Myrmecina yamanei

The species inhabits litter.

Identification
Okido, Ogata, and Hosoishi (2020) - Similar to Myrmecina insulana and Myrmecina sabahna (see the M. insulana identification section for details) but distinguished by a short antennal scape not reaching the occipital corner, scape width (SI) ≤ 77, and an anterior clypeal margin with a median process.

Distribution based on Regional Taxon Lists
Indo-Australian Region: Malaysia.

Nomenclature

 * . Myrmecina yamanei Okido, Ogata & Hosoishsi, 2020: 103, fig. 48 (w.) MALAYSIA.

Worker
Holotype worker. TL 2.12, HL 0.51, HW 0.48, CI 94, SL 0.37, SI 77, PW 0.37, ML 0.55. Paratype worker. TL 2.08, HL 0.49, HW 0.48, CI 98, SL 0.36, SI 75, PW 0.36, ML 0.53 (1 measured).

Head subrectangular, longer than broad in full-face view; median portion of occipital margin slightly concave; occipital corners rounded, not projected posteriorly. Masticatory margin of mandible bent at midlength (third small tooth or sixth tooth); apical tooth strong, third tooth robust, followed by 5 small teeth and a basal tooth. Dorsal surface of clypeus slightly concave; median portion of anterior margin feebly projected with a median process or three processes; lateral portion simple, lacking sharp ridge in front of antennal insertions. Anterior dorsal surface of labrum with paired small denticles distinctly, relatively close to each other. Frontal carinae virtually absent, indistinguishable from rugae on dorsum of head. Eyes small ovally, and moderately convex, varying in size with maximum diameter 0.06 mm and 12-14 ommatidia; malar space twice as long as diameter of eye or longer in profile; distance between occipital margin and posterior margin of eye four times as long as diameter of eye or longer. Antennal scape short, not reaching posterolateral corner of head; antennal flange weakly developed.

Dorsal outline of mesosoma slightly convex in profile. Pronotum without denticles; anterior portion marginate; anterior ventrolateral portion angulate. Furrow between pronotum and mesoepisternal projection broad. Eumetanotal spine present but small. Propodeal spine triangular, just reaching or slightly extending over vertical posteriormost limit of propodeum in profile. Propodeal lobe low. Propodeal spiracle medium-sized to large, situated near posterior margin of propodeum, distance between posterior margin of spiracle and posterior margin of propodeum variable. Petiole short, as long as or slightly longer than high in profile, slightly longer than broad in dorsal view; dorsal crest located at midlength in profile; subpetiolar process variously developed from weakly raised median longitudinal ridge to distinct projection. Postpetiole broader than petiole, 1.5 times longer than its length except for helcium in dorsal view; dorsal outline flattened or slightly convex in profile; ventral outline projected rectangularly with acute anterior apex.

Anterior margin of gaster not concave in dorsal view.

Head punctured with straight rugae diverging posteriorly; ventrolateral portion sculptured variable, with or without irregular rugae. Clypeus smooth and shining. Mesosoma punctured with parallel rugae which are thick and longitudinal. Forecoxa smooth and shining. Petiole and postpetiole with longitudinal rugae. First gastral segment smooth and shining. Head with more or less dense and short pilosity on dorsum. Mesosoma more or less with dense and short pilosity on dorsum, hairs of pronotum shorter than propodeal spine. Petiole without hairs on ventral surface. Postpetiole with 2-4 hairs on ventral surface. Body black, forecoxae black to dark reddish brown, mandibles, antennae and legs brown to yellowish brown.

Type Material
Holotype worker, MALAYSIA: Ulu Gombak, ca. 250 m alt., Selangor Prov., Malay Pen., 5. vii. 1999 (Sk. Yamane). Paratypes. 1 worker with same data as holotype; MALAYSIA: Neg. Sembilan, Pasoh For. Res., xi. 1994 (M. Brendell, K. Jackson & S. Lewis); Malaya, Selangor, Gombak, 15. x. 84 (C. Betts) (UMS; ; ).