Micrencaustes (Mimencaustes) occulta Yang & Li, 2024

Yang, Yuhang, Zhang, Xiaoxiao, Liu, Jing & Li, Jing, 2024, A new species and two newly-recorded species of the genus Micrencaustes (Coleoptera, Erotylidae) from China, Biodiversity Data Journal 12, pp. e 134304-e 134304 : e134304-

Micrencaustes (Mimencaustes) occulta Yang & Li sp. nov.

Materials

Type status: Holotype. Occurrence: individualCount: 1; sex: 1 male; occurrenceID: E26B1B82-1138-5DBE-BCC0-4B69A840C898; Location: country: China; stateProvince: Yunnan; county: Yingjiang; verbatimCoordinates: 24.691355 ° N, 97.943483 ° E; Identification: identifiedBy: Yibing Ba; Event: year: 2012; month: 8

Diagnosis

Body elongate-oval, convex dorsally, black, moderately lustrous. Each elytron with two orange marks and with seven distinct striae. Clypeofrontal sulcus incomplete. Interocular distance about 0.47 times width of head. Antennae long, almost extending to the posterior edge of pronotum, antennomere 3 long and apex slightly swollen, 1.6 times as long as antennomere 4, antennomere 9 almost equal in length and width; antennomere 10 transverse, 2.1 times as wide as long. Maxillary terminal palpomere transverse, nearly semicircular, 2.8 times as wide as long. Lacinia with two teeth at apex. Pronotum with three indistinct teardrop-shaped orange marks and with a few coarse punctures on each side of base. Postmesocoxal lines absent.

Description

Body length: 13.2 mm; width: 6.2 mm, elongate-oval, convex in lateral view, general colour black, moderately lustrous. Pronotum with three indistinct teardrop-shaped orange marks. Each elytron with two orange marks, the first mark reaching the basal edge and with a wave at posterior edge; the second mark at basal three fourths, transverse and curved, with a wave at anterior edge (Fig. 1 ). Head (Fig. 2 a) coarsely punctured on vertex. Clypeus finely punctured, anterior edge straight. Clypeofrontal sulcus incomplete. Eyes large, coarsely facetted; interocular distance about 0.47 times width of head. Antennae (Fig. 2 b) long, almost extending to posterior edge of pronotum, covered with golden setae; antennomere 1 swollen, barrel-shaped; antennomere 2 spherical; antennomere 3 long, slightly swollen at apex, 1.6 times as long as antennomere 4; antennomere 9-11 transverse and compact, forming the antennal club, antennomere 9 expanded apically; antennomere 10 crescent-shaped, 2.0 times as wide as long; antennomere 11 nearly fan-shaped; relative lengths of antennomeres 2-11: 1.5: 3.6: 2.1: 2.2: 2.3: 2.2: 2.2: 2.8: 2.0: 2.2. Maxillary terminal palpomere (Fig. 2 c) transverse, strongly expanded, nearly triangular, 2.8 times as wide as long. Labial terminal palpomere (Fig. 2 d) dolabriform. Mentum (Fig. 2 e) small, nearly pentagonal, with middle area triangularly depressed; submentum (Fig. 2 e) nearly trapezoidal, with a few coarse punctures in the middle and two extremely coarse punctures at the base.

Pronotum (Fig. 2 f) 2.2 times as wide as long, nearly trapezoidal, convex dorsally, with extremely sparse punctures. Anterior edge curved opposite the head; lateral edge curved, with expressed border and slightly narrowing apically; basal edge weakly sinuate, with a few coarse punctures on each side of base. Anterior angles blunt and slightly protruded, posterior angles almost rectangular. Scutellar shield sparsely punctured, nearly heart-shaped, 1.6 times as wide as long. Each elytron with seven distinct striae, intervals sparsely punctured.

Prosternum (Fig. 2 g) finely and sparsely punctured, covered with fine and short setae, anterior edge narrow, posterior edge emarginated. Prosternal process nearly long bell-shaped, prosternal process distinctly and abruptly expanded apically, apical edge of prosternal process emarginated, only slightly extending beyond anterior edge of mesoventrite. Mesoventrite (Fig. 2 h) sparsely punctured, with a triangular depression in middle of posterior edge. Metaventrite finely and sparsely punctured and two elongated transverse depressions at posterior edge. Abdomen sparsely punctured, covered with short setae.

Legs (Fig. 2 i) with tibiae gradually widening to apices, tibiae and tarsus covered with golden setae.

Male genitalia (Fig. 2 j) with median lobe slightly curved, median strut straight, apex slightly wide, 2.3 times as long as median lobe.

Etymology

The species is named for the three indistinct teardrop-shaped orange marks on the pronotum, the marks seen when strong light shines on the pronotum.

Distribution

Micrencaustes (Mimencaustes) occulta Yang & Li sp. nov. is recorded in Yingjiang County, Yunnan Province, China.

Notes

Micrencaustes (Mimencaustes) occulta sp. nov. is similar to Micrencaustes (Micrencaustes) lunulata (Macleay, 1825) due to the body and colour. We examined type specimens of Micrencaustes (Micrencaustes) lunulata (Macleay, 1825) and laboratory collected specimens, these two species being distinguished by the combination of the following characters: Micrencaustes (Mimencaustes) occulta sp. nov. without postmesocoxal lines, each elytron with seven distinct striae, pronotum with a few coarse punctures on each side of the base, body moderately lustrous; Micrencaustes (Micrencaustes) lunulata (Macleay, 1825) with postmesocoxal lines, each elytron with eight distinct striae, pronotum with evenly fine punctures, body shiny.

Figures

Figure 1. Micrencaustes (Mimencaustes) occulta sp. nov., Yunnan, China.

Figure 2. Morphological characters of Micrencaustes (Mimencaustes) occulta sp. nov. a head; b antenna; c maxillary palpus; d labial palpus; e mentum and submentum; f pronotum; g prosternum; h mesoventrite; i protibia and protarsus; j aedeagus. Scale bars: 1.0 mm (a-b, e-j), 0.5 mm (c-d).