Aenictus doydeei Jaitrong & Yamane, 2011

Jaitrong, Weeyawat & Yamane, Seiki, 2012, Review of the Southeast Asian species of the Aenictus javanus and Aenictus philippinensis species groups (Hymenoptera, Formicidae, Aenictinae), ZooKeys 193, pp. 49-78 : 52-54

Aenictus doydeei Jaitrong & Yamane, 2011 Figs 17A

Aenictus doydeei Jaitrong & Yamane, in Jaitrong et al. 2011: 319, figs 7-9.

Types.

Holotype and 61 paratype workers from a plantation, 211 m, Sivilay Village, Naxaythong Dist., Vientiane, Laos, 18°16'10"N, 102°26'36"E, 10.VI.2010, W. Jaitrong leg., WJT10-LAO13 (AMK, BMNH, KKIC, MCZC, SKYC, THNHM, examined).

Measurements.

Holotype: TL 3.40 mm; HL 0.70 mm; HW 0.65 mm; SL 0.40 mm; ML 1.00 mm; PL 0.28 mm; CI 93; SI 62.

Paratype workers(n= 9): TL 2.90-3.40 mm; HL 0.53-0.70 mm; HW 0.48-0.65 mm; SL 0.28-0.40 mm; ML 0.75-1.00 mm; PL 0.23-0.28 mm; CI 91-95; SI 55-62.

Description of worker

(holotype and paratypes).Head in full-face view almost as long as broad, with sides convex and posterior margin almost straight or feebly concave; seen in profile occipital corner of head rounded. Antennal scape reaching midlength of head; antennal segment II longer and narrower than each of III–VI; terminal segment (X) about 2.5 times as long as broad. Anterior margin of clypeus bearing 9-10 denticles. Masticatory margin of mandible with 3 acute teeth including a large apical tooth; basal margin lacking denticles. Mesosoma seen from above broader anteriorly than posteriorly; promesonotum laterally edged, in profile weakly convex dorsally and sloping gradually to propodeal junction; in profile propodeum slightly lower than promesonotum and almost flat dorsally; suture between mesopleuron and metapleuron completely absent; propodeal junction angulate, right-angled; declivity of propodeum shallowly concave, encircled by a thin rim. Petiole almost as long as high, its dorsal outline slightly elevated posteriorly; subpetiolar process well developed, subrectangular, its ventral margin almost straight and longer than posterior margin; postpetiole seen in profile subrectangular and slightly larger than petiole.

Head entirely smooth and shiny. Dorsal surface of pronotum smooth and shiny, lateral face superficially reticulate and shiny; mesothorax, metapleuron and propodeum densely microreticulate. Petiole entirely microreticulate. Postpetiole microreticulate except for a small smooth and shiny area on dorsal surface.

Head and mesosoma dorsally with relatively sparse standing hairs mixed with sparse short hairs; longest pronotal hairs 0.18-0.20 mm long. Head, mesosoma, petiole and postpetiole reddish brown; gaster yellowish brown; propodeum darker than other parts

Non-type material examined.

VIETNAM: Dong Nai Prov., S. Cat Tien N.P., Crocodile Lake Trail, 18.X.2004, K. Eguchi leg., Eg04-VN-707 (SKYC). THAILAND: NE. Thailand, Loei Prov., Phu Rur Dist., disturbed area, 10.IV.2008, P. Kosolpanyapiwat leg., PKK08-TH102 (SKYC, THNHM); Chaiyaphum Prov., Phu Kheao Dist., Agricultural area, 30.I.1999, W. Jaitrong leg., WJT99-AG22 (SKYC, THNHM); NE. Thailand, Nakhon Ratchasima Prov., Sakaerat ERS, 10.VII.1999, Sk. Yamane leg., TH99-SKY-19 (SKYC, THNHM).

Distribution

. Vietnam (new record), Laos and Thailand (Fig. 7A).

Bionomics.

The type series from Laos and three colonies from Thailand were collected from disturbed areas in the night. Thus Aenictus doydeei is very probably nocturnal. Jaitrong et al. (2011) reported that this species preyed on Pheidole plagiaria .

Remarks.

This species is closely related to Aenictus javanus , Aenictus longinodus , and Aenictus nishimurai in terms of body size and coloration. Aenictus doydeei , however, is easily distinguished from Aenictus javanus and Aenictus longinodus as follows: occipital margin of head in profile rounded (Fig. 1E), while angled in Aenictus javanus (Fig. 3D); petiole almost as long as high, but clearly longer than high in Aenictus javanus and Aenictus longinodus (Figs 3B, 4B, D). Aenictus doydeei is most similar to Aenictus nishimurai , but is clearly larger than Aenictus nishimurai with a slight overlap, and has the lateral face of the pronotum that is smooth but reticulated (almost smooth in Aenictus nishimurai ). Aenictus doydeei is sympatric with Aenictus nishimurai in Vientiane province, Laos and in northeastern Thailand.