Anthaxia (Merocratus) zhengyucheni Qi & Song, 2025

Anthaxia (Merocratus) zhengyucheni Qi & Song , sp. n.

(Chinese common name: 郑氏花纹吉丁)

( Figures 1 View Figure 1 , 5 View Figure 5 (a–d), 6(a–d), 7(a, b), 8(a, b), 9(a–c))

Type material

Holotype: ♂ ( FAF), CHINA: Hainan Island, Qiongzhong County, Limushan Town [黎母山 镇], Limu Mountain [黎母山], Limu Temple [黎母庙], 19°8 ʹ 54.4”N, 109°45 ʹ 49.8”E, alt. 600 m, 23.IV.2022, Yu-Chen Zheng leg. GoogleMaps Allotype: ♀ ( FAF), CHINA: Hainan Island, Changjiang County, Bawangling [霸王岭], Yajia Waterfall [雅加瀑布], 19°5 ʹ 5”N, 109° 7 ʹ 35.5”E, alt. 500 m, 3.V.2022, Yu-Chen Zheng leg. GoogleMaps

Description

Holotype. ♂ specimen ( Figure 1 View Figure 1 (a, c)). Length 5.18 mm, width 1.89 mm, length/width ratio: 2.74; aedeagus length: 1.52 mm, width: 0.27 mm, length/width ratio: 5.63.

Habitus ( Figure 1 View Figure 1 (a,c)). slender, convex and lustrous, acuminate posteriorly; frons ( Figure 5 View Figure 5 (a)) metallic green, vertex ( Figure 6 View Figure 6 (a)) black; antennae ( Figure 5 View Figure 5 (c)) metallic green to metallic blue; pronotum ( Figure 6 View Figure 6 (a)) metallic green with two large, black, more or less triangular spots narrowed posteriorly; scutellum ( Figure 6 View Figure 6 (a)) metallic green; elytra ( Figure 1 View Figure 1 (a)) black to dark violet, the anterior margin of elytra and both sides of anterior third of elytral suture form an approximately triangular metallic green area, two large metallic green semicircular maculae along lateral margins, lateral margins with very narrow metallic green stripes extending to the apex, terminal quarter of elytra with two broad longitudinal metallic green stripes along the suture; front leg metallic green, middle and hind legs almost black with a hint of metallic green in dorsal view. Most of the ventral surface ( Figure 1 View Figure 1 (c)) metallic green, 2–5 ventrite nearly black with a small part of metallic green at the apex of anal ventrite ( Figure 8 View Figure 8 (a)).

Head ( Figures 5 View Figure 5 (a, c), 6(a)). relatively large, partly retracted into prothorax, narrower than anterior pronotal margin; frons ( Figure 5 View Figure 5 (a)) deeply depressed, vertex ( Figure 6 View Figure 6 (a)) depressed, about 0.4 times as wide as width of eye; eyes large, reniform, weakly projecting beyond outline of head, inner margins S-shaped, strongly converging towards vertex and slightly converging towards frons ( Figure 5 View Figure 5 (a)); sculpture of frons consisting of large, rounded and polygonal cells with small central punctures, vertex with smaller, polygonal ocellation; antennae ( Figure 5 View Figure 5 (c)) longer than the length of pronotum, reaching midlength of pronotum when laid alongside; scape long, claviform, 3.0 times as long as wide, pedicel suboval about 1.5 times as long as wide, third antennomere claviform, 2.4 times as long as wide, fourth antennomere suboval, 1.6 times as long as wide, antennomeres 5–10 trapezoidal, 1.1–1.2 times as long as wide, terminal antennomere rhomboid, 1.9 times as long as wide.

Pronotum ( Figure 6 View Figure 6 (a)). strongly convex, 1.5 times as wide as long, widest near midlength, with wide and shallow lateroposterior depressions; anterior margin widely and shallowly emarginate, front angles protruding to the front slightly; lateral margins angulately rounded; posterior margin bold almost straight, with very dense denticulation, posterior angles obtused. Anterior portion in the middle of pronotum consisting of rounded reticulate cells sculpture without central grains; anterior areas in the lateral sides of pronotum with fine, longitudinal and extruded condition rugae; prescutellar portion with larger, strongly transverse sculpture; lateroposterior portions with large, rounded reticulate cells sculpture without central grains.

Scutellum ( Figure 6 View Figure 6 (a)). small, flat, pentagonal and microsculptured, about 1.2 times as wide as long.

