Calyptomyrmex laotius

The type series of this species was collected from leaf litter and soil surface in a dry evergreen forest at an elevation of ca. 300 m above sea level during the rainy season.

Identification
Jaitrong & Yamane (2018) - The hairs on head and body are fine (same width through entire length), simple and blunt at the apex. The promesonotal hairs are much longer, often more than two times as long as those on the head. The propodeal spine in profile is triangular and short, shorter than broad at the base. The entire head and promesonotum are covered with dense, fine, deep punctures or fine macropunctures. The first gastral tergite is reticulate and opaque.

Calyptomyrmex laotius can be easily distinguished from punctures on the head and promesonotum. Calyptomyrmex laotius is most similar to Calyptomyrmex rectopilosus in general appearance, but very distinct. Calyptomyrmex laotius can be easily distinguished from Calyptomyrmex rectopilosus punctures (with macropunctures and bearing several longitudinal rugae on dorsa of head and mesosoma in Calyptomyrmex rectopilosus); distinctly larger with HW 0.76–0.79 (0.56–0.66 in Calyptomyrmex rectopilosus); promesonotal hairs often 2 times as long or more as those on head (almost as long as those on head in Calyptomyrmex rectopilosus); promesonotum with 12–14 hairs (more than 20 in Calyptomyrmex rectopilosus).

Distribution based on Regional Taxon Lists
Oriental Region: Laos.

Nomenclature

 * . Calyptomyrmex laotius Jaitrong & Yamane, 2018: 133, figs. 1-3 (w.) LAOS.

Worker
Holotype: CFW 0.13, HL 0.73, HW 0.76, ML 0.69, MTL 0.36, PetL 0.17, PetW 0.30, PronW 0.56, SL 0.36, CI 104, PetI 180, SI 47. Paratypes (n = 4): CFW 0.12 – 0.13, HL 0.69 – 0.76, HW 0.76–0.79, ML 0.69–0.73, MTL 0.36–0.38, PetL 0.17– 0.20, PetW 0.30 – 0.36, PronW 0.56 – 0.59, SL 0.33–0.36, CI 104–110, PetI 180–200, SI 42–46.

Holotype and paratypes - Head in frontal view almost as long as broad or slightly shorter than broad, subtriangular, broader posteriorly, with straight posterior margin and convex posterolateral corner; antennal scrobe deep and broad, with dorsal and posterior margins lamellate; mandible subtriangular, masticatory margin with large apical tooth followed by medium-sized subapical tooth, a smaller tooth, diastema, and a series of 4–5 denticles, the series reduced in size toward basal tooth; basal margin of mandible almost straight, lacking denticles; eyes at ventral margin of antennal scrobe, relatively small, with 4–5 ommatidia in greatest diameter; scape short, broadest at mid-length. Mesosoma short, with strongly convex dorsal outline; propodeal spines triangular and short, shorter than broad at base; propodeal outline almost straight; in dorsal view petiolar node subrectangular, much broader than long, convex lateral margins. punctures on meso- and metapleura larger than those on head and pronotum; dorsalmost portion of metapleura with several short irregular rugae; antennal scrobes and coxae with hairs of similar lengths; promesonotum with 12–14 longer hairs (often > 2 times as long as those on head); ventral surface of head with sparse, short, appressed hairs; antennae with dense short pubescence, scapes with 3 – Entire body dark reddish brown to dark brown; legs, terminal segment of antennae (XI) than other parts.

Type Material
Holotype worker (THNHM-I-00208, deposited in ), Laos, Vientiane Province, Pak-Gnum Distrist, Phang Dang Village, 13 June 2010, W. Jaitrong leg. Paratypes: two workers, same data as holotype (THNHM-I-00209 and THNHM-I-00210, deposited in THNHM); two workers, same locality and date, Sk. Yamane leg. (THNHM-I-00211 and THNHM-I-00212, deposited in and THNHM, respectively); two workers, same locality and date, Sk. Yamane leg. (SKYC).

Etymology
The specific epithet is an adjective meaning "of Laos".

References based on Global Ant Biodiversity Informatics

 * Jaitrong W., and S. Yamane. 2018. A new species of the ant genus Calyptomyrmex Emry, 1887 (Hymenoptera: Formicidae: Myrmicinae) from Laos and new records of C. rectopilosus from Thailand and Hong Kong. Nat. Hist. Bull. Siam Soc. 62(2): 131-139.