Ranatra biroi, Lundblad, 1933

Tran, A. D. & Zettel, H., 2021, Taxonomic review of the Ranatra gracilis group sensu Lansbury, 1972 (Nepomorpha: Nepidae), with descriptions of four new species, Raffles Bulletin of Zoology 69, pp. 45-70 : 48

Ranatra biroi group sensu Lansbury, 1972

Diagnosis. Smaller species, body length: males 19–27, females 21–29; siphon moderate to long, ratio of siphon length: body length around 0.6–1.05; vertex in lateral view higher than eye, evenly round, without or with very low tubercle; ratio of eye width: interocular width 0.9–1.3; ratio of anterior pronotal length: posterior pronotal length 1.3–1.8; fore femur slender, flexor side with two teeth nearer to distal end, larger one proximal to smaller one, pre-apical teeth absent; metasternum with posterior margin usually convex (sometimes straight or slightly emarginated); operculum of female at most reaching apex of connexivum.

Species included. Ranatra longipes Stål, 1861 , R. biroi Lundblad, 1933 , R. digitata Hafiz & Pradhan, 1949 , R. natunaensis Lansbury, 1972 , R. longipes celebensis Lansbury, 1972 , R. thai Lansbury, 1972 , R. flagellata Lansbury, 1972 , R. libera Zettel, 1999 , R. incisa Chen, Nieser & Ho, 2004 , R. recta Chen, Nieser & Ho, 2004 , R. rafflesi Tran & D. Polhemus, 2012 , R. nieseri Tran & Nguyen, 2016 , R. cardamomensis Zettel, Phauk, Kheam & Freitag, 2017 , and at least two undescribed species (Tran & Zettel, in prep.).