Revision of genus Pericalus from China, with descriptions of four new species (Carabidae, Lebiini, Pericalina)

Abstract Nine taxa of the genus Pericalus Macleay from China are revised, with four new species described: Pericalus gibbosus sp. n. (type locality: Putao, Myanmar; one paratype from Mêdog, Xizang), Pericalus elegans sp. n. (type locality: Mêdog, Xizang), Pericalus acutidens sp. n. (type locality: Longchuan, Yunnan), and Pericalus obscuratus sp. n. (type locality: Fanjingshan, Guizhou). Four taxa are newly recorded from China: Pericalus ornatus ornatus Schmidt-Göbel (Yunnan, Hainan), P. obtusipennis Fedorenko (Yunnan), P. amplus Andrewes (Yunnan), and P. dux Andrewes (Yunnan). Pericalus formosanus Dupuis is newly ranked as a subspecies of P. ornatus Schmidt-Göbel. An improved key to world species of the subgenus Pericalus is provided, along with distribution maps and images of habitus and male and female genitalia for all Chinese species.


Introduction
The genus Pericalus belongs to the subtribe Pericalina (Carabidae: Lebiini), distributed in the tropical regions of Oriental-Australasian Realm: the easternmost reaches New Ireland (P. novaeirlandiae), and the westernmost reaches south India (P. fascinator). Pericalus is close to the following four Oriental genera: Lioptera Chaudoir, Coptodera Dejean, Trichocoptodera through the Asian continent tropical-subtropical areas, and the most diverse region is located in northern Myanmar, northeast India, southeast Xizang, and west Yunnan. The remaining eight taxa are distributed in the Sundaland region (Greater Sunda Islands and Malay Peninsula). There are no species endemic to the Philippines or islands in the Wallacea region, but one species is widely distributed in each region, P. cicindeloides in the Philippines, and P. baehri in Sulawesi.
Habitat. Many adults of the subgenus Pericalus were collected in daytime under barks of fallen logs in tropical or subtropical forests. Some others were collected during night, fast running on surfaces of dead logs, or occasionally attracted by lights. Species in this subgenus usually have a rather flat habitus, adapting for living under tree bark.
The supposed ground plan for the subgenus is supposed to include two groups of yellowish patches on the elytron (unicolorous in four species); body very flat (but convex in P. gibbosus); elytra with microsculpture consisting of distinct, very transverse meshes (but nearly isodiametric in P. dux and P. elegans); outer apical angles of elytra distinct, acuminate to rounded; elytral sutural angles sharp or blunt; third interval of the elytra with three setigerous pores (but four pores in four species, usually two in P. o. formosanus).
The shape of outer apical angles of elytra can be classified into the following four basal forms: acuminate, apex forming a very sharp angle, strongly projecting, less than 90 degrees (Fig. 21), present in seven species; acute, apex forming a sharp and distinct angle, not or weakly projecting, more than 90 degrees (Figs 22,24), in two species; obtuse, apex forming an indistinct angle, more than 90 degrees (Figs 23,25), in five species; rounded, apex fully rounded, not angulate , in seven species. There are some taxa, such as P. o. formosanus, with one form of outer apical angle in general (obtuse), but very rarely other forms can be present in a few individuals (rounded or acute).
Most taxa (15 of 19) of the subgenus have two, the anterior and posterior, groups of yellowish patches on elytra; variation includes four and two pattern forms respectively. For different species or individuals belonging to same pattern form, pale markings on certain intervals may be obsolete or their positions moved.
There are four basic forms for anterior patches: round, in six taxa. Usually a single large round or nearly round spot (Figs 1-3, 7-11) occupies some of the third to eighth intervals, two to five intervals in width. In some individuals of P. ornatus (Fig. 12), the spot is somewhat transverse and irregular, similar to the zigzag form, but generally less transverse and with less displacement of odd and even pale markings. Zigzag, in five species. A transverse serrated band occupies the third to seventh intervals (Figs 6,(13)(14)(15), with pale markings on odd intervals anteriorly placed and those of even intervals posteriorly placed. Sometimes pale markings on the third and/or seventh intervals are obsolete. In P. baehri pale markings on the third interval are placed much more anteriorly to those on the remainder of the odd intervals. Separated, in two species. The basic pattern includs five small separated spots, only one interval in width for each, placed on the third to seventh intervals respectively. Sometimes spots on the sixth and seventh intervals are obsolete. Longitudinal positions for all spots are similar to those of the zigzag pattern. Double, a special pattern only for P. cordicollis. The double pattern form is composed of two adjacent large spots: the inner one is in the third and fourth intervals, posteriorly placed; the outer one is in the fifth to eighth intervals, anteriorly placed.