Elytra ( Figure 1 View Figure 1 (a)). convex, widest behind the base, tapering regularly from humeri to apex, 2.0 times as long as wide; basal, transverse depressions obviously not reaching scutellum; humeral callosities small, not projecting beyond elytral outline; elytral apices rounded, with very fine serrations; elytral sculpture almost homogeneous, consisting of fine, dense, simple punctures.

Legs ( Figures 1 View Figure 1 (a, c), 6(b)). relatively long and slender. Protibiae weakly bent inwards, inner margin with a row of setae; mesotibiae and metatibiae ( Figure 6 View Figure 6 (b)) straight, inner margins with several shallow, preapical, and very fine serrations; outer angles of metacoxae projecting and sharp; tarsomeres 1–4 with adhesive pads; tarsal claws thin, hook-shaped.

Ventral side ( Figures 1 View Figure 1 (c), 7(a), 8(a)). lustrous with widely ocellate sculpture and white setae; prosternal process ( Figure 7 View Figure 7 (a)) widely expanded behind procoxae and sharply pointed apically (apex angle), with two lateral angles at base of apex angle, the inside angle of two lateral angles greater than the apex angle. Anal ventrite ( Figure 8 View Figure 8 (a)) weakly truncate apically, with very fine serrations and a very small notch at the tip.

Aedeagus ( Figure 9 View Figure 9 (a, b)). long, slender, weakly spindle-shaped; apices of parameres sharp and translucent, apical portion of each paramere lateral expand with serrated lateral margin, base of the extension part with a longitudinal translucent stripe and the stripe completely surrounded by the black chitinous part; median lobe sharply pointed apically, without visible lateral serrations.

Allotype: Variation ( Figure 1 View Figure 1 (b, d)). length 5.98 mm, width 2.11 mm, length/width ratio: 2.83. Vertex ( Figure 6 View Figure 6 (c)), 0.4 times as wide as width of eye; antennae ( Figure 5 View Figure 5 (d)), shorter, equal to the length of pronotum, reaching mid-length of pronotum when laid alongside; scape long, claviform, 2.7 times as long as wide, pedicel suboval about 1.2 times as long as wide, antennomeres 3–10 trapezoidal, 0.7–1.3 times as long as wide, terminal antennomere rounded, as long as wide. Inner margins of eyes not S-shaped, strongly converging towards vertex, but straight along the frons. Pronotum ( Figure 6 View Figure 6 (c)), 1.6 times as wide as long; scutellum ( Figure 6 View Figure 6 (c)), about 1.3 times as wide as long; elytra ( Figure 1 View Figure 1 (b)), 2.0 times as long as wide. Elytra overall wider than male, the bright part of elytra metallic green to metallic yellow. Inner margin of mesotibiae with several shallow, preapical and very fine serrations; inner margin of metatibiae ( Figure 6 View Figure 6 (d)) without serrations. Anal ventrite ( Figure 8 View Figure 8 (b)) with a small rounded notch at the tip. For the character of ovipositor, see Figure 9 View Figure 9 (c). Apart from the differences described above, the female adult is similar to the male in other external characters, without obvious sexual dimorphism.

Differential diagnosis

The new species is most similar to A. (M.) tamdaoensis Bílý, 1998 ( Figure 3 View Figure 3 ), but by a combination of external and genital characters (vide key), it can be clearly distinguished from the related species: (1) pronotum with two large black spots, rather than with two smaller black ones in A. (M.) barbieri Descarpentries, 1958; (2) elytra black to dark violet with a pair of large metallic green semicircular maculae along lateral margins, rather than green-bronze without maculae along lateral margins in A. (M.) angustata Bílý, 2019; (3) anal ventrite weakly truncate apically, with a very small notch at the tip, rather than anal ventrite truncate apically, without a notch at the tip in A. (M.) barbieri; and (4) the portion near apical lateral expand part of paramere slightly narrowed, lateral expand portion with serrated outer margin, rather than the portion near apical lateral expand part of paramere distinctly narrowed in A. (M.) barbieri or the lateral expand portion without serrated outer margin in A. (M.) angustata.

Etymology

This species is named after Mr. Yu-Chen Zheng ( China Agricultural University , Beijing, China), who collected and provided the type specimens for our study.

Distribution

China (Hainan).

Biology

Adults were collected on the flowers of Maclurodendron oligophlebium ( Rutaceae ) ( Figure 10 View Figure 10 ) and a certain of Fagaceae trees, during daytime from April to May.

Remarks

This species belongs to the A. (M.) insulaecola species-group. Currently, the adult variation of this species is unclear due to the limited number of specimens. Rutaceae is reported as host plant in family level of Merocratus adult for the first time.