Octotemnus palawanus Chûjô, 1966

Fig. 4A–D

Octotemnus palawanus Chûjô, 1966: 531 (original description).

Comments. From the Province of Palawan, Philippines. This species was described based on two specimens (a holotype and a paratype) and perfectly fits the limits of the genus Octotemnus: 8-segmented antennae, short prosternum and incomplete, acute prosternal process, subconical procoxae projected beyond the level of the prosternum, all tibiae spinose at the outer edge at least at the apical one-third (Kawanabe 2002; Lawrence 2016). Male Octotemnus lack anterocephalic and pronotal modifications but have a sex patch at the first abdominal ventrite covered by a triangular flap. Additionally, males of some species have projected mandibles, usually asymmetrical, and the frons may have a deep impression extending well behind the eyes and delimited posteriorly by a dorsal, transverse vertexal ridge or paired vertexal tubercles (Lawrence 2016). The holotype seems to be a female due to the lack of a sex patch and triangular flap cover at the first abdominal ventrite. It is similar to females of other species in the genus. We chose to maintain it as a valid species until a male is found and compared with males of other species in the genus. Octotemnus encompasses 26 described species and several undescribed ones (Lawrence 2016). The genus occurs in the Nearctic region, Palaearctic region, Australian region, Indo-Chinese and Indian subregions (Oriental region), Indo-Malayan transition zone, and Chinese transition zone.