Myrmecina grandis

Aoki & Ito (1997) reported that this species had a myrmecophilous oribatid mite Protoribates myrmecophilus, which was also found in the nest of Myrmecina maryatiae (Myrmecina sp. B). Ergatogynes are present in M. grandis.

Identification
Okido, Ogata, and Hosoishi (2020) - Myrmecina grandis does not belong to any Myrmecina species complex. It is distinguished from other Myrmecina by having a straight masticatory margin of the mandible, a simple anterior margin of its smooth and shining first gastral tergum, a short antennal scape just reaching occipital corner, a much projected anterior clypeal margin with three distinct processes, and a medium-sized eye.

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

Nomenclature

 * . Myrmecina grandis Okido, Ogata & Hosoishsi, 2020: 46, fig. 19 (w.) INDONESIA.

Worker
Holotype. TL 3.47, HL 0.86, HW 0.75, CI 87, SL 0.70, SI 94, PW 0.50, ML 0.91. Paratype. TL 3.30-3.60, HL 0.79-0.90, HW 0.74-0.82, CI 88-93, SL 0.70-0.75, SI 91-98, PW 0.47-0.51, ML 0.90-0.96 (11 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 straight; apical tooth strong, third tooth robust, followed by 6 small teeth. Dorsal surface of clypeus not concave; median portion of anterior margin much projected with distinct three processes; lateral portion simple, lacking sharp ridge in front of antennal insertions. Anterior dorsal surface of labrum with paired denticles, close to each other. Frontal carinae virtually absent, indistinguishable from rugae on dorsum of head. Eyes medium-sized and moderately convex, varying in size with maximum diameter 0.11-0.13 mm and 7-8 ommatidia; malar space twice as long as diameter of eye in profile; distance between occipital margin and posterior margin of eye three times as long as diameter of eye or longer. Antennal scape short, just reaching posterolateral corner of head; antennal flange fully developed.

Dorsal outline of mesosoma convex in profile. Pronotum with denticles on dorsolateral portion, but variable, sometimes reduced; anterior portion marginate; anterior ventrolateral portion not angulate. Furrow between pronotum and mesoepisternal projection narrow. Eumetanotal spine present. Propodeal spine triangular, slightly longer than broad at base, 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 much longer than diameter of spiracle. Petiole short, as long as or slightly longer than high in profile, and longer than broad in dorsal view; dorsal crest located at midlength in profile; subpetiolar process usually present, bearing acute anterior apex. Postpetiole broader than petiole and expanded anteriorly in dorsal view; anterior portion sharply raised in profile; ventral outline slightly projected rectangularly.

Anterior margin of gaster not concave in dorsal view; first gastral sternum simple without median longitudinal ridge.

Head usually with straight rugae distinctly, sometimes weakly waved; ventrolateral portion smooth and shining. Clypeus smooth and shining. Mesosoma with straight rugae longitudinally. Forecoxa smooth and shining. Petiole and postpetiole with a few rugae. First gastral segment smooth and shining. Head with relatively dense and long pilosity on dorsum. Mesosoma with dense and long pilosity on dorsum, hairs of pronotum slightly shorter than propodeal spine. Petiole without hairs on ventral surface. Postpetiole with 4-8 hairs on ventral surface. Head and mesosoma black, antennal scape, petiole, postpetiole and gaster reddish brown, mandibles, antennal funiculus and legs yellowish brown to brown.

Type Material
Holotype worker, INDONESIA: Ulu Gadut, Padang, W-Sumatra, 17. viii. 1996, 19. ii. 1997 fixed, FI96-379 (K. Ohkawara) (Bogor Zoological Museum, Bogor, Indonesia). Paratypes. numerous workers and ergatogynes with same data as holotype (BZM,, , ).

Determination Clarifications
This species corresponds to Myrmecina sp. E of Aoki and Ito (1997).