Genus Chrysapace Crawley, 1924

Chrysapace Crawley, 1924: 380 . Typespecies: Chrysapace jacobsoni Crawley, 1924 (junior secondary homonym in Cerapachys, replaced by Cerapachys crawleyi W. M. Wheeler, 1924), by monotypy.

Diagnosis. This genus can be recognized by a combination of the following characteristics of the worker caste: i) prominent costate sculpture on most of body surface, ii) large eyes, iii) exposed antennal sockets, iv) two spurs on mid and hind tibiae, and v) pretarsal claws with a tooth (BOROWIEC 2016).

Key to Chrysapace species based onthe worker caste. The key to valid species is provided below. Known distribution is shown in the parentheses after species name. Our knowledge on C. jacobsoni is based on its original description (CRAWLEY 1924), WHEELER (1924), and BROWN (1975).

1 Abdominal tergite IV–VI longitudinally costate (except for anterior marginal areas); dorsum of mesosoma transversely arched in most areas. ................................... .......................................... C. jacobsoni Crawley, 1924 (Sumatra, Borneo, Philippines)

– Abdominal tergite IV–VI lacks any costation; dorsum of mesosoma longitudinally costate. ............................ 2

2 Abdominal tergite III with costae which are transversely arched around center of posterior margin in dorsal view (Fig. 5). ....................... C. merimbunensis sp. nov. (Brunei)

– Abdominal tergite III longitudinally costate. ............. 3

3 Costae on vertex at most weakly distorted (Fig. 41); eye and ocelli relatively small (EI + OI ≦ 25). ...................... .................................................. C. sauteri (Forel, 1913) (Taiwan)

– Costae on vertex strongly and coarsely distorted (Figs 42–43); eye and ocelli relatively large (EI + OI ≧ 29). ........................ C. costatus (Bharti & Wachkoo, 2013) (northern India, Yunnan, Guangxi)