Chrysapace merimbunensis

This species is only known from the type locality, Tasek Merimbun (Brunei, Tutong).

Identification
In the worker, cranium subtrapezoidal in fullface view; dorsum of mesosoma longitudinally costate; abdominal tergite III with costae which are transversely arched around center of posterior margin in dorsal view; abdominal sternite III longitudinally costate; cinctus of abdominal segment IV smooth without any costae; abdominal tergite and sternites IV smooth with sparse hair-bearing foveae.

Chrysapace merimbunensis is relatively similar to Chrysapace sauteri and its sibling species Chrysapace costatus by sharing the following characteristics of the worker:
 * dorsum of mesosoma, petiolar tergite, and abdominal sternite III longitudinally costate
 * abdominal tergite IV–VI lacks any costation

However, the worker of the former is easily distinguished from those of the latter two species by subtrapezoidal shape of cranium in full-face view, non-costate posterodorsal face of helcium, abdominal tergite III with costae which are transversely arched around center of posterior margin in dorsal view, and non-costate cinctus of abdominal segment IV.

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

Castes
The queen of C. merimbunensis is currently unknown.

Nomenclature

 * . Chrysapace merimbunensis Yamada & Eguchi, in Yamada, Lin & Eguchi, 2019: 469, figs. 1-19 (w.m.) BORNEO (Brunei).
 * Type-material: holotype worker, 1 paratype worker, 3 paratype males.
 * Type-locality: Brunei: Tasek Merimbun, Tutong, 17.viii.1999, Eg99-BOR-590 (K. Eguchi).
 * Type-depositories: MBSB (holotype); MBSB, MHNG (paratypes).
 * Distribution: Brunei.

References based on Global Ant Biodiversity Informatics

 * Yamada A., C. C. Lin, and K. Eguchi. 2019. Taxonomic notes on the rare ant genus Chrysapace with description of a new species from Brunei (Hymenoptera: Formicidae: Dorylinae). Acta Entomologica Musei Nationalis Pragae 59: 467-480.