Two basic forms exist for posterior patches: separated, in eleven taxa. The basic pattern is composed of three separate spots : the first one is in the second and third intervals, posteriorly placed; the pale marking on the second interval is occasionally obsolete. The second one is in the fourth to sixth intervals, anteriorly placed; the pale marking on the fourth interval is occasionally obsolete; the pale marking on the sixth interval is adjacent to that on the fifth (P. cordicollis, and some P. ornatus and P. acutidens,Figs 7,11,12), placed much anteriorly to that on the fifth and forming a small separate spot (P. amplus,P. obtusipennis,P. obscuratus,Figs 6,(13)(14)(15), or obsolete (the remaining four species and most P. ornatus and P. acutidens, Figs 8-10). The third one is in the seventh and eighth intervals, posteriorly placed, sometimes a little before the first spot; the pale marking on the eighth interval is usually obsolete, but present in P. cordicollis, and some individuals of some other species. Single, in three species. The basic pattern is a single large round spot in some of the second to seventh intervals, two to four intervals in width (Figs 1-3). In a few individuals of P. longicollis, the pale marking on the third interval is present and placed posteriorly to the main spot, but is obsolete in most individuals.  (Fig. 19). Paratypes (2 ex.): 1 female (IZAS): same data as holotype. 1 female (IZAS), "Xizang, Mêdog; alt 800-1200 m, Chinese Academy of Science"; "1983.11.5-10, Han Yinheng lgt."; "IOZ (E) 1891857".

Key to the world species of the subgenus Pericalus
Diagnosis. Smallest species in the subgenus, body length 7.2-8.5 mm; elytra black with four round yellowish spots, posterior patch in the third and fourth intervals, sometimes expanded onto part of the second and fifth. Pronotum cordiform, lateral margins strongly sinuate before posterior angles; disc with strong wrinkles. Elytra distinctly convex; outer apical angles rounded; sutural angles blunt; third interval with three setigerous pores; striae with large but shallow punctures. Median lobe of aedeagus with apical lamella very long, approximately one-fourth length of median lobe; endophallus with six thumb tack-like spines (Fig. 33).
Comparison. This species can be readily distinguished from other species in this subgenus. The elytral pattern is similar to that of P. dux and P. longicollis, all with four round yellowish spots, but differs from both species by the elytral posterior patch in intervals 3-4, sometimes also part of 2 and 5 (versus in intervals 4-6 or 4-7); elytra much more convex; pronotum strongly sinuate before posterior angles (versus weakly or moderately sinuate); and much smaller body size.
This species is sympatric with P. elegans sp. n., P. acutidens sp. n., and P. amplus. It can be easily distinguished from these species by the different elytra pattern, smaller size, and very convex body.
Description. Body length 7.2-8.5 mm (male holotype 7.2 mm, female paratypes 8.2-8.5 mm). Coloration. Dorsal surface shiny blackish, with very faint violet hue on elytra; legs, antennae, mouthparts reddish brown; elytral anterior and posterior patches as single round spots, yellow or reddish yellow; the anterior one in intervals 4-7 or 4-6, the posterior one in intervals 2-5 or 3-4 (the male holotype with elytral spots smaller than those of the two females, Figs 1-2); ventral side black. Microsculpture faint and isodiametric on vertex and pronotal disc, distinct and linear on elytral intervals. Head with very strong and regular long wrinkles all through clypeus, frons and vertex, reaching or nearly reaching level of posterior margin of eyes, 6-8 wrinkles on each side; eyes strongly prominent; temporae abruptly constricted after eyes. Pronotum cordiform, PW/PL = 1.33-1.38, subequal to the width of head with eyes (PW/HW = 1.00-1.05); posterior margin a little narrower than anterior margin; lateral margins rounded in the middle, strongly sinuate and then straight before posterior angles; posterior angles sharp, nearly rectangular, projecting laterally, with a seta a little before posterior angles; lateral expansions wide; disc strongly convex and wrinkled, with a pair of faint pits on each side; sub-anterior impression distinct, median line strongly incised, not reaching posterior margin; basal fovea very deep, forming trifurcate incisions, extending medially forming W-shaped sub-posterior impression. Elytra ovate, strongly convex; EW/ EL = 0.74-0.75; much wider than pronotum, EW/PW = 1.69-1.83; apical truncation weakly curved; outer apical angles rounded, sutural angles blunt, not pointed; striae deeply incised, with large but very shallow punctures; third interval with three setigerous pores, the first one at approximately basal tenth, the second near middle, the third one close to apex; the first one adjacent to the third stria, the other two close to the second stria; all intervals distinctly convex, seventh and eighth intervals tumid apically, eighth and ninth intervals with sparse fine setae aside of umbilical series; lateral expansions slightly widened at approximately basal third. Male genitalia ( Fig. 33) with median lobe of aedeagus slender and bent, right margin slightly sinuate near middle; apical orifice very large, opened to the left; apical lamella very long, approximately one fourth length of median lobe, flat, in ventral view length approximately 2.8 times basal width, apex rounded; endophallus with six thumb tack-like spines, arranged in two groups, three near the base of apical orifice, the other three near base of median lobe. Right paramere short, apex truncate, not extended. Female genitalia. Internal reproductive system ( Fig. 52): bursa copulatrix with a very long lobe (inferred to accommodate the large apical lamella of aedeagus); spermatheca digitiform, with weak whorl near middle, without basal pedicel, inserted on the joint of common oviduct and bursa copulatrix; spermathecal gland long, inserted near base of spermatheca, apex strongly dilated, base forming long pedicel. Gonocoxite 2 of ovipositor ( Fig. 41) scimitar-shaped, abruptly bent to the outer side at apical fifth; length approximately six times basal width; outer margin with three dorsolateral ensiform setae, the basal one finer and distant from the rest two; inner margin with one doromedial ensiform seta near apex.
