Ooceraea hainingensis sp. nov.

Figs 1, 2, 3

Etymology.

The species epithet hainingensis refers to the type locality.

Type material.

Holotype: one worker ant; point mounted. Original label: “ China, Zhejiang, Haining, Qianjiang village, Yuemiao Mountain, 30.372187 ° N, 120.810766 ° E, nesting in the subterranean zone, 10. VI. 2022, Haoyu Liu leg. ”. Paratypes: five workers from the same colony as the holotype. These type specimens are deposited in the Insect Collection of Guangxi University (GXU), Nanning, Guangxi, China.

Description of the workers.

Measurements and indices: Holotype: HL 0.53, HW 0.46, SL 0.19, MW 0.32, ML 0.74, PL 0. 0.22, PH 0.36, PW 0.22, PPL 0.25, PPH 0.33, PPW 0.30, CI 87, SI 42, PI 1 59, PI 2 104, PPI 1 75, PPI 2 123, WI 135. Paratypes (N = 5): HL 0.50–0.56, HW 0.43–0.47, SL 0.18–0.26, MW 0.32, ML 0.66–0.73, PL 0.19–0.22, PH 0.33–0.37, PW 0.22–0.26, PPL 0.22–0.26, PPH 0.30–0.34, PPW 0.27–0.32, CI 82–88, SI 42–57, PI 1 52–63, PI 2 110–133, PPI 1 68–78, PPI 2 117–145, WI 117–131.

Head: In full-face view (Fig. 1 A), the cranium subrectangular, distinctly longer than broad; lateral sides weakly / very slightly convex; posterior margin weakly concave medially; posterolateral corners rounded. Mandibles subtriangular, and the masticatory margin lacks distinct denticles. Antennae 9 - segmented; scape short and clavate, reaching up to the mid-length of the cranium in full-face view. Antennal sockets fully exposed. Compound eyes and ocelli absent.

Mesosoma: Dorsum of mesosoma slightly convex in lateral view (Fig. 1 B). Pronotum in dorsal view (Fig. 1 C) with anterior margin rounded. Promesonotal suture and metanotal groove present (Fig. 2 A). Propodeum in dorsal view with posterior margin concave; propodeal lobe is well formed and roundly shaped (Fig. 2 B).

Metasoma: Petiole (abdominal segment II) in lateral view (Fig. 1 B) much higher than long when including subpetiolar process (PI 1, 52–66), with dorsal margin weakly convex. Petiole in dorsal view subrectangular (Fig. 1 C), slightly wider than long (PI 2, 104–132), with lateral sides weakly convex. Subpetiolar process in lateral view prominent and anteroventrally directed like a thumb, with posteroventral margin sublinear (Fig. 1 B, 2 B). Postpetiole (abdominal segment III) in lateral view subrectangular, much higher than long (PPI 1, 68–78), with dorsal and ventral margin weakly convex. Postpetiole in dorsal view almost trapezoidal, wider posteriorly, broader than long (PPI 2, 117–127), and wider than petiole (WI, 117–135), with lateral margins slightly convex. Postpetiolar tergite in lateral view consists of a convex dorsum that is larger than the sternite. The first gastral tergite (abdominal tergite IV) elongated elliptically in dorsal view, with its anterior margin concave and the lateral margin convex.

Sculpture: The head, mesosoma, petiole, and postpetiole with dense foveae, with foveae in mesosoma, petiole, and postpetiole slightly larger than in the head in lateral view. Posterior face of propodeum smooth. The first segment of the gaster (abdominal tergite and sternite IV) densely foveolate; with foveae somewhat smaller than those of cranium and mesosoma. Antennal scape and legs micropunctate. Legs roughly shagreened.

Pilosity: Body entirely densely covered with decumbent or standing hairs.

Color: Body light brown to dark reddish-brown; legs paler.

Recognition.

Ooceraea hainingensis sp. nov. is readily distinguishable from other described Ooceraea species by the following characteristics: 9 - segmented antenna; eyes absent in the worker caste; the promesonotum slightly convex; the promesonotal suture and metanotal groove obvious; and the subpetiolar process prominent and anteroventrally directed like a thumb with sublinear posteroventral margin.

Ooceraea hainingensis sp. nov. is generally similar to O. biroi, but these species differ in the shape of the subpetiolar process, promesonotal suture, and metanotal groove (Fig. 2).

Description of the dealate queen.

Measurement and indices: Dealate queen (N = 1). HL 0.55, HW 0.48, SL 0.25, EL 0.08, MW 0.41, ML 0.81, PL 0.22, PH 0.37, PW 0.22, PPL 0.28, PPH 0.36, PPW 0.25, CI 87, SI 51, PI 1 58, PI 2 104, PPI 1 77, PPI 2 92, WI 113.

Queen description: Similar to worker in structure, sculpture, coloration and pilosity, but differs from the worker by the following modifications: the body size slightly larger (HW 0.48 in dealate queen, 0.43–0.47 mm in workers; HL 0.55 in dealate queen, 0.50–0.56 mm in workers); compound eyes present approximately at mid-length of the head side; ocelli present and closely approximated (Fig. 3 A); mesosoma with unfused flight sclerites.

In lateral view (Fig. 3 B), the mesosoma dorsum slightly convex. In dorsal view, the mesoscutum subpentagonal (Fig. 3 C), with its lateral sides enclosed by the V-shaped posterior margin of the pronotum; notauli and parapsidal lines absent. The metanotum is narrow. The propodea dorsum with posterior margin concave.

Male. Unknown.

Habitat.

The type specimens are from a colony collected from the Yuemiao Mountain, Haining City of Zhejiang Province in China (30.372187 ° N, 120.810766 ° E). The collection site has relatively high canopy cover with low light penetration (Fig. 4 A). The temperature at the time of collection was 20 ° C. One queen and seventeen worker specimens were collected from the soil in a bamboo forest (Fig. 4 B).

Distribution.

Only known from the type locality.