Onychotrechus Kirkaldy

Nakthong, La-Au, Vitheepradit, Akekawat & Sites, Robert W., 2014, Key to the species of Eotrechinae (Hemiptera: Heteroptera: Gerridae) of Thailand and review of the fauna of the Phetchabun Mountain Range, Zootaxa 3860 (1), pp. 47-63 : 61

Genus Onychotrechus Kirkaldy

Figs. 5 , 7

This genus was revised by Andersen (1980) and was represented by nine described and one undescribed species distributed from India to Malaysia. Of these, only three occur in Southeast Asia. Moreover, the undescribed species was later discovered to be a variation of O. esakii Andersen , which is a common and widespread species in Southeast Asia. Later, one species from Sri Lanka ( Polhemus & Andersen 1984) and another from India (Zettel & Tran 2007) were described. In Thailand, only one described species has been recorded ( Chen & Zettel 1998). Members of this genus are hygrophilic and found on wet rocks or moss in streams, and some are on the ground away from water but near the aquatic habitat, which is a unique behavior of the genus ( Andersen 1980). One widespread, common species was collected from waterfalls in this study.

Figures

FIGURES 3 – 5. Genera of male Eotrechinae. (3) Amemboa, (4) Eotrechus, (5) Onychotrechus.

FIGURES 6 – 7. Distal leg segments showing pretarsal claws. (6) Eotrechus, (7) Onychotrechus.