Horniolus hainanensis Chen & Ren

Chen, Xiaosheng, Xie, Xiufeng, Ren, Shunxiang & Wang, Xingmin, 2016, A taxonomic review of the genus Horniolus Weise from China, with description of a new species (Coleoptera, Coccinellidae), ZooKeys 623, pp. 1-19 : 5-8

Taxon classification Animalia Coleoptera Coccinellidae

Horniolus hainanensis Chen & Ren sp. n. Figs 3, 7

Diagnosis.

This species is similar to Horniolus amamensis Miyatake and Horniolus kyushuensis Miyatake in general appearance, but can be separated from the latter by having incomplete abdominal postcoxal lines (Fig. 3d) and broader body outline (Fig. 3a). The stout penis guide (Fig. 3 g–h) and the peculiar apex of penis (Fig. 3f) are also diagnostic.

Description.

TL: 2.50-3.20 mm, TW: 1.80-2.41 mm, TH: 1.22-1.53 mm, TL/TW: 1.32-1.39, PL/PW: 0.51-0.53, EL/EW: 1.01-1.02, HW/PW: 0.60-0.62, PW/EW: 0.76-0.78.

Body rounded, moderately convex, dorsum covered with white pubescence (Fig. 3 a–c). Head black (Fig. 3b). Antennae and mouthparts dark brown. Pronotum and scutellum black. Elytra black with four yellowish spots, first pair transverse, almost straight, parallel to elytral base, situated at anterior ⅓ length of elytra; second pair comma-shaped, located in apical ⅓ length, not reaching suture and lateral margins (Figs 3a, 3c). Prothoracic hypomeron and prosternum black. Mesoventrite and metaventrite black. Elytral epipleuron dark brown with inner and outer margins black. Legs black except tarsi brown.

Head with coarse frontal punctures, distinctly larger than eye facets, 0.5 diameter apart. Eyes finely faceted, interocular distance 0.53 times head width. Pronotal punctures smaller than those on frons, 1.0-2.0 diameters apart. Surface of elytra with punctures larger than those on pronotum, separated by 1.0-2.0 diameters. Prosternal carinae Y-shaped with stem ⅓ as long as arm, arms broadly separated. Abdominal postcoxal lines strongly recurved and distinctly incomplete laterally (Fig. 3d), reaching 4/5 length of abdominal ventrite 1, area enclosed by lines coarsely punctate, narrowly smooth along line. Abdominal ventrite five weakly emarginated apically in male.

Male genitalia. Penis stout, evenly curved (Fig. 3e); penis capsule with long inner arm and short outer arm; apex of penis slightly expanded (Fig. 3f). Tegmen stout (Figs 3 g–h) with penis guide parallel-sided from base to ¾ length, then tapering gradually to blunt apex in ventral view (Fig. 3g). Parameres tapering toward apex, shorter than penis guide, densely covered with long setae at apices (Fig. 3h).

Female externally similar to male but with abdominal ventrite 5 truncate apically.

Type material.

Holotype: male, No. 20070320057, CHINA: Hainan: Tongza, 18°54.22'N, 109°40.49'E, ca 470 m, VIII. 1995, Peng ZQ leg (SCAU). Paratypes (10): Hainan: 1♀ with same data as holotype. 1♂, Wuzhishan National Nature Reserve, 18°47.07'N, 109°31.98'E, ca 650 m, 22. XI. 1991, Peng ZQ leg. 2♀, Wuzhishan National Nature Reserve, 18°47.07'N, 109°31.98'E, ca 650 m, 8. VI. 1994, Tian MY leg. 1♂, Wuzhishan, 18°47.0'N, 109°31.98'E, ca 650 m, VIII.1995, Peng ZQ leg. 1♂1♀, Lianyuan, Nada, Danzhou City, 19°30.77'N, 109°29.77'E, VIII. 1995, Peng ZQ leg. 1♂, Maoyang Town, Qiongzhong County, 18°56.18'N, 109°30.31'E, ca 230 m, IX.1995, Peng ZQ leg. 1♂, Bawangling National Nature Reserve, 19°05.49'N, 109°06.38'E, ca 260 m, 3. IX. 1998, Peng ZQ leg. 1♂, Limushan National Forest Park, 19°14.05'N, 109°48.03'E, ca 160 m, 22.VII.2006, Dong XL leg (SCAU).

Distribution.

China (Hainan).

Etymology. The specific epithet refers to its type locality, Hainan Island.