Syscia reticularis Jaitrong, Wiwatwitaya et Yamane, 2020

Jaitrong, W., Wiwatwitaya, D. & Yamane, Sk., 2020, FIRST RECORD OF THE ANT GENUS SYSCIA ROGER, 1861 (HYMENOPTERA: FORMICIDAE) FROM THAILAND, WITH DESCRIPTIONS OF TWO NEW SPECIES, Far Eastern Entomologist 411, pp. 1-9 : 6-9

Syscia reticularis Jaitrong, Wiwatwitaya et Yamane , sp. n.

http://zoobank.org/NomenclaturalActs/ DFDCB076-7ADB-43B4-8124-62A74850F4C7

Figs 7–10

TYPE MATERIAL. Holotype – worker (THNHM-I-02624), S Thailand: Nakhon

Si Thammarat Province, Noppitam District, Krung Ching Waterfall, 20. V 2003, W.

Jaitrong leg., Colony no. WJT03-TH-332 ( THNHM). Paratypes: ten workers, same data as holotype (THNHM-I-02625, THNHM-I-19552 to THNHM-I-19559, and gkhla Province, Had Yai District, Prince of Songkhla University forest , 17.III 2007,

Sk. Yamane leg., Colony no. TH07-SKY-74; One worker ( THNHM), Malaysia:

Malay Peninsula, Selangor, Ulu Gombak, Maschwitz valley, 5.X 2002, Sk. Yamane leg.

profile view; 8 – head in full-face view; 9 – body in dorsal view.

DESCRIPTION. WORKER (7–9).

MEASUREMENTS. Holotype: HL0.63; HW 0.50; SL 0.30; MW 0.40; ML

0.73; PL 0.30; PH 0.40; PW 0.30; PPL 0.36; PPH 0.43; PPW 0.36; CI 79; SI 60;

PI1 75; PI2 100; PPI1 85; PPI2 100; WI 122. Paratypes (n = 7): HL 0.56–0.63; HW

0.46–0.50; SL 0.26–0.33; MW 0.36–0.40; ML 0.73–0.76; PL 0.28–0.30; PH 0.40;

PW 0.30–0.33; PPL 0.36–0.38; PPH 0.41–0.43; PPW 0.36; CI 79–82; SI 57–67;

PI1 71–75; PI2 100–111; PPI1 85–88; PPI2 96–100; WI 110–122.

Size and color. Medium size (HW 0.46–0.50 mm; ML 0.73–0.76 mm). Body dark reddish brown; legs and antenna paler. Hairs pale brown.

Structure. Head in full-face view elliptical, longer than broad; lateral margin convex; posterior margin almost straight. Antenna 11-segmented with enlarged apical segment (XI) which is almost as long as IV–X combined; scape short, when folded back reaching mid-length of head in full-face view; antennal segment II almost as long as broad; III–VI broader than long. Frontal carinae short and narrow, reaching less than half length of head, in profile sharply elevated in anterior half, low and vestigial in posterior half. Parafrontal ridge prominently produced anteriad in dorsal view. Clypeus short, its anterior margin weakly convex. Compound eye and ocelli completely absent. Mandible triangular, its masticatory margin with a series of in-

conspicuous small denticles. Mesosoma rather robust, subrectangular, seen from above almost parallel - sided; with mesosoma in profile view, dorsal outline weakly convex; promesonotal suture and metanotal groove completely absent; mesopleuron not demarcated from metapleuron. Propodeal declivity flat, encircled with indistinct rim. Petiole in dorsal view almost as long as broad, almost parallel - sided; in profile view, petiole including subpetiolar process clearly shorter than high, subrectangular,

convex dorsally, with flattened anterior face. Subpeiolar process in profile subrectangular with its ventral outline concave. Postpetiole in dorsal view slightly larger than petiole, subrectigular, slightly longer than broad; in profile view, postpetiole slightly shorter than high, its dorsal outline weakly convex. Postpetiolar sternite in profile view low, its ventral margin convex; anteroventrally produced as a blunt angle directed downward and forward. Abdominal tergite III (= first gastral tergite) elongate -

oval; in dorsal view, its anterior margin clearly concave and lateral margins convex.

Sculpture. Entire body finely reticulate with deep bottoms ( Figs 7–10 ). Antennal scape, outer face of mandible and legs punctate.

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

REMARKS. Syscia reticulata is a distinct species. It can be distinguished from others species by the following characteristics: body entirely reticulate, with deep bottoms (body covered with punctures or shallow fovea in other species); petiole slightly smaller than postpetiole; in profile view postpetiole rounded.

HABITAT. The type series was collected from a rotting wood on the forest floor in a lowland rainforest.

DISTRIBUTION. Thailand (Nakhon Si Thammarat Province) and Malaysia (W

Malaysia).

ETYMOLOGY. The species epithet “ reticularis ” is a Latin word meaning reticulate. This refers to the finely reticulate body of this species.

Figures

Figs 7–9. Syscia reticularis sp. n., worker (holotype, THNHM-I-02624). 7 – body in

Figs 10, 11. Gaster of workers. 10 – Syscia reticulata sp. n.; 11 – S. chaladthanyakiji sp. n.