Euwallacea subalpinus, 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

Euwallacea subalpinus sp. nov. Fig. 58G, H, L

Type material.

Holotype, female, India: Assam-Arunachal Pradesh border [Assam]: Bhalukpong, 27°00'48"N, 92°39'08"E, 150 m, 1-8.v.2012, L. Dembický, ex FIT (ZFMK).

Diagnosis.

2.4 mm long (n = 1); 3.0 × as long as wide. This species is distinguished by its slender form; pronotum from dorsal view elongate, anterior margin rounded (type 7); outer margin of protibiae distinctly triangular, bearing five denticles, denticles not contiguous; and declivital strial punctures very large, coarse.

Similar species.

Euwallacea luctuosus , E. sibsagaricus .

Description

(female). 2.4 mm long (n = 1); 3.0 × as long as wide. Body ferruginous. Legs and antennae light brown. Head: epistoma entire, transverse, with a row of hair-like setae. Frons weakly convex to upper level of eyes; surface subshiny, alutaceous, punctate; punctures large, shallow, moderately spaced, setose; punctures bearing a long, erect hair-like seta. Eyes shallowly emarginate just above antennal insertion, upper part smaller than lower part. Antennal scape regularly thick, as long as club. Pedicel as wide as scape, shorter than funicle. Funicle 4-segmented, segment 1 shorter than pedicel. Club approximately circular, obliquely truncate, type 2; segment 1 corneous, transverse on anterior face, occupying basal 1/2, nearly covering posterior face; segment 2 narrow, corneous; segment 1 present on posterior face. Pronotum: 1.26 × as long as wide. In dorsal view long and rounded frontally, type 7, sides parallel in basal 3/4, rounded anteriorly; anterior margin without serrations. In lateral view elongate with disc much longer than anterior slope, type 7, disc flat, summit at apical 2/5. Anterior slope with densely spaced, low, broad asperities, becoming lower and more strongly transverse towards summit. Disc strongly shiny with sparse, minute punctures, some longer hair-like setae at margins. Lateral margins obliquely costate. Base transverse, posterior angles acutely rounded. Elytra: 1.68 × as long as wide, 1.34 × as long as pronotum. Scutellum moderately sized, linguiform, shiny, flush with elytra, flat. Elytral base transverse, edge oblique and unarmed by granules, humeral angles rounded, parallel-sided in basal 1/2, then broadly rounded to apex. Disc flat, shiny, striae not impressed, with large, shallow punctures separated by less than one diameter of a puncture, glabrous; interstriae flat, very sparsely finely punctate, punctures 1/3 size of strial punctures, each with a long, erect seta. Declivity occupying approximately 1/3 of elytra, rounded, declivital face convex, shiny and coarsely sculptured; striae not impressed, strial punctures very large and coarse, much larger and deeper than those of disc, setose, setae short, as long as strial punctures; interstriae impunctate, interstriae 1 and 3 with three and two large tubercles, respectively, as well as several granules, interstriae 2 sparsely granulate, tubercles and granules setose, setae long, erect. Posterolateral margin costate, granulate to interstriae 7. Legs: protibiae distinctly triangular, broadest at apical 1/4; posterior face smooth; apical 1/2 of outer margin with five large socketed denticles, their length much longer than basal width. Meso- and metatibiae flattened; outer margin evenly rounded with five and six large socketed denticles, respectively.

Etymology.

L. sub = under, below; alpinus = high mountains. In reference for the species occurrence in the foothills of the Himalayas. An adjective.

Distribution.

India (Assam).

Host plants.

Unknown.

Remarks.

The holotype is card mounted and ventral characters could not be examined.

Figures

Figure 58. Dorsal, lateral and declivital view of Euwallacea semirudis, 3.1 - 3.3 mm (A, B, I), E. sibsagaricus, 3.4 - 3.9 mm (C, D, J), E. similis, 2.3 - 2.5 mm (E, F, K), and E. subalpinus holotype, 2.4 mm (G, H, L).