Cyclorhipidion denticauda, 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

Cyclorhipidion denticauda sp. nov. Fig. 41C, D, J

Type material.

Holotype, female, Vietnam: Cao Bang, 22°34.5'N, 105°52.4'E, ~1080 m, 14.iv.2014, VN20, Cognato, Smith, Pham, ex branches (MSUC). Paratype, female, China: Jiangxi, Jinggang Shan Mts., Xiangzhou vill. env., 26°35.5'N, 114°16.0'E, 374 m, (rice fields, forested stream valley), 26.iv.2011, M. Fikáček & J. Hájek (RABC).

Diagnosis.

2.95-3.1 mm long (mean = 3.02 mm; n = 2); 2.81-3.1 × as long as wide. This species is distinguished by the declivital slope gentle, gradual; separation between the smooth, shiny elytral disc and shagreened declivity gradual, not sharply distinct; declivital striae weakly impressed, punctures large, distinct; declivital interstriae tuberculate with three large equally spaced tubercles along interstriae 1 and 3, those of interstriae 3 smaller; interstriae 2 granulate near base, interstriae 4 granulate along its length; and elytral apex and posterolateral margin armed with alternating spines and denticles, a single spine on each interstriae and a smaller denticle on each striae from suture to interstriae 7.

Similar species.

Cyclorhipidion ohnoi , C. petrosum , C. pilipenne .

Description

(female). 2.95-3.1 mm long (mean = 3.02 mm; n = 2); 2.81-3.1 × as long as wide. Body red. 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, impunctate, alutaceous, rugose. Eyes shallowly emarginate just above antennal insertion, upper part smaller than lower part. Submentum narrow, triangular, shallowly impressed. Antennal scape regularly thick, as long as club. Pedicel as wide as scape, shorter than funicle. Funicle 4-segmented, segment 1 as long as pedicel. Club approximately circular and flat, type 3; segment 1 corneous, transverse on anterior face, occupying approximately basal 2/5; segment 2 narrow, corneous; segments 1 and 2 present on posterior face. Pronotum: 1.24 × 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 shagreened, with densely spaced, fine, narrow asperities, becoming lower and more strongly transverse towards summit, bearing long, fine, semi-recumbent, hair-like setae. Disc subshiny, alutaceous, densely, finely punctate, finely setose, setae short, erect, hair-like. Lateral margins obliquely costate. Base transverse, posterior angles broadly rounded. Elytra: 1.92 × as long as wide, 1.54 × as long as pronotum. Scutellum large, broad, linguiform, flush with elytra, flat, shiny. Elytral base transverse, edge oblique, humeral angles rounded, parallel-sided in basal 4/5, then broadly rounded to apex. Disc flat, strongly shiny, striae setose, setae short, semi-recumbent, hair-like, interstriae glabrous, striae not impressed, punctures uniseriate, spaced by two or three diameters of a puncture, interstriae minutely punctate, punctures 1/2 size of strial punctures, strongly confused, separated by five diameters of a puncture. Declivity occupying 2/5 of elytra, declivital slope gradual, rounded, strongly shagreened, separation between the smooth, shiny disc and shagreened declivity gradual, not sharply distinct; six striae present, striae 2 equidistant between 1 and 3, striae weakly impressed, punctures large, shallow, distinct, subcontiguous to spaced one diameter of a puncture, shagreened, much larger than on disc, glabrous; interstriae feebly convex, interstriae setose, setae dense, very long, erect hair-like; interstriae 1 laterally broadened from declivital summit to apical 1/3 then narrowed to apex, interstriae impunctate, tuberculate with three large equally spaced tubercles along interstriae 1 and three smaller tubercles on interstriae 3, interstriae 4 granulate, interstriae 2 denticulate near summit. Apex and posterolateral margin armed with alternating spines and denticles, a single spine on each interstria and a smaller denticle on each stria from suture to interstriae 7. Legs: procoxae contiguous; prosternal coxal piece tall, conical. Protibiae semi-circular with evenly rounded outer edge, 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 broad, flattened; outer margin evenly rounded with ten and 12 moderate socketed denticles, respectively.

Etymology.

L. dentis = tooth; cauda = tail. In reference to the declivity which is adorned with spines and denticles. Noun in apposition.

Distribution.

China (Jiangxi), Vietnam.

Host plants.

Unknown.

Figures

Figure 41. Dorsal, lateral and declivital view of Cyclorhipidion circumcisum, 3.3 - 3.5 mm (A, B, I), C. denticauda holotype, 2.95 - 3.1 mm (C, D, J), C. distinguendum, 2.5 - 3.1 mm (E, F, K), and C. fouqueti lectotype, 1.8 mm (G, H, L).