Distribution. Only known from Putao (North Myanmar) and Mêdog (Southeast Xizang, China). (Fig. 60) Etymology. The name gibbosus is Latin, meaning humped, referring to the strongly convex elytra of the new species, which are rather flat in all the other species of this subgenus.
Habitat. In north Myanmar (Putao), P. gibbosus sp. n. was collected under bark of a large fallen log next to a path in subtropical rainforest, elevation of 1075m. This species seems to be very rare, due to only two specimens were collected, cohabitates with P. acutidens and P. amplus. Pericalus acutidens was collected in exactly the same microhabitat together with the new species, but it has a wider elevational range and is much more common. Pericalus amplus is also rare in this area.
Remarks. The form of the male genitalia makes P. gibbosus the most unique member in the subgenus, and in the genus as well. Unlike all other examined species, P. gibbosus has the apical lamella very long, approximately one-fourth length of median lobe (less than one tenth in the other species); and the endophallus with thumb tack-like spines (only finely scaled in other species). This species may represent an isolated lineage in the genus; however, from the external characters, P. gibbosus perfectly agrees with the subgenus Pericalus. Moreover, we suspect that Pericalus (s. str.) could be paraphyletic, because all diagnostic characters for the subgenus seem to be plesiomorphic. Nevertheless, phylogeny is not the task of the present paper, and this new species is placed in Pericalus (s. str.). Largest size of all species in the subgenus, body length 15.0-15.9 mm; dorsal surface black, elytra with four round yellowish spots; the anterior one in intervals 4-8, the posterior one in intervals 4-7. Pronotum transverse, PW/PL 1.47-1.50; lateral margins gently sinuate and then straight before nearly rectangular posterior angles; disc with fine wrinkles. Elytra flat; apex very faintly curved; outer apical angles rounded; sutural angles blunt or forming very short tooth; third interval with three setigerous pores, the middle one at approximately anterior third; striae shallow and impunctate; eighth and ninth interval with dense fine setae.

Pericalus (s. str.) dux Andrewes, 1920
Comparison. This species can be easily distinguished from all other known species in the subgenus by its larger size and distinctive elytral pattern (Fig. 3). Two other species P. longicollis and P. gibbosus also have four round spots on elytra, but P. dux has wider spots placed laterally. This species is sympatric with P. ornatus in south Yunnan. These two species can be distinguished by the differences in body sizes, the elytra patterns, and the outer apical angle of the elytra.
Supplemental description. Male genitalia not studied. Female genitalia. Internal reproductive system (Fig. 54): spermatheca short and pedunculate, inserted on the bursa copulatrix; spermatheca tubular, approximately two times length of pedicel; pedicel short, branched near the joint; spermathecal gland absent. Gonocoxite 2 of ovipositor ( Fig. 43) scimitar-shaped, gradually bent to the outer side after apical third; length approximately five times basal width; outer margin with two dorsolateral ensiform setae, the apical one placed near the middle, the basal one on the basal quarter, finer than the apical one; inner margin with one doromedial ensiform seta near apex.
Distribution Diagnosis. Middle size in the subgenus, body length 10.6-11.6 mm; head and pronotum black, elytra unicolorous, cupreous green with a strong metallic hue. Pronotum strongly transverse, PW/PL = 1.65-1.80; lateral margins weakly sinuate before posterior angles; disc without transverse wrinkle. Elytra flat; outer apical angles rounded; sutural angles sharp, forming short tooth; third interval with three setigerous pores; striae shallow and impunctate. Median lobe of aedeagus evenly curved; apical orifice opened to the left side.
Comparison. Only three other species in the subgenus have no yellowish pattern on the elytra. This new species can be readily distinguished from P. cicindeloides and P. fascinator by the presence of three setigerous pores on the third elytral interval (vs. four pores in the other two). From P. aeneipennis, which also has three setigerous pores according to the original description (further discussions, see below), this new species is distinguishable by all wrinkles long on vertex, reaching or nearly reaching level of posterior margin of eyes (vs. wrinkles short, only reaching a little beyond mid-eye level); pronotum much wider, PW/PL more than 1.65 (vs. approximately 1.30); pronotal lateral margins weakly sinuate before posterior angles (vs. strongly sinuate); posterior angles not projecting laterally (vs. projecting a little laterally); elytral outer apical angles completely rounded (vs. "hooked but not toothed"); and quite different distribution ranges.
