Ranatra thai Lansbury, 1972

Tran, A. D. & Zettel, H., 2021, Taxonomy of the Ranatra biroi group sensu Lansbury, 1972 (Nepomorpha: Nepidae), with descriptions of two new species, Raffles Bulletin of Zoology 69, pp. 507-521 : 518-519

Ranatra thai Lansbury, 1972

Ranatra longipes thai Lansbury, 1972: 334 (type locality: Chon Buri, Thailand); Tran & Polhemus, 2012: 102, 104 (elevated to species rank).

Material examined. THAILAND: 1 male, Narathiwat Prov., Ban Sac, coll. H. K. Lua, 23 October 1998, LHK0402 ( ZRC) ; 2 males, Narathiwat Prov., Sg. Padi, coll. H. K. Lua, 23 October 1998, LHK0403 ( ZRC) ; 2 males, Nakhon Rachasima Prov. , outlet Lam Takong reservoir, coll. H. H. Tan, 16 January 1997, THH9716 ( ZRC) ; 2 males, Mekong river basin, Huang River tributary, stream on route 2103, 2 km S. of Dan Sai , 17°16′0.9″N, 101°08′29.2″E, coll. S. H. Tan & N. Sivasothi, 21 March 1996, TG11 ( ZRC) ; 2 males, 4 females, Mae Hong Son Prov., 17 road-km N Mae Hong Son, Mok Cham Pae, near Fish Cave , coll. H. Zettel, 11 November 1995 (12a, 12b) ( NHMW) ; 1 female, Chiang Mai Prov., Chiang Dao, Ban Yang Thung Pong , c. 500 m a.s.l., coll. H. Zettel, 8 November 1995 (10) ( NHMW) ; 2 females, Khon Kaen Prov., Khon Kaen University, Plastic Pond, coll. H. Zettel, 26 November 1995 (28) ( NHMW) ; 1 male, Chayaphum Prov. , Tat Ton NP, Tat Bong, coll. H. Zettel, 27 November 1995 (29) ( NHMW) ; 1 male, 1 female, Chayaphum Prov. , Tat Ton NP, Tat Ton, coll. H. Zettel, 27 November 1995 (30) ( NHMW) ; 1 male, Chonburi, Ko Chang , 12°02′N, 102°18′E, coll. F. Seyfert, 26 October–3 November 2002 (2) ( NHMW) ; 1 male, Sakhon Nakhon, 11 km NE Khan Poon, Huai Ya , coll. W. D. Shepard, 5 March 1994 ( NHMW) ; 1 male, 1 female, Krabi, Ao Nang, coll. M. Madl, 22 November 1991 (2, 3) ( NHMW) ; 8 males, 6 females, Nakhon Ratchasima Prov., Lam Takhong , near Khao Yai NP, stream, 380 m a.s.l., coll. H. Zettel, 8 January 2009 (50) ( NHMW) .

LAOS: 1 female, Champasak Province, Bolaven Plateau, Paksong , 1,250 m a.s.l., coll. P. Schwendinger, 27 December 1996 ( NHMW) .

CAMBODIA: 3 males, 2 females, Kampot Province, O’saray stream, 10°41′29.3″N, 104°02′48.8″E, coll. CBC team, 4 March 2019, CA0116.A4 ( RUPP, NHMW) ; 1 male, 1 female, Takeo Province, Boeng Cheung Loung Lake , 11°21′08.1″N, 104°56′27.3″E, coll. RUPP team, 9 March 2019, CA0118, HN ( RUPP) .

MALAYSIA – West : – Perak : 1 male ( ZRC.6.18857), Perak, 2 km after Raban before 286 km to K. Bahru, 5°2′41.2″N, 100°57′13.1″E, coll. H. H. Tan, 19 November 1995, THH9591. – Kelantan : 1 male, Kelantan, Sungei Kemia Hulu Besut, 6 km from Kampong Keruah on road to hydroelectric station, coll. P. Ng et al., 20 March 1992, LHK184 ( ZRC) ; 3 females, Kelantan, tributary of Sungei Hulu Besut, immediately after Kampong Keruah on road to hydroelectric station, coll. H. K. Lua, 20 March 1992, LHK183d ( ZRC) . – Trengganu : 1 male, 1 female, Trengganu, stream at about km 6 on road from Kuala Brang to Kuala Trengganu, coll. P. Ng et al., 19 March 1992, LHK180 ( ZRC) ; 2 males, Trengganu, coll. P. K. L. Ng et al., 18–19 March 1992 ( ZRC) ; 1 male, 2 females, 1 nymph, Trengganu, Rantau Abang, coll. B. Tan & G. Sumita, 16 May 1995, TG04 ( ZRC) ; 1 male, 1 female, Trengganu, north of Ayer Puteh , about 121 km on road from Kuantan to Kuala Trengganu, coll. P. Ng et al., 19 March 1992, LHK181 ( ZRC) ; 5 males, 3 females, Trengganu, Rantau Abang, coll. H. H. Tan, 15 May 1995, THH9518 ( ZRC) ; 1 male, 94 km from K. Trengganu to Kota Bahru , 5°32′38.5″N, 102°43′43.9″E, coll. P. K. L. Ng et al., 19 March 1992 ( ZRC) ; 1 male, Trengganu, north of Rantau Abang , swamp at km 56 on road from Kuala Trengganu to Kuantan, coll. P. Ng et al., 18 March 1992, LHK177 ( ZRC) ; 62 ex. ( ZRC.6.22228), pool at km 94 on road from Kuala Terengganu to Kota Bahru, south of Jerteh , 5°32′38.5″N, 102°43′43.9″E, water temp. 26°C, pH 6.7, coll. H. K. Lua, 19 March 1992. – Selangor : 1 male, Selangor, lake near Templer Park, coll. C. M. Yang, 15 November 1995, YCM77 ( ZRC) ; 1 male, 1 female, Selangor, 0.2 km from 45 km Tg. Malim – Sg. Besar Rd, coll. P. K. L. Ng et al., 18 September 1992 ( ZRC) . – Johor: 2 males, Sg. Selangi, coll. P. Ng et al., 22 April 1992 ( ZRC) .

Diagnosis. Body length: males 21.0–24.0, females 22.0–26.5; siphon length ca. 0.8–1.0× body length; lorum slightly lower than clypeus; vertex higher than eye, with low conical tubercle; eye width ca. 1.2× interocular width; space between middle coxae about 0.6× space between hind coxae; posterior margin of metasternum convex; hind femur, when folded back parallel to body, clearly surpassing apex of operculum (in males) or nearly reaching apex of operculum (in females); paramere slender, apical hook slender, strongly recurved, inner margin of hook without incipient elevation, tip of hook of paramere slightly expanded and rounded.

Distribution. Thailand, Vietnam, Peninsular Malaysia, Cambodia ( Lansbury, 1972; Tran & Polhemus, 2012;

Polhemus & Polhemus, 2013; Tran & Nguyen, 2016; Zettel et al., 2017).