Rhinobatos ranongensis Last & Séret & Naylor 2019, sp. nov.

• Main Authors: Last, Peter R., Séret, Bernard, Naylor, Gavin J. P.
• Format: Other/Unknown Material
• Language: unknown
• Published: 2019
• Subjects: Biodiversity; Taxonomy; Animalia; Chordata; Elasmobranchii; Rajiformes; Rhinobatidae; Rhinobatos; Rhinobatos ranongensis; Fridtjof; Fridtjof Nansen
• Online Access: https://zenodo.org/record/5926021; https://doi.org/10.5281/zenodo.5926021

Rhinobatos ranongensis sp. nov. Ranong Guitarfish (Figs 8–14; Table 2) urn:lsid:zoobank.org:act: B80CB45D-2AC1-4BF3-8160-DA2D88BA17C9 Holotype. CSIRO H 7861-02 (GN 17091), adult male 645 mm TL, Andaman Sea, W of Maliwun, Myanmar, 10°20.97 N, 97°46.14 E, bottom trawl, 69 m depth, RV Dr Fridtjof Nansen station 173, specimen 754, collected P. Psomadakis, 25 May 2015. Paratypes. 4 specimens. ANSP 171546, adult male 637 mm TL, Ranong fish landing, collected from Andaman Sea, off Myanmar or western Thailand, ~ 30–40 m, 1994. H 8403-01 (formerly SA005), juvenile male 494 mm TL, Ranong fish landing, collected S. Arunrugstichai, 17 Jul 2014; H 8404-01 (formerly SA043), juvenile male 425 mm TL, H 8404-02 (formerly SA045), female 392 mm TL, Ranong fish landing, collected S. Arunrugstichai, 22 Jan 2015. Other material. 5 specimens (not retained). GN 16774, female 511 mm TL, 16775, immature male 503 mm TL (tissues only), Ranong fish landing, collected Andaman Sea, off Myanmar or western Thailand, W. White, 2014; GN 17066 (tissue and image), female 690 mm TL, Bay of Bengal, Myanmar, RV Dr Fridtjof Nansen, station 126, collected P. Psomadakis; GN 17070 (tissue and image), female 530 mm TL, Bay of Bengal, Myanmar, RV Dr Fridtjof Nansen, station 132, collected P. Psomadakis; GN 17105, tissue, 350 mm TL, Bay of Bengal, Myanmar, RV Dr Fridtjof Nansen, station 125, collected P. Psomadakis. Diagnosis. A medium-sized species of the genus Rhinobatos (attaining at least 645 mm TL) distinguished by the following combination of characters in adult male: disc wedge-shaped, relatively narrow, width 31–33% TL, length 1.3–1.4 times width; snout moderately elongate, length 3.0–3.2 times interspiracular distance, 4.1–4.4 times interorbital width; orbit and spiracular openings small, orbit diameter ~1.5 times spiracle length; nostrils weakly oblique, their length 1.3–1.6 times internarial distance; mouth narrow, 5.4–6.0% TL; preoral length 6.3–6.9 times internarial distance; posterior nasal flaps broad; two spiracular folds, outermost fold ...