Pateobatis jenkinsii

Pateobatis jenkinsii (Annandale, 1909)

Jenkins’ whipray

Fig. 9

Trygon jenkẚnsẚẚ Annandale, 1909: 28; holotype: ZSI F2473/1; type locality: Orissa State, India.

Material examined: No specimen collected, underwater photographs, Socotra Island, Ras Bidou, 14 m depth, 17 April 2019; underwater photograph, Socotra Island, Roosh, 3 m depth, 13 April 2019.

Distinctive characters: maṫeobaṫẚs jenkẚnsẚẚ is characterised by having a rhomboidal disc, its width slightly greater than disc length; tip of snout obtuse, slightly projecting; a narrow, asymmetrical well-defined band of denticles on back; a row of enlarged thorns along midline of disc and tail to the base of spine, a character unique within large whiptail stingrays (denticles band and thorns reduced or absent in young); tail relatively long and slender, without cutaneous fold, tail length 1.1–1.4 times disc width (Last eṫ al. 2016c; Psomadakis eṫ al. 2019).

Colouraṫẚon: Dorsal surface of disc plain uniform greyish, yellowish brown or greenish brown, immature specimens with small dark spots on outer disc margins; tail blackish beyond sting. Ventral surface white (Last eṫ al. 2016c; Psomadakis eṫ al. 2019).

Distribution: Ranging from the inner Gulf of Aden and Socotra Archipelago, possibly to the Gulf, southward to Madagascar and South Africa, eastward to the Philippines and Papua New Guinea. In the Arabian region it is known from the Gulf of Tadjoura (Lips eṫ al. 2016) and Oman (Randall 1995). Eagderi eṫ al. (2019) listed the species from the Gulf, but the record should be confirmed in comparison with the similar mK faẚ (Jordan & Seale, 1906). Almojil eṫ al. (2015) included mK faẚ in their book with occurrence in the Gulf confirmed by a specimen collected from the United Arab Emirates.

Remarks: The photographed individuals match well all characters of maṫeobaṫẚs jenkẚnsẚẚ provided by Last eṫ al. (2016c), particularly showing the characteristic row of prominent thorns along mid-line of disc and tail and the small dark spots on rear margins of disc typical for immature specimens. The species inhabits sandy bottoms of shallow lagoons, bays and seaward reefs, often close to coral reefs, at depths of 3–90 m following Weigmann (2016) whereby the minimum depth is based on a newly photographed individual at Roosh. The present confirmed record from Socotra is based on individuals observed on silty sand bottom close to large rocks with overhangs in Ras Bidou, western part of Socotra Island, at a depth of 14 m, and an individual found under a ledge of a large stone at Roosh, north-eastern part of the island, at a depth of 3 m. Subadults are characterised by having small brown spots on edges of posterior half of disc. This growth stage was described as a distinct species, eK draco Compagno & Heemstra, 1984, but subsequently placed in synonymy with eK jenkẚnsẚẚ (Last & Compagno 1999). maṫeobaṫẚs jenkẚnsẚẚ is included as vulnerable in IUCN Red List Assessments and urgently requires conservation management (Manjaji Matsumoto eṫ al. 2016b). maṫeobaṫẚs faẚ, reported from the Red Sea to the Marquesas Islands, is a similar species, which possibly also occurs off Socotra Archipelago. It might be confused with mK jenkẚnsẚẚ but differs in having only few slightly enlarged thorny denticles mid-centrally on disc and a mid-row of enlarged rounded tubercles at base of tail (Last eṫ al. 2016c; Psomadakis eṫ al. 2019).