Xyleborinus ephialtodes, Smith & Beaver & Cognato, 2020

Smith, Sarah M., Beaver, Roger A. & Cognato, Anthony I., 2020, A monograph of the Xyleborini (Coleoptera, Curculionidae, Scolytinae) of the Indochinese Peninsula (except Malaysia) and China, ZooKeys 983, pp. 1-442 : 1

Xyleborinus ephialtodes sp. nov. Fig. 83E, F, K

Type material.

Holotype, female, China: Fujian, Zhangzhou, 14.xii.2017, Shouping Cai, Haitian Song, ex Schima superba (IZAS).

Diagnosis.

2.6 mm long (n = 1); 2.6 × as long as wide. This species is distinguished by the discal interstriae confused; posterior margin of elytra broadly rounded; declivital face with interstriae 1 and 2 granulate, unarmed by tubercles; declivital face weakly sulcate; large body size; lateral declivital margins elevated, bearing five pairs of moderate, narrow, sharply pointed spines of equal size; sulcate area of declivity shagreened, dull; and stout body.

Similar species.

Xyleborinus artestriatus , X. echinopterus , X. octiesdentatus , X. schaufussi , X. speciosus , X. spinipennis .

Description

(female). 2.6 mm long (n = 1); 2.6 × as long as wide. Body dark red-brown. Legs and antennae light brown. Head: epistoma entire, transverse, with a row of hair-like setae. Frons weakly convex to upper level of eyes, alutaceous, subshiny, finely, densely punctate, setose; punctures bearing a long, erect hair-like seta. Eyes shallowly emarginate just above antennal insertion, upper part smaller than lower part. Submentum large, distinctly triangular, deeply impressed. Antennal scape regularly thick, as long as club. Pedicel as wide as scape, as long as funicle. Funicle 4-segmented, segment 1 shorter than pedicel. Club wider than long, obliquely truncate, type 1; segment 1 corneous, encircling anterior face; segment 2 narrow, concave, corneous on anterior face only; sutures absent on posterior face. Pronotum: 0.9 × as long as wide. Basic and parallel-sided, type 2 in dorsal view, sides parallel in basal 2/3, rounded anteriorly; anterior margin without serrations. In lateral view type 7, elongate, disc longer than anterior slope, summit low, on apical 2/5. Anterior slope with densely spaced narrow asperities, becoming lower and more strongly transverse towards summit, bearing long, fine, semi-recumbent hair-like setae. Disc subshiny, alutaceous, finely punctate, finely setose, setae short, erect hair-like, some longer hair-like setae at margins. Lateral margins obliquely costate. Base transverse, posterior angles acutely rounded. Elytra: 1.62 × as long as wide, 1.78 × as long as pronotum. Scutellum minute, conical, disconnected from elytra, surrounded by dense mycangial tuft of setae. Elytral base transverse, medially emarginate near scutellum and mycangial tuft, edge oblique, humeral angles angulate, parallel-sided in basal 3/4, then broadly rounded to apex. Disc occupying basal 3/5, smooth, shiny, glabrous, unarmed; striae not impressed, glabrous, with small punctures separated by two diameters of a puncture; interstriae flat, sparsely finely punctate, punctures confused, 1/2 those of striae, glabrous. Declivital face shagreened, dull, steeply rounded, weakly sulcate between interstriae 3, striae and interstriae densely setose, setae long, erect hair-like, as long as the distance between suture and interstriae 3; three striae present; strial punctures as larger, deeper than on disc; interstriae 1 and 2 flat, granulate along their length; interstriae 2 very narrow; interstriae 3 forming declivital margin, distinctly elevated, bearing five pairs of moderate, narrow, sharply pointed spines of equal size. Posterolateral margin without a costa, spinose and denticulate from interstriae 3-7, apical pair largest. Legs: procoxae contiguous; prosternal coxal piece tall, pointed. Protibiae obliquely triangular, broadest at apical 1/3; posterior face smooth; apical 1/3 of outer margin with seven moderate socketed denticles, their length approximately as long as basal width. Meso- and metatibiae flattened; outer margin evenly rounded with ten and eight moderate socketed denticles, respectively.

Etymology.

G. ephialtes = nightmare; - odes = resembling. In reference to the nightmarish long, acute spines on the declivity. A noun in apposition.

Distribution.

China (Fujian).

Host plants.

This species is only known from Schima ( Theaceae ).

Figures

Figure 83. Dorsal, lateral and declivital view of Xyleborinus disgregus holotype, 1.8 - 2.0 mm (A, B, I), X. echinopterus holotype, 3.0 mm (C, D, J), X. ephialtodes holotype, 2.6 mm (E, F, K), and X. exiguus, 1.8 - 2.0 mm (G, H, L).