Description. Body length 10.6-11.6 mm (no significant sexual differences). Coloration. Head and pronotum shiny blackish, with very faint metallic hue; elytra cupreous green, with strong metallic hue; mouthparts, antennomeres 2-11 reddish brown; legs dark brown, trochanters and tarsi yellowish brown; ventral side black. Microsculpture faint and isodiametric on vertex and pronotal disc, distinct and isodiametric or slightly transversal on elytral intervals. Head with strong and irregular wrinkles; four to six short wrinkles on each side extending from clypeus to frons, middle area around frontoclypeal sulcus smooth; five to seven subparalleled long wrinkles along each side of inner margin of eye, reaching level of posterior margin of eyes; inner wrinkles forming concentric rings around the smooth vertex. Eyes very prominent; temporae gradually constricted after eyes. Pronotum strongly transverse, PW/PL = 1.65-1.80, subequal to width of head with eyes (PW/HW = 1.00-1.07); posterior margin a little narrower than anterior margin; lateral margins rounded in the middle, slightly sinuate before posterior angles; posterior angles a little more than rectangular angle, not projecting laterally, with a seta very close to the posterior angles; lateral expansions wide; disc weakly convex, with very faint wrinkles, with a pair of reniform shallow pits on each side; sub-anterior impression shallow, median line fine, not reaching anterior nor posterior margin; basal fovea shallow, extending medially merged with sub-posterior impression, extending posteriorly forming short oblique grooves. Elytra ovate, weakly convex; EW/EL = 0.73-0.78; wider than pronotum, EW/PW = 1.45-1.64; apical truncation weakly curved; outer apical angles rounded, sutural angles sharp, forming short tooth; striae shallowly incised, without punctures; third interval with three setigerous pores, the first one at approximately basal tenth, the second near middle, the third one close to apex; the first one adjacent to the third stria, the other two close to the second stria; intervals weakly convex, the eighth interval tumid apically, the eighth and ninth intervals with very sparse and fine setae aside of umbilical series; lateral expansions widely extended, strongly widened near basal third. Male genitalia (Fig. 34) with median lobe of aedeagus slender and bent, right margin almost straight, ventral margin evenly curved; apical orifice opened to the left; apical lamella short, a little flat, in ventral view length nearly same as basal width, in lateral view weakly constricted before apex; endophallus strongly folded, with fine scales all through length, without spines. Right paramere with apex extended and expanded, securiform. Female genitalia. Internal reproductive system (Fig. 53): spermatheca pedunculate, inserted on the base of common oviduct; spermatheca fusiform, longer than the pedicel; spermathecal gland inserted on the joint of spermathecal pedicel, approximately twice as long as spermatheca (including the pedicel). Gonocoxite 2 of ovipositor ( Fig. 42) scimitar-shaped, abruptly bent to the outer side at apical third; length approximately six times as basal width; outer margin with three dorsolateral ensiform setae, the basal one finer than the rest two; inner margin with one doromedial ensiform seta near apex.
Etymology. The name elegans refers to the beautiful metallic color of this new species.
Habitat. In southeast Tibet, this species occurs in montane rain forests, with the dominant trees being Castanopsis spp., Machilus spp., and Elaeocarpus spp. Elevation ranges between 1300 and 1850 m. Adults were collected on/in dead tree trunks, or attracted by light.
Remarks. According to the original description (Louwerens, 1964), P. aeneipennis from Borneo has only three setigerous pores on the third elytral interval and seems to be very similar to the new species P. elegans. However, we infer that Louwerens' species has four pores, as he either missed the last pore which is very close to elytra apex or confused it with the umbilical series, same as other species illustrated in the same paper (P. longicollis, P. quadrimaculatus. for example). Moreover, from the original description and illustration, in spite of the pores on the third elytral interval and coloration, P. aeneipennis is very similar to P. cicindeloides which is also recorded in Borneo. We suspect these two species could be conspecific. Unfortunately, no determined material of P. aeneipennis from Borneo was available. Therefore, these two species are retained in their present status, but P. aeneipennis is not included in the key to species. Nevertheless, according to those diagnostic characters mentioned above, the new species P. elegans is quite different from P. aeneipennis. Andrewes, 1937 Figs 6, 29, 40, 47, 58 Diagnosis. Medium size in the subgenus, body length 9.4-10.0 mm; dorsal surface black, elytra without metallic hue; anterior patch zigzag, five intervals wide, in the third to seventh intervals; posterior patch separate, composed of four small spots, in intervals 2-3, 4-5, 6, and 7-8 respectively. Pronotum transverse, PW/PL 1.56-1.65; lateral margins strongly sinuate before posterior angles. Elytral apex slightly curved, outer apical angles rounded; sutural angles blunt; third interval with four setigerous pores, the middle two at approximately anterior two-fifth and two-third; ninth interval with sparse fine setae. Median lobe of aedeagus strongly sinuate on ventral margin.

Pericalus (s. str.) amplus
Comparison. Only three species in the subgenus have four setigerous pores in the third interval of the elytra, but the other two species P. cicindeloides and P. fascinator have no yellowish patches on the elytra. This species is very similar to P. obtusipennis in elytral pattern. For more detailed comparisons between them, see remarks of the latter species (p. 38).
Supplemental description. Male genitalia (Fig. 40). Median lobe of aedeagus fine, abruptly bent after base, forming a distinct angle on the ventral margin; ventral margin strongly sinuate near middle, dorsal margin concaved near base; apical orifice opened to the left; apical lamella small, a little flat, gradually narrowed to apex, slightly bent dorsally in lateral view; endophallus with fine scales only on basal half, without spines. Female genitalia. Internal reproductive system (Fig. 58): spermatheca pedunculate, inserted on the joint of common oviduct and bursa copulatrix; spermathecal body fusiform, apex pointed, longer than the pedicel, distinctly bent; spermathecal gland inserted on the joint of spermathecal pedicel, apex shortly dilated, approximately twice as long as spermatheca. Gonocoxite 2 of ovipositor (Fig. 47) scimitar-shaped, abruptly bent to the outer side at apical fifth; length approximately five times basal width; outer margin with three dorsolateral ensiform setae, the basal one finer than and a little distant from the other two; one doromedial ensiform seta near apex.
