Two new species of the genus Cyanopenthe Nikitsky, 1998 (Coleoptera, Tetratomidae) from southwest China

Abstract The genus Cyanopenthe Nikitsky, 1998 is first recorded from mainland China. Two new species, C. granulatasp. nov. and C. hirtiscutellarasp. nov., are described and illustrated. This genus is redefined, and an updated key to the known species is presented.

The genus Cyanopenthe Nikitsky, 1998 belongs to the subfamily Penthinae Lacordaire, 1859 and contains only four described species in the world (Champion 1916;Ni-kitsky 1998;Hsiao et al. 2015). Penthe metallica Champion, 1916 was described based on single female without locality data. Another two female specimens were discovered from northern India and Bhutan (Nikitsky 2005;Hsiao et al. 2015). Subsequently, a revision of the family Tetratomidae was contributed by Nikitsky (1998). In this work, a new genus, Cyanopenthe Nikitsky, 1998, was established and compared with the genus Penthe Newman, 1838; Penthe metallica Champion, 1916 was designated as the type species of this new genus, and one new species, C. thailandcia Nikitsky, 1998, was described. The latter was similarly based on a single female from northwestern Thailand with only a line drawing habitus of the holotype. A line drawing habitus of the holotype of C. metallica (Champion, 1916) was also provided by Nikitsky (1998). In 2005, a detailed key to the Cyanopenthe species was given by Nikitsky with corresponding figures that including the ovipositor of the holotype of C. thailandica Nikitsky, 1998. In a recent work by Hsiao et al. (2015), two new species, C. taiwana Hsiao et al., 2015 andC. leei Hsiao et al., 2015, were described based on both sexes with color habitus from Taiwan of China, as well as the female ovipositor and the male genitalia; the female ovipositor of C. metallica (Champion, 1916) was also presented for the first time, along with a supplementary description, and a key to all species of the genus was provided.

Materials and methods
The specimens were examined and dissected under a Nikon SMZ800 microscope. Photographs of adult habitus were taken with a Canon EOS 5D Mark III connected to a Canon MP-E 65 mm macro lens. Photographs of other morphological details were taken using a Leica M205A stereomicroscope. Adobe Photoshop 7.0 software was used in image processing. The aedeagus and ovipositor were detached from the body with insect needles, then glued to separate cards and pinned under the specimens. Specimens examined in this study are deposited in MHBU (Museum of Hebei University, Baoding, China) and IZCAS (Institute of Zoology, Chinese Academy of Sciences, Beijing, China). A double slash (//) separates data of different labels.
Body length was measured from the anterior margin of the clypeus to elytral apex; the terminology of the ovipositor follows Hsiao et al. (2015); absolute measurements are indicated in millimeters (mm). Pronotum either densely and coarsely punctured throughout or granulate posteriorly with coarse punctures on anterior half of pronotal disc; antennomere V evidently longer than VI in female ( Dorsal side of body blue-violet; pronotum densely granulate, except coarsely punctured in anterior half of disc; scutellum yellow; lateral margins of paraproct of ovipositor somewhat straighter, proctiger almost as long as gonocoxites, gonostylus with long setae ( Diagnosis. Body black, shining, with dark metallic blue or green-blue, covered with dense and black erect pubescence. Head small, dorsal surface with narrow, longi-tudinal median depression. Eyes lateral, large and protruding. Antennae long, antennomeres VIII-XI (♂) or VII-XI (♀) strongly broadened into a pectinate club. Pronotum transverse, disc weakly convex, flattened laterally with pair of large impressions near base. Prosternal process strongly broadened posteriorly and somewhat roundly truncate apically, slightly exceeding the posterior margin of prothoracic coxae. Scutellum large, triangular or transverse, covered with dense and decumbent yellow to reddish, bronzed pubescence, with or without dark rounded impression at middle. Elytra broadly oval, much wider than pronotum, disc convex, depressed from middle to humeri along lateral margins. Legs slender and long, underside of metafemora with [or maybe without (not mentioned in the previously described species)] dense yellow hairbrush from base to middle in male, metatarsomere I shorter than the remaining tarsomeres combined.

