate labrum, an edentate mentum, a well bordered prosternal process, setose midcoxae and a 6-setose ventrite VII.
Description. Length: 18.5-19.0 mm; width: 6.5 mm. Habitus as in Fig. 12. Body elongate, shiny. Head and disc of pronotum black to dark brown; elytra, lateral expanded margins of pronotum, mouthparts, antennae, legs and ventral surface reddish dark brown. Female darker than male. Head and pronotum impunctate, elytral odd intervals with a few punctures; head densely and moderately wrinkled and intricate; pronotum transversally striate, elytra smooth. Microsculptural engraved meshes isodiametric on elytra, rather transverse on head and pronotum.
Head longer than wide, HL/HW = 1.04, eyes small but prominent, frons and vertex convex, frontal impressions deep; clypeus bisetose, basal portion of surface uneven; labrum sex-setose, deeply emarginate at apical margin; palps slender, subcylindrical, the 3 rd maxillary palpomere as long as the 4 th which glabrous, the 3 rd maxillary palpomere with two short setae at apex; the 2 nd labial palpomere slightly longer than the 3 rd , bisetose on inner margin, with several additional setae at subapex and apex, the 3 rd labial palpomere with a few setae at basal part; ligula small, bisetose at apex; mentum with a median tooth, but not well-defined; each of mentum and submentum bisetose, palpiger asetose. Antennae moderately long, extending over base of elytra; pubescent from basal one third of the 4 th antennomere, slightly expanded at pubescent portion; the 3 rd antennomere almost as long as the 4 th .
Pronotum strongly transverse, PW/PL = 1.60, disc moderately convex, apical and basal margins well beaded, sides evenly expanded, widest at middle; lateral expanded margins well defined, flat and not reflexed, surface uneven; both transversal impressions distinct, basal foveae small and deep.
Elytra elongate ovate, EL/EW = 1.67, widest at about middle, sides parallel at middle, basal border complete, apex broadly sinuate, inner angle broadly acute (Fig. 22); striae shallow, intervals rather flat or slightly convex, subequal in width with each other in middle, the 3 rd interval with three setiferous pores; the 7 th interval normal.
Legs rather slender, fore tibiae slightly expanded at apex, outer angle distinctly protrude, outer margin somewhat sub-serrate; middle and hind coxae smooth and glabrous; middle tibiae quite straight, slightly expanded at apex; hind tibiae hardly expanded at apex, apical spurs long and sharp, the 3 rd hind tarsomere much longer than the 4 th which deeply emarginate at apex (lobes half as long as the joint); claws weakly pectinate.
Prosternal process unbordered at apex. Ventrite VII with three pairs of setae on either side of apical margin in both sexes.

Diagnosis.
A black (including lateral expanded pronotal margins) and stout species, having nearly rectangular inner apical angles of elytra, an edentate mentum, a well bordered prosernal process and setose midcoxae.
Head longer than wide, HL/HW = 1.11-1.13, eyes rather small but prominent, frons and vertex convex, frontal impressions deep, extending beyond level of the fore supraorbital setae; clypeus bisetose, surface almost even; labrum sex-setose, slightly emarginate at apical margin; palps slender, subcylindrical, the 3 rd maxillary palpomere as long as the 4 th which glabrous, the 3 rd with two short setae at apex; the 2 nd labial palpomere slightly longer than the 3 rd , bisetose on inner margin, with several additional setae, the 3 rd labial palpomere with a few setae at basal part; ligula small, bisetose at apex; mentum without distinct tooth; each of mentum and submentum bisetose, palpiger asetose. Antennae moderately long, extending over base of elytra; pubescent from basal two fifth of the 4 th antennomere, slightly expanded at pubescent portion; the 3 rd almost as long as the 4 th .
Pronotum strongly transverse, PW/PL = 1.76-1.77, disc moderately convex, apical and basal margins well beaded, sides strongly expanded, widest at middle; lateral expanded margins well defined, flat and not reflexed, surface somewhat striate; fore and hind angles broadly rounded; both transversal impressions well marked, basal foveae small and deep.
Legs rather slender, fore tibiae slightly expanded at apex, apical margin sinuate, outer angle distinctly protrude, outer margin sub-serrate; middle coxae setose, hind ones smooth and glabrous; middle tibiae quite straight, slightly expanded at apex; hind tibiae slightly expanded at apex, apical spurs long and sharp, the 3 rd hind tarsomere longer than the 4 th which deeply emarginate at apex (lobes one third as long as the segment); claws strongly pectinate.
Prosternal process well bordered at apex. Ventrite VII quadrisetose in both male and female; Male genitalia (Figs 42-43): Stout and robust, shallowly sinuate ventrally, dorsal opening very wide, gently and gradually narrowed towards apex, which blunt in lateral view; apical lamella very short, and very sharp in ventral view.
Remarks. Recognized by its black body and nearly rectangular inner apical angles of elytra.
Etymology. This new species is named in honor of David W. Wrase (Berlin). Distribution. Myanmar.