Myrmecina pierceae 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 : 160-163

Myrmecina pierceae Liu , sp. nov.

Figure 5 .

Type material. Holotype, pinned worker, China, Yunnan, Gaoligong Shan Mountains, Tiantan Shan , 25.40230N, 98.71899E, 2180 m, mountain forest, leaf litter, 05.VII.2019 (C. Liu & G. Fischer) ( ISAS: MCZ-ENT00759962).

Paratypes. 3 pinned workers (same data as holotype) ( ISAS: MCZ-ENT00759959; CAS: MCZ-ENT 00759960; MCZ: MCZ-ENT00759961) .

Diagnosis. The new species is morphologically distinct from all the other species in China. Myrmecina pierceae differs from other members of Myrmecina by the following combination of characters: propodeal spines triangular, in lateral view shorter than broad at their bases and pointing posteriorly; petiole node in dorsal view subrectangular, 1.5 times longer than wide; face with thin longitudinal rugae curving towards occipital corners; posterior ventrolateral area of head smooth and shiny, with 1 or 2 longitudinal rugae visible in lateral view; gaster smooth and shiny.

Worker measurements. (N=4). TL 2.49–2.56; HL 0.58–0.6; HW 0.58–0.6; MaL 0.28–0.30; SL 0.50–0.55; EL 0.08–0.08; WL 0.78–0.83; PNW 0.45–0.46; PNH 0.33–0.34; MW 0.30–0.40; PSL 0.15–0.18; PTL 0.25–0.27; PTW 0.18–0.18; PTH 0.20–0.25; PPL 0.15–0.20; PPW 0.23–0.25; PPH 0.20–0.23; CI 100; SI 87–92; MaI 48–49; PI 72–88; PPI 123–150.

Worker description. Head. In full-face view, head subrectangular, as long as broad (CI 100); median portion of occipital margin weakly concave; occipital corners rounded, not projecting posteriorly; mandible triangular; masticatory margin with large apical tooth and robust third tooth, followed by 5 denticles; anterior margin of clypeus concave, with a median process; 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 10 ommatidia and maximum diameter 0.08 mm; antennae 12- segmented, with 3-segmented club; antennal scape short, not reaching the posterolateral corner of head.

Mesosoma. In profile view, mesosomal dorsum convex; 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. In profile view, petiole in dorsal view rectangular, longer than broad; anterior slope of the petiole almost straight with posterodorsal face concave; dorsal outline of postpetiole flat to weakly convex; petiole longer than postpetiole; in dorsal view, postpetiole 1.5 times broader than long; sternopostpetiolar process weakly present with a small denticle pointing anteriorly. Anterior margin of first gastral tergite weakly concave.

Sculpture. Head in full-face view with distinct longitudinal rugae posteriorly curving towards occipital corners; ventrolateral area of head smooth and shiny, with 1 or 2 longitudinal rugae; clypeus smooth and shiny; mesosoma, petiole, and postpetiole with coarse longitudinal rugae dorsally and some oblique or irregular rugae laterally; forecoxae smooth and shiny; first gastral tergite and sternum 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 black with yellowish-brown mandibles, antennae, and legs.

Etymology. The new species is dedicated to Prof. Naomi Pierce and her contributions to entomology and myrmecology. We appreciate her great support of the first author’s studies on the ant biodiversity in China’s Hengduan Mountains.

Distribution and ecology. At present, the new species is only known from one collection site in the Gaoligong Shan Mountains in Yunnan, China. The type locality is a montane forest on Tiantan Shan Mountain, situated at an elevation of about 2200 m. Five workers of the new species were collected from one leaf litter sample. Unfortunately, there is no additional information about its ecology.

Figures

FIGURE 5. M. pierceae sp. nov. (MCZ-ENT00759962). (A) Body in profile view. (B) Body in dorsal view. (C) Head in fullface view. (D) Distribution map in SE Asia.