Myrmecina salmahae

This species is known only from the highland of Sumatra. It was collected from leaf litter in the primary highland forests. Other information about the biology of this species is absent.

Identification
Myrmecina salmahae is easily separated from the other 16 Myrmecina species recorded from Sumatra by a combination of the following characters of the worker:
 * relatively large species (HL 1.73−1.81 mm, HW 1.94−2.02 mm, WL 2.18−2.36 mm)
 * posterior margin of head slightly concave
 * mesosoma in lateral view short and stout, as long as height, with dorsal outline convex
 * eumetanotal spine present and small
 * propodeal spines in lateral view elongate-triangular, as long as broad and pointed apically
 * propodeal declivity with posterodorsal angle less than 90°
 * subpetiolar process absent
 * head dorsally with coarse longitudinal rugae
 * mesosoma, petiole and postpetiole with coarse irregular longitudinal rugae

Myrmecina salmahae can not be assigned to any species group which is proposed by Okido et al. (2020). It keyed out as [[Myrmecina aspera] at the couplet 19 of the key provided by Okido et al. (2020), but is distinguished from the latter by a combination of the following characters:
 * masticatory margin of mandible bent at midlength (vs. straight in the latter)
 * eye large with EL 0.27−0.28 mm and 34−45 ommatidia (vs. small with EL 0.14 mm and 7 ommatidia in the latter)
 * mesosoma in lateral view short and stout, as long as height (vs. longer than height in the latter)
 * mesosoma with coarse irregular longitudinal rugae (vs. coarse longitudinal rugae in the latter).

It is also morphologically similar to Myrmecina boltoni and Myrmecina padangensis, on the basis of the following characteristics:
 * head and mesosoma with coarse longitudinal rugae
 * antennal scape relatively short
 * eumetanotal spine present
 * propodeal spine relatively short
 * petiole longer than postpetiole in lateral view
 * petiole without subpetiolar process.

However, it is distinguishable from the latter two by the following characteristics:
 * posterior margin oh head slightly concave (vs. slightly concave in M. boltoni; almost straight in M. padangensis)
 * mesosoma in lateral view short and stout, as long as height (vs. longer than height in the latter two)
 * eye large with EL 0.27−0.28 mm and 34−45 ommatidia (vs. 0.11−0.16 mm and 5−10 ommatidia in M. boltoni; 0.14 mm and 8 ommatidia in M. padangensis)
 * propodeal spine relatively small, as long as broad at base and pointing posteriad (vs. longer than broad in the latter two)
 * mesosoma in dorsal view with coarse and irregular rugae (vs. longitudinal rugae in M. boltoni; irregular rugae in M. padangensis)
 * forecoxa smooth and shiny (vs. sculptured in M. boltoni; smooth and shiny in M. padangensis)

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

Nomenclature

 * . Myrmecina salmahae Satria & Eguchi, 2022: 3, figs. 1, 2 (w.) INDONESIA (Sumatra).

Type Material

 * Holotype: worker (individual code: SEMUT22iv2022B), Indonesia: West Sumatra, 50 Kota District, Situjuah Limo Nagari, Situjuah Gadang, Sago Moutain, 3°49'521" N, 97°31'198" E, ca. 2000 m alt., 13.I 2022, Nur Aqsha leg. (MZB).
 * Paratypes: workers (n=6, individual code: SEMUT13i2022, SEMUT22iv2022A, SEMUT22iv2022C, SEMUT22iv2022D, SEMUT22iv2022E, SEMUT22iv2022F), same data as holotype (RSC).