An investigation into the taxonomy of Abavorana luctuosa (Peters, 1871) (Anura, Ranidae) and the resurrection of Rana decorata Mocquard, 1890 from Borneo Author Quah, Evan S. H. Institute of Tropical Biodiversity and Sustainable Development, Universiti Malaysia Terengganu, 21030 Kuala Nerus, Terengganu, Malaysia, https: // orcid. org / 0000 - 0002 - 5357 - 1953 & Herpetology Laboratory, Department of Biology, La Sierra University, Riverside, California, USA, https: // orcid. org / 0000 - 0001 - 8422 - 3698 & Lee Kong Chian Natural History Museum, National University of Singapore, 2 Conservatory Drive, 117377 Singapore, https: // orcid. org / 0000 - 0002 - 0638 - 9198 Author Grismer, L. Lee Herpetology Laboratory, Department of Biology, La Sierra University, Riverside, California, USA, https: // orcid. org / 0000 - 0001 - 8422 - 3698 Author Wood Jr., Perry L. https://orcid.org/0000-0003-3767-5274 Department of Biological Sciences & Museum of Natural History, Auburn University, Auburn, Alabama 36849, USA, https: // orcid. org / 0000 - 0003 - 3767 - 5274 Author Lim, Kelvin K. P. Lee Kong Chian Natural History Museum, National University of Singapore, 2 Conservatory Drive, 117377 Singapore, https: // orcid. org / 0000 - 0002 - 0638 - 9198 Author Imbun, Paul Y. Museum of Zoology, Research & Education Division, Sabah Parks, 10626 Kota Kinabalu, Sabah, Malaysia Author Anuar, M. S. Shahrul School of Biological Sciences, Universiti Sains Malaysia, 11800 Minden, Penang, Malaysia, https: // orcid. org / 0000 - 0003 - 0648 - 7318 & Center for Marine and Coastal Studies, Universiti Sains Malaysia, 11800 USM, Pulau Pinang, Malaysia text Vertebrate Zoology 2021 2021-03-11 71 75 99 http://dx.doi.org/10.3897/vz.71.e60921 journal article http://dx.doi.org/10.3897/vz.71.e60921 2625-8498-71-75 1C61F5FE1FA44083B91313FD42157FCA C87DE9A5FDFA5B5FA5603914E35A1446 Abavorana nazgul Quah, Shahrul Anuar, Grismer, Wood, Siti Azizah & Muin 2017 Gunung Jerai Black Stream-Frog Figs 8G-H , 9E-F Rana luctuosa Sukumaran, J. 2005: 38 Holotype. An adult male (USMHC 2231) collected on 9 April 2016 from Gunung Jerai, Kedah, Peninsular Malaysia ( 5°47.719'N ; 100°26.222'E , 948 m in elevation) by Evan S.H. Quah and David Chan. Diagnosis. Abavorana nazgul can be differentiated from its congeners by the following combination of characters: adult males 41.51-44.1 mm SVL and single adult female 52.51 mm; adult males with SW 7.98-8.70 mm, single adult female SW 9.59 mm; adult males with IOD 3.94-4.48 mm, single adult female IOD 4.94 mm; adult males with TD 3.52-4.01 mm, single adult female TD 4.10 mm; adult males with FL 22.20-23.22 mm, single adult female FL 27.80 mm; nuptial pads absent in males; humeral glands in males small (2.4-2.98 mm) (Table 5 ); dorsolateral stripe continuous, orange to yellow in colour; dorsum between dorsolateral stripes black, with or without faint orange or yellow speckles; flanks black, colouration unstratified; distinct cream-colored spots on flanks, dorsal surfaces of limbs, and upper lip; venter grey-brown with prominent light spots on throat and belly, smaller spots on underside of thigh (Fig. 9E-F ; Quah et al. 2017 ). Distribution. Abavorana nazgul is thus far confirmed from the upper elevations of Gunung Jerai, Kedah, Peninsular Malaysia ( Quah et al. 2017 ). Specimens resembling this species have been photographed at Thale Ban National Park, Satun Province in southern Thailand at approximately 500-600m in elevation around wild boar wallows but are only tentatively identified as A. cf. nazgul pending positive evidence (Fig. 8H ). Figure 8. Peninsular Malaysian, Thai and Sumatran Abavorana luctuosa , and A. nazgul ; A: A. luctuosa from Sungai Durian Forest Reserve, Kelantan, Peninsular Malaysia. B: A. luctuosa from Janda Baik, Pahang, Peninsular Malaysia. C: A. luctuosa from Semenyih, Selangor, Peninsular Malaysia. D: A. luctuosa from Fraser's Hill, Pahang, Peninsular Malaysia. E: A. luctuosa from Hala-Bala Wildlife Sanctuary, Thailand. F: A. luctuosa from Sumatra, Indonesia. G: A. nazgul (USMHC 2572) from Gunung Jerai, Kedah, Peninsular Malaysia. H. A. cf. nazgul from Thale Ban National Park, Satun Province, Thailand. (Photographs by Zaharil Dzulkafly [A], Steven Wong [B], Kurt H.P. Guek [C], Evan Quah [D & G], Ian Dugdale [E], Hellen Kurniati [F] & Bunyarit Dechochai [H]). Figure 9. Colour pattern comparison among species of the genus Abavorana ; Dorsum (A,C & E) and venter (B,D & F) in life of A. luctuosa (USMHC 2576) (A & B) from Penang Hill, Penang Island, Malaysia, A. decorata from Maliau Basin, Sabah, East Malaysia, Borneo (C & D) and A. nazgul (USMHC 2233) (E & F) from Gunung Jerai, Kedah, West Malaysia. (Photographs by Evan Quah [A, B, E & F] and Stefan T. Hertwig [C & D]). Figure 10. Distribution map of Abavorana decorata and A. luctuosa in Borneo; Known distribution of Abavorana decorata (red) and A. luctuosa (blue) in Borneo. Star = type locality.