Trachys scapuliformis Peng, 2022

Peng, Zhongliang, 2022, Studies on the Genus Trachys Fabricius from China (3) - A Faunal Survey of Hunan Province and Descriptions of Four New Species (Coleoptera: Buprestidae: Agrilinae: Tracheini), The Coleopterists Bulletin 76 (2), pp. 263-272 : 270-271

17. Trachys scapuliformis Peng , new species zoobank.org/ urn:lsid:zoobank.org:act:9BA2B773-E31E-46BE-885B-5A6B25D9B5C0 Figs. 12–14

Type Specimen. Holotype ( BPCQ), female, labeled: “Vil. Pipachong, 26°08′N, 109°48′E, altitude 450 m, suburb of Tongdao county town, Tongdao , Hunan, China, 1-X-2021, Leg. Z-L Peng et Y-Q Cai ”.

Description. Habitus ( Fig. 12 ): Length 3.6 mm, width 1.8 mm, surface uniformly dark brown-crimson with slight reflection, underside also dark brown-crimson but with brighter reflections centrally; a rather robust species. Head: Widely excavated between eyes; vertex rather narrow, slightly convex transversely, uniformly covered with indistinct scale-like or ocellate sculpture, irregularly clothed with brown-yellow pubescence mixed with sparse pale pubescence, frons deeply and widely depressed along midline, densely covered with recumbent pale-yellow pubescence; eyes reniform; antennal sockets situated just above lower margins of eyes, wide and deep; clypeus golden bronze, metallic and shiny; anterior margin transversely straight, clypeal suture arcuately emarginate, lateral sides narrowed at midlength; antenna short, barely reaching anterior margin of pronotum when laid alongside; antennal scape and pedicel both moniliform, 1.20 times as long as wide; antennomeres 3 – 6 cylindrical, much shorter than antennal scape and pedicel and slightly shorter than remaining apical ones, 1.50 times as long as wide; antennomeres 7 – 11 serrate; lateral sides of head arcuate from dorsal view, not on same bevel with lateral margins of pronotum. Pronotum: About 2.85 times as wide as long, widest at base, basal margin 1.61 times as wide as anterior margin in dorsal view, slightly narrower than elytra at base, but much narrower than at elytral humeri; lateral margins arcuately tapering from base to acute anterior angles; anterior margin slightly elevated, biarcuate with markedly produced median lobe; both basal inner and outer edges trisinuate, median lobe angulately produced posteriorly, extent of margin between outer and inner edges rather inequal, narrow or indistinct; disc slightly convex but slightly depressed along basal margin, surface uniformly covered with indistinct ocellate sculpture, densely and nearly uniformly clothed with brown-yellow pubescence irregularly mixed with white pubescent spots. Scutellar shield: Very small but clearly visible, triangular, smooth. Elytra: 1.43 times as long as wide, about 4.3 times as long as pronotum, widest at humeri and very strongly projecting at humeri; lateral margins slightly diverging from base to humeri, deeply emarginate from humeri to midlength, then arcuately converging to apices; apices jointly arcuate without distinct apical and lateral denticles; elytral surface convex; humerus strongly expanded as a bump; basal depressions rather wide; entire surface nearly evenly covered with brown-yellow pubescence except for markings of white pubescence consisting of three spots on basal half, and two zigzag transverse bands on apical half. Lateral View ( Fig. 13 ): Thickest point lying at basal third of elytra; maximal thickness strongly exceeding length of pronotum plus head; curvature with angle of 105° between pronotal margin and subhumeral lobe; basal part of elytral margin obliquely straight with very obtuse angle above metaventrite, humeral carina indistinct, with only an arcuate convex trace. Underside ( Fig. 14 ): Sparsely but nearly uniformly covered with short white pubescence; prosternal process about 1.43 times as long as wide, widest at apical angles; apical angles weakly acute, lateral margins diverging from base to apical angles; basal half clavate, and apical half fan-shaped; apical margin arcuate; surface smooth, sparsely clothed with white pubescence; anterior part of prosternum butterfly-shaped; anterior margin broadly but slightly emarginate in middle, posterior margin arcuately oblique on each side; hypomeron with a sub-semilunar depressed marking near inner side, outside quite smooth; metaventrite with sparse ocellate sculpture centrally but covered with strong oblique or arcuate wrinkles near sides and along anterior margin, anterior margin deeply and arcuately emarginate; first abdominal ventrite covered with dense longitudinal and reticulate wrinkles, remaining ventrites nearly uniformly with biarcuate or triarcuate sculpture; posterior margin of anal ventrite arcuately acuminate. Legs: Procoxa and mesocoxa globular, metacoxa expanded as a transverse plate and covered with ocellate sculpture; all trochanters small, nearly triangular; all femora moderately dilated; all tibiae slender with pale pubescence, row of brown-yellow, soft spines along outer and inner sides; all tarsi light yellow; each claw with a swollen tooth at base. SeXual dimorphism: Male unknown.

Differential Diagnosis. This species is rather peculiar and only slightly resembles Trachys scapulis Peng, 2021 , but can be distinguished by the shape of prosternal process which is widely dilated and fan-shaped in T. scapuliformis , but that in T. scapulis has subparallel lateral sides; the lateral sides of the pronotum are generally arcuate in T. scapuliformis , while in T. scapulis the lateral sides are rather oblique.

Etymology. The species name consists of two words, the species name “scapulis ” and the Latin adjective “forma”, meaning “form”, referring to the new species’ similarity to T. scapulis .

Figures

Figs. 11–14. 11) Trachys latiquadratus, new species, aedeagus (fully dissected). 12–14) T. scapuliformis, new species, holotype, female: 12) Dorsal view; 13) Lateral view; 14) Ventral view.