Comparison. The new species is very similar and close to P. ornatus, but can be distinguished by male genital characters: (1) in P. acutidens, the apical orifice of aedeagus is much smaller and opened exactly to the left side of median lobe; larger and opened to the left-dorsal side in P. ornatus; (2) in lateral view, median lobe of aedeagus a little narrower and less bent in the new species than in P. ornatus; (3) the apical lamella is a little narrower and longer in P. acutidens; (4) in ventral view, apical lamella of P. acutidens is almost straightly pointed to apex; in P. ornatus, the apical lamella is slightly bent to the right.
Externally, these two species are different in: elytral outer apical angles generally acuminate, projected outwards, forming short tooth in P. acutidens (Fig. 21); not or less pointed, acute, obtuse, or rarely rounded in P. ornatus (Figs 22-26). P. acutidens is also different from P. o. ornatus in elytral anterior patch usually a little transverse (versus usually nearly round), and from P. o. formosanus in elytral third interval with three setigerous pores (versus usually two pores). Generally, the difference on elytral outer apical angles well distinguishes these two species for specimens from China. But in S. Vietnam, both species have the outer apical angles acuminate or acute (Figs 1-4, 6-7 in Fedorenko, 2017). Thus the differentiation of them through external characters can be difficult sometimes. For specimens from China, it is easier to diagnose P. acutidens n. sp. from P. ornatus by their allopatric distributions (Fig. 59), but they are sympatric in at least S. Vietnam.
The new species is sympatric with P. obtusipennis and P. amplus in SW. Yunnan, and they all have similar elytral patterns. From the latter two, P. acutidens can be easily distinguished by the acuminate elytral apical outer angles and the elytral posterior patches which do not have a separate small spot on the sixth interval.
Description. Body length 9.2-12.0 mm. Coloration. Dorsal surface black, elytra with faint cyan metallic hue, with yellowish patches; mouthparts, antennomeres 2-11 reddish brown; legs blackish, tarsus reddish brown; ventral side black. Elytral anterior patch round in form, generally a little transverse and zigzag, in the fourth to sixth intervals, sometimes also in parts of the third and seventh. Elytral posterior patch divided into three small spots, usually in intervals 2-3, 4-5, and 7 respectively; occasionally the first one only on the third interval, the second one only on the fifth interval or on the fourth, fifth, and sixth intervals. Microsculpture faint and nearly isodiametric on vertex and pronotal disc, strong and linear on elytral intervals. Head densely wrinkled; three or four wrinkles on each side extending from clypeus to frons; seven to ten fine wrinkles along each side of inner margin of eye, reaching level of posterior margins of eyes; wrinkles very weak on vertex, occiput almost smooth. Eyes strongly prominent; temporae gradually constricted after eyes. Pronotum strongly transverse, PW/PL = 1.52-1.61, subequal to the width of head with eyes (PW/HW = 0.96-1.02); posterior margin subequal to the width of anterior margin; lateral margins rounded in the middle, distinctly sinuate before posterior angles; posterior angles nearly rectangular, apex sharp, not projecting laterally; lateral expansions wide and rugose; disc a little convex, with fine wrinkles, with a pair of shallow pits on each side; sub-anterior impression barely visible, median line fine, not reaching anterior nor posterior margin; basal fovea shallow, extending medially merged with the shallow sub-posterior impression, extended posteriorly forming very shallow short oblique grooves. Elytra ovate, weakly convex; EW/EL = 0.65-0.73; much wider than pronotum, EW/PW = 1.50-1.65; apical truncation distinctly curved; outer apical angles generally acuminate, or rarely acute; sutural angles blunt; striae moderately incised, without punctures; third interval with three setigerous pores, the first one at approximately basal eighth, the second one at approximately middle, the third one close to apex; the first one adjacent to the third stria, the other two close to the second stria; intervals slightly convex, the eighth interval tumid apically, the eighth and ninth interval with sparse fine setae aside of umbilical series; lateral expansions narrowly extended, a little widened near basal third. Male genitalia (Fig. 37). Median lobe of aedeagus slender and bent, weakly sinuate in ventral and dorsal view; in lateral view, ventral margin evenly curved in the middle; apical orifice small, opened to the left; apical lamella narrow and long, sides parallel in ventral view, in lateral view gradually narrowed to apex, length near two times the basal width, apex rounded; endophallus simple, with very fine scales all through length, without spines. Right paramere with apex extended and expanded, round in form. Female genitalia. Internal reproductive system (Fig. 56): spermatheca pedunculate, inserted on the base of common oviduct; spermathecal body fusiform, longer than the pedicel, distinctly bent; spermathecal gland inserted on the joint of spermathecal pedicel, apex not dilated (probably spermathecal gland apex missing), close to the length of spermatheca. Gonocoxite 2 of ovipositor (Fig. 45) scimitarshaped, abruptly bent to the outer side at apical third; length approximately six times basal width; outer margin with three or four dorsolateral ensiform setae, the basal one finer than the other ones; inner margin with one doromedial ensiform seta near apex.
Etymology. The name acutidens comes from Latin, referring to the generally acuminate elytral outer apical angles of the new species.
Habitat. According to the collecting data, this new species prefers tropical forests with the elevational range between 1000m and 1500m. Adults were collected on/in dead tree trunks, or attracted by light at night.
