Key to the species of Eotrechinae (Hemiptera: Heteroptera: Gerridae) of Thailand and review of the fauna of the Phetchabun Mountain Range Author Nakthong, La-Au Author Vitheepradit, Akekawat Author Sites, Robert W. text Zootaxa 2014 3860 1 47 63 journal article 10.11646/zootaxa.3860.1.2 a26eaf5f-4eba-45ad-8806-dd7288d78493 1175-5326 287060 B9713C6D-BC3B-4EF2-8495-8BDCD535A80D Amemboa (Amemboa) aquafrigida Zettel and Chen Figs. 8 , 22 Amemboa (Amemboa) aquafrigida Zettel and Chen 1997 : Ann. Hist.-Natur. Mus. Nat. Hung. 94−96. Diagnosis. Males of A. aquafrigida have a proctiger with two pairs of caudally directed projections and a round tip ( Fig. 22 ). Further, the male profemur has three distinct hair patches ( Fig. 8 ), whereas A. javanica Lundblad has a single hair patch and A. brevifasciata , A. cristata , and A. riparia each have two hair patches. Males of A. aquafrigida have the proximal hair patch smaller than the other patches, whereas in A. speciosa it is more than twice as large as the other patches. Discussion. Amemboa aquafrigida is known only from Thailand and has been recorded from Nam Nao NP in Phetchabun and Chaiyaphum provinces ( Zettel & Chen 1997 , Chen et al. 2006 ). In this study, this species was collected from rock pools and margins of streams in Nam Nao NP and Na Haew NP. Thus, this species appears to be endemic to the upper part of the Phetchabun Mountain Range. This species occurred synoptically with A. velaris in the stream behind the visitor center in Nam Nao NP and with A. riparia in a rock pool above Tahd Heuang International Waterfall in Na Haew NP. Material examined. THAILAND : Chaiyaphum Province : Nam Nao NP, Heuy Prom Laeng, 16°38'N 101°34'E , 802 m , 3-V-2004 , A. Vitheepradit, L-659 (5 winged males, 1 winged female, 1 wingless female); same locality, 2-II-2011 , KU team C-23 (4 winged males, 16 wingless males, 7 wingless females); same locality, 20-XII- 2012 , KU team, C-239 (2 wingless males, 2 wingless females); Phetchabun Province : Nam Nao NP, stream behind visitor center, 16°44’N 101°34'E , 820 m , 9-III-2002 , A. Vitheepradit, L-275 (4 winged males, 1 winged female); same locality, 3-V-2004 , A. Vitheepradit, L-658 (5 winged males, 5 winged females); Nam Nao NP, Sum Ma Cow, 16°41'N 101°40'E , 562 m , 20-XII-2012 , KU team, C-238 (15 wingless males, 1 wingless female).