Myrmecina gaoligongensis Liu, 2022

Liu, Cong, Fischer, Georg, Liu, Qing, Peng, Yan-Qiong, Economo, Evan P. & Guénard, Benoit, 2022, Updating the taxonomy of the ant genus Myrmecina (Hymenoptera, Formicidae) in China with descriptions of three new species, Zootaxa 5182 (2), pp. 152-164 : 158-160

Myrmecina gaoligongensis Liu , sp. nov.

Figure 4 .

Type material. Holotype, pinned worker, China, Yunnan, Gaoligong Shan Mountains, Tiantan Shan , 25.30460N, 098.79349E, 1815 m, mountain forest, leaf litter, 03.VII.2019 (C. Liu & G. Fischer) ( ISAS: MCZENT00759990 ).

Paratypes. 6 pinned workers, China, Yunnan, Gaoligong Shan Mountains, Tiantan Shan, 25.30460N, 098.79349E, 1815 m, mountain forest, leaf litter, 03.VII.2019 (C. Liu & G. Fischer) ( ISAS: MCZ-ENT00759803; CAS: MCZ-ENT 00759804; MCZ: MCZ-ENT00759805); China, Yunnan, Shan Gaoligong Mountains, Tiantan Shan, 25.31004N, 098.79469E, 1472 m, temperate mountain forest, leaf litter, 05.VII.2019 (C. Liu & G. Fischer) ( ISAS: MCZ-ENT00759824; CAS: MCZ-ENT 00759889; MCZ: MCZ-ENT00759890).

Diagnosis. Myrmecina gaoligongensis differs from other Chinese members of Myrmecina by the following combination of characters: propodeal spine triangular, shorter than broad at the base and pointing posteriorly; petiole node in dorsal face-view subrectangular, 1.5 times longer than wide; postpetiole as long as broad; head with dense punctation and weak longitudinal rugae; ventrolateral area of head strongly punctate; gaster smooth and shiny.

Worker measurements. (N=7). TL 2.25–2.27; HL 0.53–0.55 HW 0.53–0.55; MaL 0.30–0.32; SL 0.40–0.43; EL 0.05–0.07; WL 0.65–0.68; PNW 0.40–0.43; PNH; 0.28–0.31; MW 0.20–0.25; PSL 0.10–0.12; PTL 0.23–0.25; PTW 0.15–0.17; PTH 0.13–0.15; PPL 0.18–0.2; PPW 0.18–0.2; PPH 0.18–0.2; CI 100–103; SI 76–81; MaI 57–61; PI 67–70; PPI 100–103.

Worker description. Head. Head subrectangular, as long as broad in full-face view (CI 100 - 103); median portion of occipital margin concave; occipital corners rounded, not projected posteriorly. Mandible triangular; masticatory margin with large apical tooth and robust third tooth, followed by 7 denticles; anterior margin of clypeus concave, with three distinct processes; lateral portion of clypeus lacking a sharp ridge in front of antennal insertions. Anterior dorsal surface of labrum with two small denticles. Frontal carinae virtually absent, indistinguishable from rugae on dorsum of head. Eyes relatively small with 6 ommatidia and maximum diameter 0.05 mm; antennae 12- segementd, with 3-segmented club; antennal scape short, reaching the posterolateral corner of the head.

Mesosoma. Dorsum of mesosoma slightly convex in profile view; pronotum without denticles; propleuron angular without forming a distinct small tooth; eumetanotal spine reduced or vestigial, visible only as a small denticle; propodeal spines triangular, shorter than broad at their bases and pointing posteriorly; propodeal declivity strongly concave; propodeal lobes with high lateral walls. Propodeal spiracle large, situated near the base of propodeal spine. Metapleural bulla well developed and covering most of the propodeal lobe.

Metasoma. Petiole in dorsal view rectangular, 1.5 times longer than broad; anterodorsal slope of petiole in profile view almost straight with posterodorsal face concave, both faces separated by a sharp little peak and ridge; Sternopetiolar process with a convex lobe medially and small point anteriorly; postpetiole in dorsal view as broad as long, shorter than petiolar node. Sternopostpetiolar process weakly present with a small denticle pointing anteriorly. Anterior margin of first gastral tergite weakly concave in dorsal view.

Sculpture. Head in full-face view densely punctate, with weak, longitudinal rugae; lateroventral area of head densely punctate; mandible and clypeus smooth and shiny; in profile view, mesosoma with irregular, longitudinal, and posteriorly converging rugae; forecoxae smooth and shiny; petiole, and postpetiole with longitudinal rugae; mesosoma, petiole, and postpetiole in dorsal view with longitudinal rugae; gaster smooth and shiny.

Pilosity and pubescence. Body covered with abundant erect hairs. Antenna with abundant suberect and erect hairs. Mandible with numerous thin and long hairs, basal masticatory margin with few spatulate hairs. Head and Mesosoma with dense and short erect pilosity on dorsum. Petiole and Postpetiole without hairs on ventral surface. All legs with numerous suberect to erect hairs. Gaster with dense and short erect pilosity on both dorsum and ventral.

Coloration. Body mostly black with yellow-brown mandibles, antennae, and legs.

Etymology. The species is named after the mountain range where it was collected.

Distribution and ecology. At present, the new species is known only from the Gaoligong Shan Mountains in Yunnan, China. The type locality is a montane forest on Tiantan Shan Mountain, situated at an elevation range from 1400 to 1800 m. Four workers of the new species were collected from a leaf litter extraction at 1800 m altitude, and the other three from a leaf litter sample at 1400 m. Nothing specific is known about its ecology.

Figures

FIGURE 4. M. gaoligongensis sp. nov. (MCZ-ENT00759990). (A) Body in profile view. (B) Body in dorsal view. (C) Head in full-face view. (D) Distribution map in SE Asia.