Trachys parviformis Peng, 2023

Peng (彭忠亮), Zhongliang, 2023, Studies on the Genus Trachys Fabricius from China (4) - A Faunal Survey of Jiangxi Province and Descriptions of Two New Species (Coleoptera: Buprestidae: Agrilinae: Tracheini), The Coleopterists Bulletin 77 (2), pp. 239-247 : 244-245

17. Trachys parviformis Peng , new species zoobank.org/ urn:lsid:zoobank.org:act:FFCD06BD-EC53-409F-9797-B60E744722FD Figs. 7–10

Type Specimens. Holotype ( BPCQ), female, labeled: “Tianpaishan, 24°51′N 114°31′E, altitude 880 m, Longnan, Jiangxi, China, 19-IX-2021, Leg. Z-L Peng et X-Q Sheng, 江&省Ê南县Rü山 ”; paratype ( ZLPN), female, labeled: “ Huangshikeng , 25°30′N 114°18′E, altitude 370 m, Shiluocun , Qianchangzhen , Chongyi , Jiangxi, China, Leg. Z-L Peng et X-Q Sheng, 江&省崇义县ffl厂ä 石¶村¢石ṻ ”.

Description. Habitus ( Fig. 8 ): Length 2.5 mm, width 1.7 mm; surface uniformly brown crimson with slightly bronze reflections, underside a brownbronze with slightly crimson tinges, a very small but rather robust and ovate species. Head ( Fig. 10 ): Widely excavated between eyes; vertex transversely and arcuately flattened, uniformly covered with distinct scale-like or ocellate sculpture, and uniformly clothed with pale pubescence; frons depressed along midline with a very deep longitudinal groove, nearly uniformly covered with pale pubescence and simple punctures; eyes reniform, inner margins slightly carinate and oblique; antennal sockets situated just above lower margins of eyes, round and open near sides; two frontal holes rather round, just situated above clypeus each side; clypeus golden green, metallic and shiny, nearly rectangular, about 1.6 times as wide as long, anterior margin with a semilunar notch, clypeal suture slightly emarginate, lateral sides narrowed at midlength; antennae rather short, barely reaching anterior margin of pronotum when laid alongside; antennal scape clavate, about 2 times as long as wide, pedicel moniliform, 1.50 times as long as wide; antennomeres 3 – 6 cylindrical, much shorter than antennal scape and pedicel and slightly shorter than remaining apical ones, 1.80 times as long as wide; antennomeres 7 – 11 serrate; lateral sides of head oblique from dorsal view, narrower at base than anterior margin of pronotum. Pronotum: 3.0 times as wide as long, widest at base, basal margin 1.62 times as wide as anterior margin in dorsal view, much narrower than elytra at base and at humeri; lateral margins slightly arcuately converging from base to acute anterior angles; anterior margin biarcuate with median lobe slightly produced forwards; both inner and outer basal edges trisinuate, median lobe of inner basal edge angulate medially, but that of outer basal edge arcuate, extent of margin between outer and inner edges narrow but rather distinct and transversely equal; disc convex medially, but slightly depressed along basal margin, surface uniformly covered with scaly or ocellate sculpture, nearly uniformly clothed with pale setae mixed with very sparse brown-yellow ones, slightly glabrous centrally. Scutellar shield: Very small but clearly visible, triangular, smooth. Elytra: 1.30 times as long as wide, 4.4 times as long as pronotum, widest at humeri; lateral margins from base to humeri arcuate, from humeri emarginate to midlength, then converging to apices, apices jointly arcuate with sparse apical and lateral denticles; elytral surface slightly convex; humeri strongly projecting beyond elytral outline; basal depressions rather wide; entire surface nearly uniformly covered with foveae but such ones near suture larger, nearly evenly clothed with pale pubescence mixed with a few pale-yellow ones; ornamentation consisting of dense pale pubescence on each elytron including three indistinct oblique stripes on basal half and two indistinct zigzag bands on apical half. Lateral View ( Fig. 7 ): Thickest point lying at basal third of elytra; maximal thickness greatly exceeding length of pronotum plus head; curvature with angle of 130° between pronotal margin and subhumeral lobe; basal part of elytral margin obliquely straight with obtuse angle above metaventrite, humeral carina indistinct, with only an arcuate convex trace. Underside ( Fig. 9 ): Irregularly covered with short pale pubescence, but denser on abdomen; prosternal process about 1.2 times as long as wide, widest at apical angles; apical angles angulate, lateral margins slightly arcuately emarginate in basal half, from midlength widely diverging to apical angles, apical margin arcuate, entire apical half dilated and fan-shaped; anterior part of prosternum butterfly-shaped, narrow, anterior margin slightly trisinuate, posterior margin oblique on each side, lateral margins slightly oblique; hypomeron with an ear-shaped depressed marking near inner side; metaventrite rather smooth centrally with indistinct foveae, near sides and anterior margin covered with strong arcuate wrinkles and reticulate sculpture; anterior margin deeply emarginate; first abdominal ventrite covered with dense longitudinal ocellate sculpture, remaining ventrites with smooth reticulate sculpture, both posterior margins of anal ventrite and pygidium acuminate medially. Legs: Procoxa and mesocoxa globular, posterior coxa expanded as a transverse plate and covered with ocellate sculpture and dense pale pubescence; all trochanters small, nearly triangular; all femora moderately dilated; all tibiae slender and slightly arcuate with pale pubescence; all tarsi light yellow; each claw with a swollen tooth at base. Sexual dimorphism: Male unknown.

Differential Diagnosis. This species resembles Trachys chalingensis Peng, 2022 , but it can be distinguished by its fan-shaped prosternal process and more projected humeri.

Etymology. The species name consists of two Latin words, “parvus” meaning “small” and “forma” meaning “form”, referring to rather small size of the species.

Figures

Figs. 2–10. New species of Trachys, holotypes. T. jinpenshanensis, new species, male: 2) Dorsal view; 3) Lateral view; 4) Ventral view; 5) Head-frontal view; 6) Aedeagus. T. parviformis, new species, female: 7) Lateral view; 8) Dorsal view; 9) Ventral view; 10) Head-frontal view.