Elasmobranchi (squali e razze) (sharks and rays) >
Rhinopristiformes (Shovelnose rays) >
Rhinobatidae (Guitarfishes)
Etymology: Rhinobatos: Greek, rhinos = nose + Greek, batis, -idos = a ray (Raja sp.) (Ref. 45335); ranongensis: Named for the Ranong fish landing in western Thailand, where the first specimen was collected 25 years ago, and subsequently most of the types.
Ambiente: milieu / zona climatica / distribuzione batimetrica / gamma di distribuzione
Ecologia
marino demersale; distribuzione batimetrica 30 - 69 m (Ref. 123963). Tropical
Eastern Indian Ocean: Andaman Sea, Myanmar and western Thailand.
Dimensione / Peso / Età
Maturità: Lm ?  range ? - ? cm
Max length : 64.5 cm TL maschio/sesso non determinato; (Ref. 123963); 51.1 cm TL (female)
Breve descrizione
Chiavi di identificazione | Morfologia | Morfometria
This medium-sized species is distinguished by the following set of characters in adult male: disc is wedge-shaped and relatively narrow, its width 31-33% TL, length 1.3-1.4 times width; snout moderately elongate, its length 3.0–3.2 times interspiracular distance, 4.1-4.4 times interorbital width; orbit and spiracular openings are small, orbit diameter ~1.5 times spiracle length; nostrils weakly oblique, 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 are broad; spiracular folds 2, the outermost fold slightly taller than inner fold; ridges of rostral cartilage are almost parallel, converging anteriorly but not constricted medially; anterior cartilage is broadly sickle shaped, truncate posteriorly; gill slits and their interspaces are narrow, distance between fifth gill slits 3.0-3.2 times in ventral head length; prebranchial sensory pore system distinct, extending to just behind margin of first gill slit; postscapular sensory canal indistinct, deeply embedded, not forming shallow groove; thorn patches present on supraorbit and scapular region, and row along dorsal midline rudimentary, inconspicuous; denticles on dorsal fins are densest anteriorly, present but more sparse posteriorly; dorsal fins are small, height of first 5.4-6.2% TL; pelvic-fin inner margin subequal to its base length; interdorsal distance 2.9-3.3 times first dorsal-fin base; dorsal caudal margin 2.0-2.4 times the preventral margin; upper jaw with 68-82 tooth rows; snout angle 59-64°; pectoral radials 64-68; post-synarcual centra 172-176; nasal lamellae 47-48. Colouration: dorsal fins brownish anteriorly, dusky posteriorly; dorsal disc of adults largely uniformly brownish, no spots or obvious blotches; no large, black, teardrop marking on undersurface of snout (Ref. 123963)
Cross section: flattened.
Caught individuals: males at 49.4 and 50.3 cm TL were immature and the largest female (51.1 cm TL) was most probably at late adolescent or early mature stage of development (Ref. 123963).
Ciclo vitale e comportamento di accoppiamento
Maturità | Riproduzione | Deposizione | Uova | Fecondità | Larve
Last, P.R., B. Séret and G.J.P. Naylor, 2019. Description of Rhinobatos ranongensis sp. nov.(Rhinopristiformes: Rhinobatidae) from the Andaman Sea and Bay of Bengal with a review of its northern Indian Ocean congeners. Zootaxa 4576(2):257-287. (Ref. 123963)
Stato della Lista Rossa IUCN (Ref. 130435: Version 2025-2 (Global))
Minaccia per l'uomo
Harmless
Usi umani
Strumenti
Rapporti speciali
Scarica XML
Fonti Internet
Stime basate su modelli
Indice di diversità filogenetica (Fonte Biblio. 82804) |
PD50 = 0.5000 [Uniqueness, from 0.5 = low to 2.0 = high]. |
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Bayesian length-weight
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a=0.00302 (0.00155 - 0.00589), b=3.13 (2.96 - 3.30), in cm total length, based on LWR estimates for this (Sub)family-body shape (Ref. 93245). |
Livello trofico (Fonte Biblio. 69278) |
3.7 ±0.4 se; based on size and trophs of closest relatives |
Resilienza (Fonte Biblio. 120179) |
Basso, tempo minimo di raddoppiamento della popolazione 4.5 - 14 anni (Preliminary low fecundity). |
Vulnerabilità della pesca (Ref. 59153) |
Moderate vulnerability (35 of 100). 🛈 |