Myrmecina gopa

Okido, Ogata, and Hosoishi (2020) - Colonies of this species are unicolonial. Their nests are contiguously rather than uniformly distributed, and conspecific nonnestmates are easily incorporated into alien nests (Tsuji et al., 2001). Ito (1996) reported that this species, which has a specialized myrmecophilous oribatid mite Aribates javensis Aoki, Takaku & Ito (Ito & Takaku, 1994; Aoki et al., 1994), has no queen, but an ergatogyne as a reproductive caste. Ergatogynes distinguish from workers only in width and length of their first gastral tergum. Colonies of this species are polygynous, having 8 ergatogynes on average per colony, and all mated ergatogynes reproduce without aggressive interactions.

Identification
Okido, Ogata, and Hosoishi (2020) - Myrmecina gopa does not belong to any species complex. But M. gopa is similar to Myrmecina dolichothrix on the basis of some characters (see the remarks of M. dolichothrix). Among those species, M. gopa can be distinguished from the remains by having the short pilosity and the anterior clypeal margin with three processes.

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

Nomenclature

 * . Myrmecina gopa Okido, Ogata & Hosoishsi, 2020: 42, fig. 17 (w.) INDONESIA.

Worker
Holotype. TL 2.61, HL 0.61, HW 0.58, CI 95, SL 0.53, SI 92, PW 0.41, ML 0.67. Paratype. TL 2.54-2.90, HL 0.57-0.65, HW 0.54-0.62, CI 91-97, SL 0.50-0.56, SI 88-96, PW 0.37-0.44, ML 0.64-0.75 (25 measured).

Head subrectangular, slightly 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 4-5 small teeth and a small basal tooth; small teeth frequently unclear. Dorsal surface of clypeus slightly concave; median portion of anterior margin projected with three processes; lateral portion simple, lacking sharp ridge in front of antennal insertions. Anterior dorsal surface of labrum with paired denticles very small. Frontal carinae virtually absent, indistinguishable from rugae on dorsum of head. Eyes large and moderately convex, varying in size with maximum diameter 0.08-0.11 mm and 5-6 ommatidia; malar space twice as long as diameter of eye or shorter in profile; distance between occipital margin and posterior margin of eye three times as long as diameter of eye. Antennal scape long, extending beyond posterolateral corner of head; antennal flange developed.

Dorsal outline of mesosoma convex in profile. Pronotum without denticles; anterior portion usually marginate; anterior ventrolateral portion not angulate. Furrow between pronotum and mesoepisternal projection more or less broad. Eumetanotal spine absent. Propodeal spine elongate, 1.5 times as long as broad at base, extending over vertical posteriormost limit of propodeum in profile. Propodeal lobe low. Propodeal spiracle large, situated near posterior margin of propodeum, distance between posterior margin of spiracle and posterior margin of propodeum shorter 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 present at anterior portion, usually bearing acute anterior apex, but varied in shape, sometimes triangular or lobed with a hole. Postpetiole broader than petiole in dorsal view; lateral margin usually straight; anterior portion sharply raised; ventral outline projected with two acute points.

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

Head with straight rugae distinctly; ventrolateral portion usually smooth and shining. Clypeus smooth and shining. Mesosoma with straight rugae distinctly. 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. Dorsal pilosity of petiole slightly longer than that of mesosoma. Petiole without hairs on ventral surface. Postpetiole usually without hairs on ventral surface. Head and mesosoma black, petiole, postpetiole and gaster reddish brown, mandibles, antennae and legs yellowish brown.

Type Material
Holotype worker, INDONESIA: Kebun Raya, Bogor, W. Java, 11. ix. 1996, FI96-375 (F. Ito). Paratypes. numerous workers, ergatogynes and males with same data as holotype; numerous workers, ergatogynes and males with same data as holotype but 17-20. ii. 1993, FI93-157; numerous workers and ergatogynes, and 1 male with same data as holotype but 17-20. ii. 1993, FI93-159; numerous workers, ergatogynes and males with same data as holotype but 17-20. ii. 1993, FI93-162; numerous workers, ergatogynes and males with same data as holotype but 17-20. ii. 1993, FI93-163 (BZM,, ).

Determination Clarifications
This species corresponds to Myrmecina sp. A of Ito (1996), Aoki & Ito (1997), Ito et al. (2001) and Tsuji et al. (2001).