Key to species of the genus
Aedeagus ensiform, parameres slightly shorter than or as long as phallobase. Distal part of parameres divergent in dorsal and ventral view, curved to ventral side in lateral view.
Ovipositor flattened, paraproct elongated, lateral margins subparallel, straight or weakly curved; proctiger semicircular in dorsal view, tapered posteriorly and more or less curved in ventral view.
Distribution. Bhutan, China (Taiwan, Xizang, Yunnan), India, and Thailand. Diagnosis. This species is similar to C. metallica (Champion, 1916), but can be distinguished by the following characters (based on females): dorsal side of body greenblue; antennomere V nearly as long as VI; densely granulate on pronotum; scutellum bronzed; elytral surface with large punctures nearly in rows; posterior margin of abdominal ventrite V more broadened; paraproct of ovipositor more elongate (1.7 times as long as wide), lateral margins weakly curved.
Description. Dorsal side of body royal blue, antennae, femora, tibiae and ventral side of body dark blue, some of sternum and abdomen blue-green. Scutellum bronzed, bordered with distinct blue-violet metallic sheen on elytra. Body with dense and black erect pubescence dorsally as well as ventrally. Scutellum with dense and decumbent orange pubescence. Underside of metafemora densely with yellow hairbrush from base to middle in male. Male (Figs 1, 3, 5-8, 10-13). Head small, length 1.0 mm, width 1.5 mm, densely and finely punctured, dorsal surface with narrowly, longitudinal median depression. Eyes lateral, large and protruding, ratio of eye diameter to interocular space 1.0: 1.9. Maxillary palpomere II elongate-triangular, III suborbiculate, IV obliquely rounded at apex, sides subparallel, surface of extend part somewhat rough and dull, no shining. Antennae (Fig. 3) length 3.8 mm, antennomere I cylindrical, II suborbiculate, III strongly elongate and somewhat clavate, IV-VI clavate, VII somewhat broadened into a pectinate club, approximately as long as projection, VIII-XI strongly broadened into a pectinate club, projections 1.7 times longer than wide; ratio of antennomere lengths as follows: 3.0: 2.0: 6.0: 4.0: 3.2: 2.5: 2.0: 3.2: 3.4: 3.7: 2.8. Pronotum (Fig. 5) transverse, length 1.2 mm, width 2.6 mm, 1.7 times as wide as head. Disc weakly convex, flattened laterally with pair of large impressions extending from base to approximately 1/3 length of pronotum. Surface with dense granules, separated by less than their diameter. Anterior margin slightly sinuate, posterior margin sinuate; lateral margins widest at anterior angles and narrowing posteriorly. Anterior angles rounded, posterior angles rectangular. Prosternal process strongly broadened posteriorly and somewhat roundly truncate apically, slightly exceeding posterior margin of prothoracic coxae. Scutellum (Fig. 5) large, triangular, 1.1 times as wide as long; surface densely and finely punctate, without dark rounded impression centrally.
Elytra broadly oval, length 6.4 mm, width 4.0 mm, much wider than pronotum. Disc convex, depressed from middle to humeri along lateral margins. Surface with tiny punctures, and large punctures nearly in rows medially on each elytron. Diameter of punctures in spaces between striae 1.7 times smaller than that of punctures in rows.
Etymology. This species is named from the Latin granulus, referring to the densely granulose pronotum.
Bionomics. The holotype was found on a dead wood with fungi of Polyporaceae in the forest (Fig. 24). The paratype was found on a stump of poplar.
Remarks. The variation of color in male and female could be caused by fading or differences between male and female individuals; we are not sure. The aedeagus of the holotype and the ovipositor of the paratype are somewhat damaged.
Diagnosis. This species is closely related to C. granulata sp. nov. and C. metallica (Champion, 1916), but can be distinguished by the following characters (based on female): dorsal side of body blue-violet; pronotum densely granulate, except coarsely punctured in anterior half of disc; scutellum yellow; lateral margins of paraproct of ovipositor nearly straight, proctiger almost as long as gonocoxites, gonostylus with long setae.
Description. Dorsal side of body blue-violet, antennae, femora, tibiae and ventral side of body dark blue, some individuals with sternum and abdomen blue. Scutellum yellow, around scutellum with distinct dark-blue metallic sheen on elytra. Body with dense and black erect pubescence, dorsally and ventrally. Scutellum with dense and decumbent yellow pubescence.
Elytra broadly oval, length 7.4 mm, width 5.0 mm, much wider than pronotum. Disc convex, depressed from middle to humeri along lateral margins. Surface with tiny punctures and irregular large punctures.
Etymology. This species is named from the Latin hirtus and scutella, in reference to the dense decumbent pubescence on the scutellum.

Discussion
As far as we know, Cyanopenthe species inhabit moist and warm forest habitats, and feed on fungi of Polyporaceae at night in small aggregations or alone; all known species occur in Bhutan, China (Taiwan, Xizang, Yunnan), northern India and northwestern Thailand of Southeast Asia. We believe that more species may be discovered in the Himalayas, Myanmar, Laos, Vietnam and Southern China in the future.