Eustra yinggelingensis Jiang, 2019

Jiang, Ri-Xin, Wang, Cheng-Bin, Mi, Hong-Xu & Wang, Shuo, 2019, Eustra yinggelingensis sp. nov., a new flanged bombardier beetle from Yinggeling Nature Reserve, Hainan, China with contribution to the knowledge of Chinese Eustra species (Coleoptera, Carabidae, Paussinae), Zootaxa 4668 (2), pp. 271-276 : 273-275

Eustra yinggelingensis Jiang R-X, Wang C-B & Wang S, sp. n. ṞDflffiffläę

Figs 1 , 2

Type material (6 specimens). Holotype: CHINA: ³, labelled ‘ China: Hainan, Baisha County (ŭṅẓ), Nankai Township (Ṓ=¼), near Budao Village (ƾựffi), 19°03′00″N, 109°23′21″E, H: 284~ 364m, 19.IV.2018, in rotten wood, Jiang Ri-Xin leg.’ ( SHNU) . Paratypes: CHINA: 5 ³³, same label data as the holotype (1 ³, MYNU; 1 ³, IZAS; 1 ³, SCAU; 2 ³³, SHNU) .

Comparative diagnosis. Eustra yinggelingensis sp. n. highly resembles the Vietnamese species E. csikii Jedlička, 1968 ; the two species share similar habitus characters, such as large dark spots on elytra. However, the two species can be well distinguished by the different form of aedeagus, and E. yinggelingensis possesses a much longer glabrous area along the outside of elytral spot than E. csikii .

Description. Male. Body ( Fig 1A ) 3.09–3.25 mm long. Head and pronotum reddish-brown; each elytron reddish-brown in basal 1/3, dark-brown in apical 2/3, and with a large obscurely dark spot at near side.

Head ( Fig. 1B ) about as long as wide, convex and gently covered with short setae, surface with faint and irregular microsculpture; fully carinate near eyes. Clypeus gently concave anteriorly, with 2 pairs of long setae at anterior margin. Labrum minutely denticulate and 4 pairs of long setae at anterior margin. Eyes medium sized, hemispherical. Antennae ( Fig. 2C ) nearly moniliform, antennomere I expanded, II–IV clavate, gradually increasing in diameter distally; V–IX almost as long as wide; XI the longest, as long as VIII–X combined.

Pronotum ( Fig. 1C ) sparsely covered with yellow setae; wider than long, widest at apical third; moderately narrowing anteriorly and posteriorly, more posteriorly than anteriorly; lateral margins with small, weak and blunt teeth; front angles strongly produced; midline distinct, almost reaching both anterior and posterior borders.

Elytra ( Fig. 2A ) densely punctuate and pubescent, distinctly wider than prothorax; shoulders rounded; surface moderately covered with short setae and with faint and irregular microsculpture, but with glabrous area along the out side of dark spot and about 2/3 length as elytra. Hind wings well developed.

Legs ( Fig. 1A ) simple and slender, covered with short hairs and denser at apical tibial apices. Both terminal spurs of pro-tibiae ( Fig. 2B ), almost equal in length.

Sternite VII ( Fig. 2G ) wide and truncate, slightly acute at middle, with 4 long setae near apical margin, the inner two longer than the two others. Median lobe of aedeagus as in Fig. 2D , ending in a blunt tip, with a spoon-shaped sclerite on endophallus; right paramere ( Fig. 2E ) arcuate, weakly expanded and rounded at apex, with long hair along apical margin; left paramere as in Fig. 3F , large, glabrous, and widely rounded at apex.

Female. Unknown.

Measurements. BL 3.09–3.25 mm; HL 0.71–0.76 mm, HW 0.70–0.73 mm; PL 0.53–0.55 mm, PW 0.78–0.82 mm; EL 1.85–1.94 mm, EW 1.31–1.37 mm; AnL 1.54–1.57 mm; MlL 0.71mm.

Distribution. China: Hainan.

Biological notes. All adults were collected in rotten wood; no association with ants detected ( Fig. 3 ).

Etymology. The new species is named after its type locality: the Yinggeling Nature Reserve. The local geographic name “Yinggeling” means “a Mountain with many Parrots”.

Notes on the type locality. Yinggeling Nature Reserve is located in the south centre of Hainan Island (109°11′27″– 109°34′06″E, 18°49′30″– 19°08′41″N), which is ~50464 hm 2 in total area and from 170 m to 1812 m in altitude. This nature reserve is the largest natural tropical rainforest in South China. With many effective protection means, the nature reserve maintained the original ecological environment; 96.03% of its surface is covered with forest .

Figures

FIGURE 1. A. Dorsal habitus of Eustra yinggelingensis sp. n.; B. Head, ventral view; C. Pronotum, dorsal view. Scale bars: 0.5 mm (Fig. 1A); 0.2 mm (Fig. 1B–C).

FIGURE 2. Diagnostic features of Eustra yinggelingensis sp. n. A. Right elytra, dorsal view; B. Foreleg; C. Antenna; D. Aedeagus, right lateral view; E. Right paramere, right lateral view; F. Left paramere, left lateral view; G. Male sternite VII, dorsal view. Scale bars: 0.5 mm (Fig. 2A); 0.2 mm (Fig. 2B–D, G); 0.1 mm (Fig. 2E–F).

FIGURE 3. Habitat of Eustra yinggelingensis sp. n. A. General environment of Yinggeling Nature Reserve; B. Microenvironment of the type locality (in rotten wood in the forest).