Remarks. This new species was recorded by Fedorenko (2017) as P. formosanus in south Vietnam. Based on the figures of male genitalia in Fedorenko (2017), we determined that his Vietnam P. formosanus is not the true P. formosanus of Dupuis, but is exactly identical to our new species.
From the examined materials in the present study, the new species is strictly allopatric with P. ornatus in China. The natural boundary in China between them seems to be the Salween River (Fig. 59). But we didn't examine any material form regions between the Salween River and Mekong River. These two species are sympatric in south Vietnam, and the new species is rarer than P. ornatus (Fedorenko, 2017).
Pericalus ornatus was previously recorded from North India (Assam, Sikkim, Garo Hills), Myanmar (North Shan States, Karin Chebà), Thailand, Laos, and Cambodia. We doubt some of these records are actually P. acutidens sp. n. The record from North Shan States (Andrewes 1923) is very close to Ruili (Yunnan) where P. acutidens sp. n. was recorded and P. ornatus does not occur. Thus this record should be confirmed to P. acutidens sp. n. According to the confirmed records (solid spots in Fig. 59) we inferred that these two species could be sympatric in S. Laos, S. Myanmar, Thailand, and Cambodia, and P. ornatus may not occur in N. India and N. Myanmar. The records from north India (Andrewes 1923) may refer to P. acutidens sp. n. or some other unknown species (empty red circles in Fig. 59). Schmidt-Göbel, 1846 Figs 9, 10, 11, 16, 22, 23, 24, 38, 48, 51, 59 (Fig. 16). Diagnosis. Medium size in the subgenus, body length 8.4-12.5 mm; dorsal surface black, elytra usually with faint cyan hue; anterior patch usually nearly round, three to five intervals wide; posterior patch separate, composed of three small spots, in intervals 2-3, 4-6, and 7 respectively, the middle one variable, when narrowest, present on the fifth interval only. Pronotum transverse, PW/PL 1.53-1.63; lateral margins sinuate before posterior angles, posterior angles nearly rectangular; disc with fine wrinkles. Elytra flat; apical truncation distinctly curved; outer apical angles usually acute (Figs 22, 24), sometimes obtuse (Fig. 23) or acuminate (in S. Vietnam); sutural angles blunt; third interval with three setigerous pores, the second one near middle of elytron. Median lobe of aedeagus with apical orifice large, opened to left-dorsal side (Fig. 38).

Pericalus (s. str.) ornatus ornatus
Comparison. P. o. ornatus is distinguishable from similar taxa by the acute or obtuse elytral outer apical angles and elytral anterior patch usually round. P. o. ornatus is sympatric with P. obtusipennis and P. amplus in China, and all have similar elytral pattern. From the latter two species, P. ornatus can be easily distinguished by the elytral apical outer angles not rounded and without separate spot on the sixth interval. (Fig. 38). Median lobe of aedeagus slender and bent; in lateral view, ventral margin evenly curved in the middle; in ventral view, right margin barely sinuate near middle, apical lamella slightly bent to the right; apical orifice larger than P. acutidens, opened to left-dorsal side; apical lamella small, side paralleled in ventral view, in lateral view gradually narrowed to apex, length a little greater than the basal width, apex rounded; endophallus with very fine scales on some regions, without spines. Female genitalia. Internal reproductive system (Fig. 51): spermatheca pedunculate, inserted on the joint of common oviduct and bursa copulatrix; spermathecal body fusiform, a little longer than the pedicel, distinctly bent; spermathecal gland inserted on the joint of spermathecal pedicel, apex dilated, much longer than spermatheca. Gonocoxite 2 of ovipositor (Fig. 48) scimitar-shaped, abruptly bent to the outer side at apical fourth; length approximately six times as basal width; outer margin with three dorsolateral ensiform setae, the basal one a little distant from the other two; inner margin with one doromedial ensiform seta near apex.
Remarks. We attribute above specimens to P. ornatus based on the descriptions (Schmidt-Göbel 1846; Andrewes 1923) and a photograph of one syntype we took in NMPC years ago (Figs 9, 16). The syntype of P. ornatus has an almost round elytral anterior patch and the outer apical angles acute, not acuminate. It is agrees perfectly with the examined materials from southeast Yunnan and Tonkin. They are quite probably the same species, although the genitalia of syntype were not studied.
Diagnosis. Medium size species, body length 9.5-10.5 mm; dorsal surface black, elytra usually with faint cyan hue; anterior patch transverse, a little zigzag (more transverse and zigzag than P. o. ornatus), usually in the fourth to sixth intervals; posterior patch separate, composed of three small spots, in intervals 2-3, 4-5, and 7 respectively. Pronotum transverse, PW/PL 1.50-1.58; lateral margins sinuate before posterior angles, posterior angles nearly rectangular; disc with fine wrinkles. Elytra flat; apical truncation distinctly curved; outer apical angles usually obtuse (Fig. 25), occasionally rounded (Fig. 26) or acute; sutural angles blunt; third interval usually with two setigerous pores (occasionally three as other species), the middle one usually missing. Median lobe of aedeagus with apical orifice opened to left-dorsal side (Fig. 39).
Comparison. This subspecies is different from the nominate subspecies in: (1) elytral anterior patch generally more or less transverse (width a little more than length), and somewhat zigzag in P. o. formosanus (Fig. 12); nearly round (width subequal to the length) and not zigzag in P. o. ornatus (Figs 9-11).
