Two new species of Micrencaustes Crotch, subgenus Mimencaustes Heller from China (Coleoptera, Erotylidae, Encaustini)

Abstract Two new species Micrencaustes (Mimencaustes) renshiae sp. n. and Micrencaustes (Mimencaustes) biomaculata sp. n. are described and illustrated from China. A key to Chinese species of subgenus Mimencaustes Heller is provided.


Material and methods
The specimens examined in this paper were collected in a wide variety of woodland fungus, in crevices under bark or in other retreats by splitting and sifting. They were killed with ethyl acetate and dried. For an examination of the male or female genitalia, the abdominal segments were detached from the body after softening in hot water. Morphological figures were prepared using a Nikon SMZ1500 stereomicroscope; habitus photos were taken with a Nikon D7000 camera. All measurements are given in millimeters. The specimens treated in this study are deposited in the Museum of Hebei University (MHU), Hebei, P. R. China.
The measurements of proportions are abbreviated as follows: pl/pw -pronotum length/width ratio. Description. Body ( Fig. 1) moderately elongate, length: 10.5-12.4mm, width: 4.1-4.5mm; widest at base of elytra, general color dark, slightly shining. Head with an irregular orange mark between eyes. Pronotum with two longitudinal, curved orange marks, each bearing a short branch in the middle. Head (Fig. 2) strongly and sparsely punctured on vertex, with ocular lines. Clypeus strongly and rather closely punctured, with anterior border feebly emarginate, with a fovea on each side of the base. Eyes large, moderately prominent laterally. Antennae (Fig. 3) extending posterior border of pronotum; antennomere III about 1.75 times as long as IV; antennomere IX asymmetrical, almost triangular; antennomere X bowl-shaped; antennomere XI hemispherical, narrower than antennomere X, slightly constricted in middle; relative lengths of antennomeres . Maxillary palp terminal segment triangular, sides rounded, nearly 2.7 times as wide as long. Mentum ( Fig. 4) with plate triangular, sides concave, with coarse punctures and setae; submentum roughly punctured, with long golden setae. Pronotum (Fig. 5) widest at base (pl/pw = 0.69-0.74); lateral margin slightly curved; pronotal anterior margin straight in the middle; basal margin weakly sinuate. Pronotum finely punctate, punctures evenly scattered; with a group of coarse punctures on each side of base area. Anterior angles projected; posterior angles nearly rectangular. Prosternum (Fig. 6) coarsely and sparsely punctured on lateral areas, with some oblique rugae; an irregular depression in the middle of base area; surface with golden pubescence. Prosternal process triangular, strongly emarginated at apical border, produced into a blunt point at the base. Prosternal femoral lines almost straight, converging anteriorly and reaching the front edge of coxae.
Scutellum pentagonal, with fine and spare punctures. Elytra widest near base, then gradually narrowing to apex. Each elytron with 8 striae; strial punctures stronger at basal part, gradually weakened apically and disappeared before extremity; intervals finely punctured and wrinkled. Mesoventrite (Fig. 7) broad, with a median quadrate depression; mesocoxal lines short; sternum with fine and sparse punctures.
Mesotibia (Fig. 8) with outer edge of apex acutely toothed. Male genitalia (Fig. 9) with median lobe weakly curved; narrowed to a point in lateral view; median strut about 1.31 times as long as median lobe.
Female genitalia (Fig. 10) with narrow styli at apex of coxite, and styli rounded apically, covered with setae at apex. Female spermatheca as in Fig. 11.  Description. Body (Fig. 12) oblong oval, moderately convex, length: 10.8-12.5mm, width: 3.5-4.4mm; general color dark, moderately shining. Each elytron with 2 orange bands; anterior band reaching lateral and basal margins, leaving a black part at humerus, with 2 black spots near anterior border, with 4 teeth at posterior border; posterior band at four fifths length of elytron, extending from the striae I to near the lateral border, with 2 teeth at anterior border, with 3 teeth at posterior border. Head (Fig. 13) sparsely punctured on vertex, closely at base, with ocular lines. Clypeus strongly and closely punctured, with anterior border feebly emarginate, with a fovea on each side of the base. Eyes large, rather prominent laterally. Antennae (Fig. 14) reaching basal 0.25 of pronotum; antennomere III about 1.69 times as long as IV; antennomere IX asymmetrical, almost triangular; antennomere X crescent-shaped; antennomere XI hemispherical, narrower than antennomere X, slightly constricted in middle; relative lengths of antennomeres II-XI: 12: 27: 16: 16: 17: 16: 14: 18: 13: 20. Maxillary palp terminal segment broadly triangular, nearly 3.2 times as wide as long. Mentum (Fig. 15) with plate triangular, sides concave, with rather coarse punctures and setae; submentum roughly punctured, with short golden setae.
Pronotum (Fig. 16) widest at middle (pl/pw = 0.67-0.72); sides almost parallel on posterior half and narrowing toward apex, strongly margined; anterior margin straight in the middle, margined behind eyes; basal margin weakly sinuate. Pronotum finely and sparsely punctuated, with a group of coarse punctures on each side of base area, with punctate longitudinal median areas. Anterior angles projected; posterior angles nearly rectangular. Prosternum (Fig. 17) coarsely and sparsely punctured on lateral areas, with some oblique rugae; an irregular depression in the middle of base area; surface with golden pubescence. Prosternal process triangular, strongly emarginated at apical border, produced into a blunt point at the base. Prosternal femoral lines converging anteriorly and reaching the front edge of coxae.
Scutellum nearly pentagonal, sparely punctured. Elytra widest at base, sides almost parallel at two thirds from base, then gradually narrowing to apex; strial punctures fine at basal part and disappeared before extremity; intervals finely punctured and distinctly wrinkled.
Male genitalia (Fig. 20) with median lobe curved; narrowed to a hook at apex in lateral view; median strut about 1.43 times as long as median lobe.
Female genitalia (Fig. 21) with narrow styli at apex of coxite, and styli rounded apically, covered with setae at apex. Female spermatheca as in Fig. 22.
Distribution. Known only from the type locality (China: Yunnan Province, Eryuan County).
Diagnosis. The new species is most similar to Micrencaustes (Mimencaustes) michioi Osawa & Chûjô, 1990, but can be distinguished from it by body moderately shining; pronotum with anterior margin margined behind eyes, without impunctate longitudinal median areas; mesotibia with outer edge of apex acutely toothed. In Micrencaustes (Mimencaustes) michioi, the body fairly shining; pronotum with anterior margin immarginate, with impunctate longitudinal median areas; every tibia with outer edge of apex acutely toothed.
Etymology. The species is named with 2 black spots near anterior border of basal mark of elytron.