Myrmecina insulana

Inhabits the soil and litter.

Identification
Okido, Ogata, and Hosoishi (2020) - Myrmecina insulana does not belong to a species complex. It is similar to Myrmecina sabahna and Myrmecina yamanei by eye size, shape and sculpture of the first gastral segment, relative length of the antennal scape, and sculpture of the mesosoma. Among these species, M. insulana can be distinguished by the transverse rugae on the ventrolateral portion of the head.

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

Nomenclature

 * . Myrmecina insulana Okido, Ogata & Hosoishsi, 2020: 53, fig. 23 (w.) MALAYSIA.

Worker
Holotype. TL 2.33, HL 0.56, HW 0.51, CI 91, SL 0.43, SI 84, PW 0.38, ML 0.61. Paratype. TL 2.22-2.37, HL 0.53-0.58, HW 0.51-0.53, CI 92-97, SL 0.43-0.45, SI 82-88, PW 0.37-0.40, ML 0.58-0.59 (4 measured).

Head subrectangular, longer than broad in full-face view; median portion of occipital margin 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 not concave; median portion of anterior margin feebly projected with or without median paired 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 very small circularly and usually convex moderately, varying in size with maximum diameter 0.06-0.08 mm and 10-11 ommatidia; malar space twice as long as diameter of eye or longer in profile; distance between occipital margin and posterior margin of eye distinctly four times as long as diameter of eye or longer. Antennal scape short, not or just reaching posterolateral corner of head; antennal flange fully developed.

Dorsal outline of mesosoma convex in profile. Pronotum with or without denticle; anterior portion marginate; anterior ventrolateral portion projected. Furrow between pronotum and mesoepisternal projection broad. Eumetanotal spine present but small. Propodeal spine triangular, variable in length, usually extending over vertical posteriormost limit of propodeum in profile. Propodeal lobe low. Propodeal spiracle large, situated near base of propodeal spine, distance between posterior margin of spiracle and posterior margin of propodeum longer than diameter of the spiracle. 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 slightly broader than petiole 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 with wavy rugae which are thin; ventrolateral portion with transverse, or vertical rugae sometimes unclearly. Clypeus smooth and shining. Mesosoma with wavy rugae which are thick. Forecoxa smooth and shining. Petiole and postpetiole with longitudinal rugae. First gastral segment smooth and shining. Head with dense and short pilosity on dorsum. Mesosoma 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. Head and mesosoma black, petiole and postpetiole reddish brown, mandibles, antennae and legs yellowish brown.

Type Material
Holotype worker, MALAYSIA: Mahua Waterfall area, ca. 1000 m alt., Crocker Range N. P., Sabah, 5. xi. 2000 (J. Fellowes). Paratypes. 2 workers and 1 queen with same data as holotype; 2 workers with same data as holotype but (H. Okido); MALAYSIA: Sabah, Kinabalu N. P., Poring Hot Springs, East Ridge, 560 m, 17. viii. 95 (C. Brühl); Danum Valley, Sabah, Borneo, 29. viii. 1995 (H. Okido); Sayap Kinabalu, ca. 1000 m alt., Sabah, Borneo, 14. vii. 1996 (Sk. Yamane); Sayap Kinabalu, ca. 1000 m alt., Sabah, Borneo, 14. vii. 1996, S-17 (K. Eguchi) UMS,,.