(2) P. o. formosanus generally with only two setigerous pores on the third elytral interval (occasionally three); in P. o. ornatus always with three setigerous pores; (3) in P. o. formosanus, the elytral outer apical angles obtuse in most examined specimens (Fig. 25); in P. o. ornatus usually acute (Figs 22, 24). But for some individuals, the shape of elytral outer apical angles cannot differentiate these two subspecies. The male genitalia of these two subspecies have no significant differences (Figs 38, 39).
Pericalus o. formosanus is very similar with P. acutidens in elytra pattern, but can be distinguished by two pores on elytral third interval, different male genitalia, and distribution. This subspecies is endemic and the only Pericalus species in Taiwan.
Remarks. According to our examined specimens, the male genitalia of P. formosanus have no significant differences from those of P. ornatus from the Asian continent. Considering the external differences between P. ornatus as well as their allopatric distributions, it is preferable to assign P. formosanus as a subspecies of P. ornatus rather than synonymize them. Fedorenko (2017) recorded P. formosanus from S. Vietnam based on a misidentification of P. acutidens sp. n.

Material examined
Comparison. This species is most similar with P. obscuratus sp. n. in the genus. For comparisons between them, see Comparison section of that new species. Pericalus obtusipennis is also very similar to P. distinctus from India and Myanmar. Detailed discussions on these two species are provided below.
Pericalus obtusipennis might be confused with P. ornatus or P. acutidens due to their similar elytra pattern and sympatric distribution. But P. obtusipennis is different from the latter two species in several external characters: (1) elytral outer apical angles rounded in P. obtusipennis; acuminate, acute or obtuse in other two species; (2) elytral anterior patch zigzag in P. obtusipennis, always very narrow and strongly transverse (similar to that in P. acutidens); but rounded or nearly rounded in P. ornatus, rarely somewhat zigzag, but wider; (3) in P. obtusipennis, elytral posterior patches always with a separate small spot on the sixth interval, placed much beyond to that in the fourth and fifth intervals (Fig.  15); in the other two species, spot in sixth interval usually absent (Figs 9, 10); if present, adjacent to the larger spot in the fourth and fifth interval (Figs 11,12); (4) all three species with very faint metallic hue on elytra, but cupreous in P. obtusipennis and cyan in the other two species. Moreover, P. obtusipennis has the median lobe of the aedeagus strongly dilated, very different from those of all other known species.
From the elytral pattern and outer angle, P. obtusipennis is also similar to P. amplus with which it is sympatric with in Yunnan and N. Vietnam. These two species can be distinguished by: (1) P. obtusipennis with three setigerous pores in elytral third interval; P. amplus with four pores; (2) wrinkles along inner margin of eyes a little coarser and sparser in P. obtusipennis, with 7-8 wrinkles on each side; a little finer and denser in P. amplus, with 9-10 wrinkles on each side; (3) elytra a little more convex in P. amplus; (4) male genitalia very different (Figs 35, 40).
Supplemental description. Male genitalia (Fig. 35). Median lobe of aedeagus rather stout, total length / greatest width approximately 3.7 (in lateral view), strongly dilated after basal bend, and abruptly narrowed before apical lamella; ventral margin nearly straight in the middle, dorsal margin evenly curved; apical orifice large, reaching one third length of the median lobe, opened to the left; apical lamella small, digitiform, length approximately 1.5 times as basal width; endophallus with fine scales all through length, without spines. Female genitalia. Internal reproductive system (Fig.  50): spermatheca pedunculate, inserted on the joint of common oviduct and bursa copulatrix; spermathecal body fusiform, longer than the pedicel; spermathecal gland inserted on the joint of spermathecal pedicel, apex shortly dilated. Gonocoxite 2 of ovipositor ( Fig. 49) scimitar-shaped, abruptly bent to the outer side at apical fourth; length approximately six times as basal width; outer margin with four dorsolateral ensiform setae, the basal one much finer than the other three; inner margin with one doromedial ensiform seta near apex.
Distribution. Vietnam (Lao Cai), China (Yunnan) (Fig. 60). This species is sympatric with P. acutidens sp. n. in west Yunnan, but seems to prefer a higher elevation (1700-2000 m) and is much rarer.
Remarks. The little known species P. distinctus Dupuis, recorded from India and Myanmar, is very similar to P. obtusipennis. From the very brief original description (Dupuis 1913) and comments added later (Andrewes 1937), diagnostic characters of P. distinctus can be summarized as follows: elytral outer apical angles rounded or obtuse; elytral anterior patch composed of a transverse band, in intervals third to sixth, slightly obliquely backwards on each side; posterior patch similar to that of P. ornatus; third interval with three setigerous pores; legs and antennae pale reddish brown, much lighter than P. ornatus. Most of these characters agree with those of P. obtusipennis, except for pale legs and antennae. We did not examine any confirmed material of P. distinctus in the present study and cannot compare it with P. obtusipennis further. But, with the very distinctive male genitalia, our examined specimens from Yunnan can be readily identified as P. obtusipennis. Diagnosis. Medium size, body length 9.9-11.5 mm; dorsal surface black, elytra with very faint cyan hue; anterior patch zigzag, three to five intervals in width, when widest, in the third to seventh intervals; posterior patch separate, composed of four small spots, in intervals 2-3, 4-5, 6, and 7; pronotum transverse, PW/PL 1.60-1.75; lateral margins barely sinuate before posterior angles; elytral outer apical angles rounded, sutural angles blunt; third interval with three setigerous pores; median lobe of aedeagus a little dilated.

