Ranatra parmata Mayr, 1865: 446 (type locality: Java). — Lansbury, 1972: 298–299 (redescription). — D. Polhemus & J. Polhemus, 2013: 33–34 (diagnosis, distribution records).
Type material examined. Holotype (female, NHMW), “Novara Exp / Jawa.” (hand-writing label, also with labels showing it was det. by Mayr and det. by Lansbury).
Additional material examined. MYANMAR: 1 female (NHMW), Sagaing Division, Alaungdaw Katthapa National Park, Pagoda Stream, 400 m a.s.l., 22°18′33.6″N, 94°27′40.74″E, coll. D. Boukal et al., 6 May 2003.
THAILAND: 1 male (ZRC), Narathiwat Province, Nam Tok Sipo, downstream, coll. H.H. Tan et al., 24 October 1998, THH9891/LHK407; 1 female (ZRC), Phuket, Nam Tok Kathun, coll. P.K.L. Ng & H.H. Tan, 8 April 1999, THH9917; 1 male, 2 females (NHMW), Sakhon Nakhon Province, Phu Pan N.P., 480–520 m a.s.l., coll. P. Schwendinger, 7–8 December 1995; 2 females (NHMW), Phetchabun Province, 36 km SE Sila, N Ban Nam Nao, Ban Pala Yai, coll. H. Zettel, 25 November 1995; 1 female (NHMW), Phrae Province, 50 km NE Phrae, Huai Kaet, Kaet river, coll. H. Zettel, 17–18 November 1995; 1 male (NHMW), Chiang Mai Province, Chiang Dao, Ban Yang Thung Pong, 500 m a.s.l., coll. H. Zettel, 8 November 1995; 3 males, 1 female (NHMW), Chonburi, Ko Chang, 12°02′N, 102°18′E, coll. F. Seyfert, 26 October–3 November 2002; 4 males, 2 females (NHMW), Khon Kaen Province, Nam Phong N.P., Huai Khae, stream, 250 m a.s.l., coll. H. Zettel & N. Tubtim, 9 January 2009; 1 male (NHMW), Khon Kaen Province, Phu Wiang N.P., Huai Bong, stream, pools, 260 m a.s.l., coll. H. Zettel & N. Tubtim, 11 January 2009; 1 male (NHMW), Khon Kaen Province, Phu Wiang N.P., Tad Fa Waterfall, stream, 540 m a.s.l., coll. H. Zettel & N. Tubtim, 11 January 2009.
MALAYSIA (West): Kedah: 1 male, 1 female (NHMW), Central Langkawi, Air Tejun, near Kampung Buku, small stream, coll. H. Zettel, 22 November 2006 [published in Zettel & Tran, 2009]. Perlis: 1 male (ZRC), Perlis, Kg. Wang Kelian, Sg. Burma, coll. H.K. Lua, 20 December 2000, LHK0439. Selangor: 1 male, 1 female (ZRC), Selangor, Ulu Yam, in stream, coll. T.M. Leong & G. Lim, 20 September 2002; 2 males, 1 female, 1 nymph (ZRC), Selangor, Ulu Gombak, upland pond nr. send bridge, coll. C.M. Yang et al., 16 November 1995, YCM87; 1 male (ZRC), Selangor, Sg. Gombak tributary, Ulu Gombak, coll. H.K. Lua et al., 5 May 1996, LHK0303; 1 male (ZRC), Selangor, Ulu Gombak, coll. H.K. Lua et al., 6 May 1996, LHK0304.
MALAYSIA (East): Sarawak: 1 male, 1 female (ZRC), Sarawak, Ulu Katibas, coll. Y.Y. Goh, 14 November 1997, GYY027; 3 males, 3 females (ZRC), Sarawak, Sg. Engkabang?, coll. Y.Y. Goh, 17 & 19 November 1997, GYY034; 1 male (ZRC), Sarawak, Sg. Menyarin, coll. Y.Y. Goh, 15 November 1997, GYY028; 1 male (NHMW), ca 40 km SE Kapit, Rumah Ugap Ng, marating bene Kapit Sut, coll. J. Kodada, 3 April 1994; 1 female (NHMW), Kelabit Highlands, 5 km E Bareo, Pa Ukat, c. 1,000 m a.s.l., river, coll. M. Jäch, 1 March 1993. Sabah: 2 males (ZRC), Danum, coll. H.H. Tan, 2 October 1996, THH96123; 1 female (ZRC), Maliau Basin, Heath forest stream, coll. T.B. Lim & K.L. Yeo, 22 May 1996; 1 male (ZRC), Sandakan, Sepilok, Sepilok-Kabili Forest Reserve, Rainforest Discovery Centre, Sungei “Kingfisher” cascade, coll. H.H. Tan, 14 May 2019, THH19-19.
INDONESIA: East Kalimantan: 2 males (ZRC), Mahakam basin, Sg. Lorni, coll. H.H. Tan, 24 March 2000, THH0016; 1 female (ZRC), Mahakam basin, feeder to Sg. Hajuq, coll. H.H. Tan, 29 March 2000, THH0022; 1 male (ZRC), Kayan basin, Sg. I’sau, coll. H.H. Tan, 26 November 1999, THH99102; 1 female (ZRC), Kalimantan Timur, Makaham subdistrict, Sg. Lomi and feeder streams, coll. H.H. Tan, 22 March 2000, THH0011. Nias: 1 female (NHMW), South Nias, Lahusa, Gomo, 0–300 m a.s.l., coll. M. Jäch, 9–11 February 1990. Java: 1 female (NHMW), Badang, [18]96, Cons. Schild. Bali: 2 females (NHMW), Baturiti, coll. M. Jäch, 1 February 1988. Lombok: 1 female (NHMW), Pemenang, coll. M. Jäch, 19 February 1988.
Diagnosis. Body length: males 30–33, females 34–37; ratio of siphon length: body length ca. 0.3–0.35; lorum lower than clypeus and without nodule dorsally; ratio of eye width: interocular width ca. 0.7; posterior width of pronotum ca. 1.25× anterior width; pronotal length ca. 1.7× fore coxa length; hemelytra reaching posterior margin of abdominal tergum VI; posterior margin of metasternum emarginated, with very narrow sublateral grooves, sometimes indistinct; fore femur on flexor side with a median tooth and a median carina, without pre-apical tooth; hind femur, when folded back parallel to body reaching about mid-length of abdominal sternum VI (in both sexes); paramere: ventral side before apical hook with large process bearing pointed tip nearly touching apical hook, hook relatively short with pointed tip.
Distribution. Thailand, Laos, Vietnam, China (Hainan), Andaman Islands, Langkawi Island, Peninsular Malaysia, Borneo (Sabah, East Kalimantan), Nias, Sumatra, Java, Lombok, Sumbawa, Sumba (Lansbury, 1972; J. Polhemus & Starmühlner, 1990; Zettel & Tran, 2009; D. Polhemus & J. Polhemus, 2013; Tran & Nguyen, 2016; Tran & Poggi, 2019). First records for Sarawak (Borneo) and Bali.