Clearnose Skate: Rostroraja eglanteria

Family: Rajidae

Common name(s)

Clearnose skate.

Identification

A medium-sized skate with a wide kite-shaped disc. Disc width ~1.2 x disc length. Snout moderately long, with an approximately right-angular tip. Snout length ~4.8 x orbit length. Eyes small. Anterior margins of pectoral fins almost straight or weakly undulate. Pectoral apices angular. Disc sparsely covered in large granulations in juveniles, mostly absent in adults. Juveniles have 3-4 orbital thorns and one thorn on each shoulder. Adult males have a small patch of malar (cheek) thorns. Midline thorns continuous from nape to first dorsal fin. Lateral thorn rows occur on tail. Ventral thorn patches present on snout and along anterior disc margin. Pelvic fins large, strongly notched. Anterior pelvic lobe well defined but much shorter than posterior lobe. Tail longer than disc, broad-based, tapering strongly to narrow tip. Lateral skin folds on tail well developed. Dorsal fins high, slightly separated, with narrowly rounded or angular apices. Caudal fin small.

Colour

Dorsum greyish-brownish, brown, or blotchy, with a pattern of thin, dark brown lines and spots positioned transversely and diagonally. Tail usually unmarked or with diffuse brown saddles. Dorsal fins unmarked. Ventrum white and unmarked.

Size

Maximum length 84cm. Length at hatching 13-14cm.

Habitat

Temperate to tropical seas. Demersal on mixed substrates. Occurs inshore, and on the continental shelf to 330m.

Distribution

Western Atlantic. The clearnose skate occurs from the northern Gulf of Mexico and Florida to Massachusetts, USA. Population much sparser south of the Carolinas. Only 62 catch records from the Gulf of Mexico.

Conservation Status

LEAST CONCERN

The Clearnose Skate (Rostroraja eglanteria) is captured as bycatch in commercial otter trawl and scallop dredge fisheries that operate over much of its range. Fisheries landings of this skate are minimal however because it is not large enough to be marketable, and there is no directed fishery. It is likely discarded at sea and at-vessel mortality is low. There are no estimates of population size, but catch-per-unit-effort increased in northeast US fisheries surveys over the period of 1975–2018. Overall, based on this long-term increase in CPUE, its minimal presence in landings, medium size and likely moderately productive life history, and its high survivorship upon being discarded, the population is inferred to be increasing. There is no evidence of population decline and the species is not suspected to be close to reaching the population reduction threshold, and this species is assessed as Least Concern.

Citation

Anderson, B., Kulka, D.W., Herman, K., Pacoureau, N. & Dulvy, N.K. 2020. Rostroraja eglanteria. The IUCN Red List of Threatened Species 2020: e.T161658A124523079. https://dx.doi.org/10.2305/IUCN.UK.2020-3.RLTS.T161658A124523079.en. Downloaded on 27 April 2021.

Reproduction

Oviparous. Females mature at ~5.8yrs.

Diet

Clearnose skates feed on worms, crustaceans and bony fishes.

Behavior

Poorly known. Sometimes enters estuaries.

Reaction to divers

Probably easy to approach but poorly known.

Diving logistics

The clearnose skate is seen fairly regularly by divers in the northern part of its range i.e. from New Jersey to Massachusetts, but they also stray into shallow water further south. For example, there are occasional sightings at the Blue Heron Bridge; a popular estuarine dive site in southern Florida.