Pericalus
Comparison. This new species is very similar to P. obtusipennis. It can be distinguished from the latter species by: (1) all elytral yellowish patches smaller than P. obtusipennis, most of patches equal or shorter than the interval width in P. obscuratus sp. n., usually longer than the interval width in P. obtusipennis; (2) elytra with very faint cyan metallic hue; with faint cupreous hue in P. obtusipennis; (3) pronotum usually wider (PW/PL = 1.60-1.75) than in P. obtusipennis (PW/PL = 1.55-1.60); (4) pronotal lateral margins barely sinuate before posterior angles (versus slightly but distinctly sinuate); (5) in P. obscuratus sp. n., median lobe of aedeagus only a little dilated, in lateral view total length / greatest width approximately 4.8 (Fig. 36); strongly dilated in P. obtusipennis, total length / greatest width approximately 3.7 (Fig. 35). In spite of the above characters, these two species are almost identical, but their different male genitalia support that they are distinct species.
Description. Body length 9.9-11.5 mm. Coloration. Dorsal surface black, elytra with very faint cyan hue, with yellowish patches; mouthparts, antennomeres 2-11 reddish brown; legs dark brown, tarsi yellowish brown; ventral side black. Elytral anterior patch zigzag, in the third to seventh intervals, pale markings in the third and seventh intervals sometimes faint; pale markings in odd intervals anteriorly placed, those in even intervals posteriorly placed; the zigzag patch narrow and a little oblique, usually subequal to single interval width, pale marking in the fifth interval a little anterior to that in the third. Elytral posterior patch separate, composed of four small spots in intervals 2-3, 4-5, 6, and 7; each spot usually shorter than single interval width; from anterior to posterior, the order of four spots: 6, 4-5, 7, 2-3. Microsculpture faint and isodiametric on vertex and pronotum disc, distinct and linear on elytral intervals. Head densely rugose; three to five shallow wrinkles on each side extending from clypeus to frons; eight to ten fine wrinkles along each side of inner margin of eye, reaching level of posterior margin of eyes; vertex and occiput almost smooth. Eyes strongly prominent; temporae gradually constricted behind eyes. Pronotum strongly transverse, PW/PL = 1.60-1.75, sub-equal to the width of head with eyes (PW/ HW = 1.00-1.11); posterior margin close to the width of anterior margin; lateral margins rounded in the middle, very weakly sinuate before posterior angles; posterior angles nearly rectangular, not or weakly projecting laterally, with a seta very close to the posterior angles; lateral expansions wide; disc weakly convex, nearly smooth, with very faint wrinkles, with a pair of very shallow pits on each side; sub-anterior impression barely visible, median line fine, not reaching anterior nor posterior margin; basal fovea shallow, extended medially merged with the shallow sub-posterior impression, extended posteriorly forming very shallow short oblique grooves. Elytra ovate, weakly convex; EW/EL = 0.72-0.74; much wider than pronotum, EW/PW = 1.51-1.63; apical truncation weakly curved; outer apical angles rounded, sutural angles blunt; striae moderately incised, impunctate; third interval with three setigerous pores, the first one at approximately basal eighth, the second at approximately apical two fifth, the third one close to apex; the first one adjacent to the third stria, the other two close to the second stria; intervals slightly convex, the eighth interval tumid apically, the eighth and ninth intervals with sparse fine seta aside of umbilical series; lateral expansions narrowly extended, a little widened near basal third. Male genitalia (Fig.  36). Median lobe of aedeagus a little dilated, total length / greatest width approximately 4.8 (in lateral view), gradually narrowed before apical lamella; ventral margin unevenly curved near middle, dorsal margin evenly curved; apical orifice large, reaching one fourth length of the median lobe, opened left-ventrally; apical lamella small, gradually narrowed to apex, length approximately 1.5 times as basal width; endophallus with fine scales all through length, without spines. Right paramere with apex extended and enlarged, securiform. Female genitalia. Internal reproductive system (Fig. 55): spermatheca pedunculate, inserted on the joint of common oviduct and bursa copulatrix; spermathecal body digitiform, longer than the pedicel, distinctly bent; spermathecal gland inserted on the joint of spermathecal pedicel, apex not dilated (probably spermathecal gland apex missing), nearly same length as spermathecal body. Gonocoxite 2 of ovipositor ( Fig. 44) scimitar-shaped, abruptly bent to the outer side at apical fifth; length approximately six times as basal width; outer margin with three dorsolateral ensiform setae, the basal one finer than and a little distant from the rest two; inner margin with one dorsomedial ensiform seta near apex.
Etymology. This name obscuratus means indistinct, referring to the elytral pattern of this new species which is much narrower than those of all other allied species, almost indistinct.
Habitat. In Fanjingshan, this species occurs in evergreen and deciduous broadleaved mixed forests, with dominant trees of Cyclobalanopsis spp. and Fagaus spp., with an elevational range of 1775 to 2078 m. Adults were collected on or under bark of dead trees during the night.