Ooceraea quadridentata Yamada, Luong et Eguchi, 2018: 18

Jaitrong, W., Yamane, Sk. & Wiwatwitaya, D., 2021, A new species and a new record of the ant genus Ooceraea Roger, 1862 (Hymenoptera: Formicidae: Dorylinae) from Thailand, Far Eastern Entomologist 441, pp. 1-10 : 3-6

Ooceraea quadridentata Yamada, Luong et Eguchi, 2018: 18 , figs. 1–11. Holotype and 11

paratype workers (two paratypes were examined), Dak Lak Province, Nam Kar Nature

Reserve, 12.277°N, 108.094°E, ca. 545 m alt., 11.X 2017, A. Yamada leg., colony no.

AKY11x17 - 114 (AKYC, ACEG, IEBR, MCZC, MHNG).

MATERIALS EXAMINED. Vietnam: Khanh Hoa, Hon Ba National Park, (900

m alt.), 12º06ˈN, 108º58ˈE, 20 II.2014, S. Hosoishi leg., SH14-Vie-16 (THNHM-I-

25731, THNHM). Northeastern Thailand: Nakhon Ratchasima Prov., Wang Nam

Kheao Dist. , Udom Sab Subdist., 14º28'5''N, 101º54'15''E, 22.VI 2018, W. Jaitrong leg. WJT220618 - 1 (9 ergatoid queens (THNHM-I-25732 to THNHM-I-25740), 14

workers (THNHM-I-25741 to THNHM-I-25754), THNHM). Eastern Thailand:

Chachoengsao Prov., Khao Ang Reu Nei W.S., Lumchangwat Station, 26.IV 2003,

W. Jaitrong leg., WJT03 - TH - 229 (7 workers, THNHM-I-25755 to THNHM-I-

25761, THNHM).

view; B – body, dorsal view; C – head in full-face view; D – postpetiole and abdominal tergite IV, dorsal view.

MEASUREMENTS AND INDICES. Worker (n = 10): HL 0.76–0.83, HW 0.66–

0.73, SL 0.33–0.36, MW 0.46–0.53, ML 0.83–0.99, PL 0.33–0.36, PH 0.40–0.43,

PW 0.30–0.36, PPL 0.36–0.40, PPH 0.36–0.46, PPW 0.33–0.43, CI 87–91, SI 45–

55, PI1 77–85, PI2 90–110, PPI1 79–100, PPI2 91–109, WI 109–120. Ergatoid queen (n = 5): HL 0.86–0.89, HW 0.76–0.79, SL 0.36–0.40, EL 0.10, MW 0.59–

0.63, ML 1.02–1.06, PL 0.36, PH 0.50, PW 0.40–0.43, PPL 0.43, PPH 0.46–0.50,

PPW 0.43–0.46, CI 88–89, SI 48–50, EI 13, PI1 73, PI2 109–118, PPI1 89–93,

PPI2 100–108, WI 108.

DIAGNOSIS. Worker ( Fig. 1 ). Body rather large with head width 0.66–0.73 mm,

dark reddish brown; anternna 11-segmented; propodeal declivity deeply concave,

margined with conspicuous lateral ridges, each of which armed with two inconspicuous denticles; dorsal and lateral faces of head deeply foveolate - reticulate, foveae relatively large; dorsal and lateral faces of mesosoma foveolate; foveae somewhat shallower and more sparsely distributed than those of head; propodeal declivity smooth; abdominal tergite and sternite IV densely foveolate; foveae somewhat smaller than those of head.

DESCRIPTION. Ergatoid queen ( Fig. 2 ). Size and color. Relatively large (HW

0.66–0.73 mm; ML 0.83–0.99 mm). Body entirely dark reddish brown; hairs golden brown.

lateral view; B – body, dorsal view; C – head in full-face view; D – postpetiole and abdominal tergite IV, dorsal view.

Structure. Head in full - face view subrectangular, slightly longer than broad;

lateral margin convex; posterior margin weakly concave. Antenna 11 - segmented with enlarged apical segment (XI) which is almost as long as V–X combined; scape short, when laid straight back reaching mid - length of head in full - face view; antennal segment II almost as long as broad; III–V broader than long. Frontal carinae well developed, parallel in anterior 2 / 3, fused to form a single carina in posterior 1 / 3,

extending less than half length of head. Parafrontal ridge prominently produced ante-

riad in dorsal view. Ventrolateral margin of head in profile view weakly concave.

Clypeus short, its anterior margin concave. Compound eye present, located anterior to med - length of head, circular with 10–11 ommatidia along the longest axis. Ocelli present, distance between median ocellus and lateral ocelli as long as distance between lateral ocelli. Mandible triangular, its masticatory margin with a series of inconspicuous small denticles. Mesosoma rather robust, in profile view its dorsal outline weakly convex; promesonotal suture distinct; metanotal groove indistinct;

mesopleuron clearly demarcated from lateral face of pronotum. Propodeal declivity concave, margined with conspicuous lateral ridges, each of which armed with two inconspicuous denticles. Petiole in profile view higher than long when including subpetiolar process; dorsal margin weakly convex; in dorsal view, petiole in dorsal view subrectangular, almost as long as broad, lateral margin slightly convex. Sub-

peiolar process in profile subrectangular with conspicuous posteroventral projection.

Postpetiole in profile view, subrectangular almost as long as high; dorsal margin weakly convex; in dorsal view subrectangular, almost as long as broad and slight broader than petiole. Postpetiolar sternite in profile view low, ventral margin weakly convex; anteroventrally produced as a blunt angle directed downward and forward.

Abdominal tergite IV (= first gastral tergite) elongate - elliptical, in dorsal view, its anterior margin concave and lateral margin convex.

Sculpture. Dorsal and lateral faces of head deeply foveolate - reticulate; foveae relatively large; mandible punctate with a few foveae; antenna punctate. Pronotal flange partially punctate; dorsal and lateral faces of mesosoma foveolate; foveae somewhat shallower and more sparsely distributed than those of head; propodeal declivity smooth; legs punctate but shiny. Dorsal and lateral faces of petiolar tergite,

and postpetiole coarsely and shallowly foveolate - reticulate. Abdominal tergite and sternite IV (= first gastral segment) densely foveolate; foveae somewhat smaller than those of head.

Pilosity. Body entirely covered with long decumbent and standing hairs.

REMARKS. Specimens collected from Thailand agree well with the two paratypes examined by us but are somewhat smaller than the latter in body size. The anterior portion of abdominal segment IV is slightly broader than in the paratypes .

DISTRIBUTION. Thailand (new record). – Vietnam (Yamada et al., 2018).

HABITAT. In Thailand, this species was found nesting in rotten logs on the forest floor in a plantation and dry evergreen forest.

Figures

Fig. 1. Ooceraea quadridentata, non-type worker (THNHM-I-25754). A – body, lateral

Fig. 2. Ooceraea quadridentata, non-type ergatoid queen (THNHM-I-25732). A – body,