Myrmecina shanyii Gu & Chen, 2025

Gu, Zhuojian, Zhang, Chen, Du, Congcong & Chen, Zhilin, 2025, Synopsis of the ant genus Myrmecina Curtis, 1829 from China (Hymenoptera, Formicidae, Myrmicinae), with description of eleven new species, Deutsche Entomologische Zeitschrift 72 (2), pp. 395-448 : 395-448

Myrmecina shanyii Gu & Chen sp. nov.

Fig. 49

Material examined.

Holotype. • worker, Jianfengling , Hainan, China, 18.7482°N, 108.8463°E, 895 m, secondary forest, leaf litter, 15. VII. 2023, Xiaoyun Liang, GXNU 230741 [ GXNU] . Paratypes. • 6 workers, with the same collection data as the holotype ; • 4 workers, Jianfengling , Hainan, China, 18.7423°N, 108.8491°E, 926 m, secondary forest, leaf litter, 19. VI. 2024, Benan Zhang, GXNU 240512 [ 8 workers, GXNU; 1 worker, IZCAS] .

Diagnostic features.

(1) Head rectangular ( CI 101–104), lateral margins rounded and posterolateral corners convex; (2) mandibles with 6–7 teeth, including a basal denticle; (3) anterior margin of clypeus nearly straight, lacking median denticle but bearing distinct anterolateral projections; (4) eumetanotal spines projecting above mesosomal outline; (5) propodeal spines with length equal to their basal width and upturned apices; (6) distinctly compressed postpetiole (height> length) with straight dorsal margin; (7) oblique posterolateral rugae on frons combined with punctate-rugulose lateroventral head sculpture.

Notes.

M. shanyii Gu & Chen , sp. nov. is closely resembles M. shixui Gu & Chen , sp. nov. in sharing rugose antennal scapes, M. shanyii Gu & Chen , sp. nov. differs markedly from M. shixui Gu & Chen , sp. nov. through the following diagnostic traits: (1) the head of M. shanyii Gu & Chen , sp. nov. is rectangular ( CI 101–104), with convex lateral margins and rounded posterolateral corners (vs. the head of M. shixui Gu & Chen , sp. nov. is subrectangular ( CI 95–97), with projecting posterolateral corners); (2) the anterior margin of clypeus in M. shanyii Gu & Chen , sp. nov. nearly straight, lacking a median denticle (vs. arcuately concave with median denticle in M. shixui Gu & Chen , sp. nov.); (3) the eumetanotal spines of M. shanyii Gu & Chen , sp. nov. projects conspicuously above the dorsal outline (vs. M. shixui Gu & Chen , sp. nov. lacks such prominence); (4) propodeal spines differ in proportions — length equal to their basal width with upturned tips in M. shanyii Gu & Chen , sp. nov. (vs. length 2 times basal width and straight in M. shixui Gu & Chen , sp. nov.); (5) the postpetiole in M. shanyii Gu & Chen , sp. nov. exhibits strong anteroposterior compression (height> length) (vs. while height equal to length in M. shixui Gu & Chen , sp. nov.); (6) dorsum of head in M. shanyii Gu & Chen , sp. nov. exhibits rugulose-reticulated (vs. longitudinal striae in M. shixui Gu & Chen , sp. nov.); (7) punctate-rugulose lateroventral area of head (vs. faint striae with smooth interspaces in M. shixui Gu & Chen , sp. nov.); (8) mesosomal with anterior margin dorsum rugae in M. shanyii Gu & Chen , sp. nov. (vs. dense parallel longitudinal rugae in M. shixui Gu & Chen , sp. nov.).

Worker measurements.

(N = 5). HL 0.51–0.56, HW 0.54–0.58, CI 100–104, SL 0.43–0.45, SI 77–78, ED 0.07–0.08, MSL 0.62–0.66, PW 0.39–0.42, PL 0.17–0.18, PH 0.18–0.20, DPW 0.18–0.21, LPI 106–111, DPI 106–116, GL 0.88–0.91, TL 2.61–2.67.

Worker description.

Head. In full-face view, head rectangular (length> width), lateral margins slightly convex, posterior margin medially concave; posterolateral corners rounded and prominent. Mandibles with 6–7 teeth: apical two teeth robust; teeth 3–6 indistinct, basal tooth distinct but markedly smaller than apical teeth, with one denticle near inner margin. Clypeus projecting anteriorly beyond head margin, with distinct lateral teeth, anterior margin nearly straight, lacking median denticle. Frontal lobes weakly expanded laterally. Antennae 12 - segmented, scapes just reaching posterolateral corners of head. Eyes medium size, composed of 14–16 ommatidia. Mesosoma. In lateral view, mesosoma convex, eumetanotal spines stout, tooth-like, projecting above dorsal outline. Propodeal spines robust at base, tapering apically, length equal to their basal width, with tips slightly upturned. Propodeal spiracle diameter equal to half its distance to propodeal declivity. In dorsal view, pronotum convex anteriorly with prominent humeral corners; lateral margins gradually converging posteriorly to propodeal spines. Propodeal spines 1.7 times longer than their basal width; inter-spinal space broadly V-shaped. Metasoma. In lateral view, petiole distinctly higher than long, with posterodorsally directed tooth-like projection in middle; ventral margin convex with distinct subpetiolar process. Postpetiole with anterodorsal corner, dorsal margin straight, strongly compressed anteroposteriorly (height much> length). In dorsal view, both petiole and postpetiole wider than long; gaster with nearly straight anterior margin and rounded anterolateral corners. Sculpture. Mandibles and clypeus smooth and shining. Antennal scapes with dense rugae on proximal half, distal half smoother. Dorsum of head rugulose-reticulated; lateroventral area of head punctate-rugulose. Pronotal sides with oblique posterodorsally directed striae; mesopleura and metapleura with longitudinal rugae; mesosomal dorsum with coarse irregular rugae. Petiole and postpetiole with short longitudinal rugae; gaster smooth and shining. Pilosity and pubescence. Body with moderately dense erect hairs. Pubescence restricted to antennal club. Coloration. Predominantly black; genae and mid-lateral portions of gaster with longitudinal reddish-brown bands. Antennae and legs reddish-brown to dark brown.

Etymology.

The specific epithet is a genitive noun honoring Professor Shanyi Zhou, the renowned myrmecologist from Guangxi Normal University, for his significant contributions to Chinese ant taxonomy. The species name retains Professor Zhou’s personal name “ Shanyi ” in its pinyin romanization with Latin genitive suffix * - i *.

Distribution.

Hainan.

Figures

Figure 49. Myrmecina shanyii Gu & Chen, sp. nov. A. Mesosoma in dorsal view; B. Head in full-face view; C. Body in dorsal view; D. Body in lateral view.