Pterostichus (Circinatus) yan, Shi, Hongliang & Liang, Hongbin, 2015

Shi, Hongliang & Liang, Hongbin, 2015, The genus Pterostichus in China II: the subgenus Circinatus Sciaky, a species revision and phylogeny (Carabidae, Pterostichini), ZooKeys 536, pp. 1-92 : 23-25

Taxon classification Animalia Coleoptera Carabidae

Pterostichus (Circinatus) yan sp. n. Figures 15, 31, 101

Type locality.

Hubei: Shennongjia, Muyu (ca. N31.47°, E110.39°), altitude 2000 m.

Type material.

Holotype (NHMB): male, body length = 12.8 mm, board mounted, genitalia dissected and glued on plastic film pinned under specimen, "CHINA, W HUBEI prov. / Dashennongjia Nat. Res. / Muyu, E slope, 2000 m / 12-15 Jun 1997, Bolm. lgt."; "HOLOTYPE ♂/ Pterostichus (Circinatus) / yan new species / des. SHI H.L. 2015" [red label].

Diagnosis.

Pronotum with single mid-lateral seta; posterior seta close to hind angle; hind angle nearly rounded; elytron with microsculpture hardly visible, linear; males with two small tubercles on terminal sternum; fifth tarsomeres glabrous beneath. For comparisons between similar species see table 1 under Pterostichus maitreya .

Description.

Body form slightly elongate, relatively larger-sized species within subgenus, body length 12.8 mm; dorsal side blackish, moderately shining, elytron with distinct iridescent shine; mouthparts, antenna, tarsus, tibia, and apex of femur reddish brown; ventral side blackish. Elytral microsculpture very faint, linear. Head. Frons without punctures; antenna reaching elytron basal fifth; gena shorter than length of eye, briefly tumid behind eye. Pronotum nearly round, lateral margin strongly curved, widest a little before middle; posterior margin narrower than anterior margin; PW/PL = 1.15; one mid-lateral seta present, at approx anterior third; posterior seta very close to hind angle; hind angle nearly rounded, not forming obtuse angle; basal fovea shallow, faintly defined; inner groove subparallel to median line, basal half slightly oblique outwards; outer groove indistinct; outer area of inner groove slightly depressed; basal foveal area distinctly punctate. Elytron oviform, with basal ridge almost straight; elytral shoulder moderately widened, shoulder angle between basal ridge and lateral margin forming obtuse angle, humeral tooth very small, a little pointed; intervals feebly convex; striae moderately deep, without punctures; scutellar stria short, apex free; third interval with two setigerous pores adjacent to second stria; umbilical pore series on ninth interval sparse in middle, composed of 16-17 pores (6-7, 2, 8). Ventral side. Proepisternum impunctate, mesepisternum and metepisternum densely punctate; male terminal sternum with two small tubercles, tubercles indistinctly defined, a little before middle of sternum, region between tubercles slightly depressed. Legs. Fifth tarsomeres glabrous beneath; males with apical half of mesotibia widened, inner margin crenulate; first two metatarsomeres with distinct carina on outer surface, such carina on basal half of third metatarsomere superficial. Male genitalia. Median lobe of male genitalia bent approx 90 degrees, apex slightly bent ventrally (Fig. 31A); ventral margin straight in middle, turned ventrally near apex; dorsal margin gradually curved; apical orifice large, slightly turned to left side, opened on ventral side; in lateral view, apical lamella short and slightly sinuate, laminate with base slightly thickened, not twisted, its length approx one eighth length of apical orifice; in dorsal view, apical la mella located on right side of aedeagal apex, pointing apical-ventrally, slightly oriented to left side; apical lamella nearly triangular, gradually narrowed to apex, apex rounded, its base distinctly grooved on dorsal surface; length of apical lamella approx 1.1 times its basal width (Fig. 31B). Right paramere straight and stout, nearly triangular, apical half slightly enlarged, strongly narrowed and slightly hooked to apex; length approx 2.8 times greatest width, apex pointed (Fig. 31C). Endophallus not studied. Female genitalia unknown.

Distribution.

This species is known only from the holotype collected from Shennongjia in Hubei Province (Map 1). The altitude is approx 2000 m.

Etymology.

This new species is named for Emperor Yan, also called Shennong, who was a mythical emperor in ancient China, and generally regarded as one of the ancestors of all Chinese nations. The place Shennongjia (a mountain in west Hubei province, the type locality of this new species) is named for Emperor Yan as well.

Affinities.

Pterostichus yan sp. n. is close to Pterostichus baenningeri , Pterostichus maitreya sp. n., Pterostichus ailaoicus sp. n., and Pterostichus miao sp. n. in their similarities of male terminal sternum and male genitalia.