Chesterfield Island stingaree
Encyclopedia
The Chesterfield Island stingaree or Deforge's stingaree (Urolophus deforgesi) is a little-known species
of stingray
in the family
Urolophidae, endemic to the continental slope off the Chesterfield Islands
. Reaching 34 cm (13.4 in) long, it has a rounded, diamond-shaped pectoral fin disc colored plain brown above and pale below, with a short head. There is a narrow, skirt-shaped curtain of skin between its nostrils. Its tail is relatively long and terminates in a leaf-shaped caudal fin; there are no dorsal fin
or lateral skin folds. This species has been listed under Least Concern
by the International Union for Conservation of Nature (IUCN), as there is little fishing activity within its range.
by France and Australia in the 1990s. The species was described by Bernard Séret and Peter Last in a 2003 issue of the scientific journal
Cybium, and named for Institut de Recherche pour le Développement (IRD) scientist Bertrand Richer de Forges. The type specimen is a 32 cm (12.6 in) long adult male collected by the research vessel Coriolis. This species is closely related to the New Caledonian stingaree
(U. neocaledoniensis), and also bears morphological
similarities to the mitotic stingaree (U. mitosis).
, northwest of New Caledonia
. This bottom-dwelling ray inhabits the continental slope over a depth range of 203–330 m (666–1,082.7 ft).
s. There is a narrow, skirt-shaped curtain of skin between the nostrils, with a deeply fringed posterior margin and the posterior corners drawn out into lobes. The mouth is modestly sized and contains 7–8 papillae (nipple-like structures) on the floor, arranged in a "W"; there is also a patch of small papillae on the lower jaw. There are 28–33 upper tooth rows and 27–31 lower tooth rows. The five pairs of gill slit
s are short. The pelvic fins are small and rounded; males have slender, pointed claspers.
The tail is somewhat flattened and measures 77–84% as long as the disc. There is a single dorsally placed, serrated stinging spine around halfway along the tail, and no dorsal fin
or lateral skin folds. The tail terminates in a long, low, leaf-shaped caudal fin. The skin is entirely devoid of dermal denticles. This species is plain yellowish brown above with a dark caudal fin margin, which is more obvious in juveniles. The underside is white to cream, darkening slightly at the fin margins. The largest known specimen is 34 cm (13.4 in) long.
at under 29 cm (11.4 in) long.
, as no commercial
trawl fishing
occurs within its range.
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
of stingray
Myliobatiformes
Myliobatiformes is one of the four orders of batoids, cartilaginous fishes related to sharks. They were formerly included in the order Rajiformes, but more recent phylogenetic studies have shown that the myliobatiforms are a monophyletic group, and that its more derived members evolved their...
in the family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
Urolophidae, endemic to the continental slope off the Chesterfield Islands
Chesterfield Islands
Chesterfield Islands is a french archipelago of New Caledonia located in the Coral Sea, 550 km northwest of Grande Terre the main island of New Caledonia. Chesterfield Islands are a 120 km long and 70 km broad structure composed with 11 islets and many reefs...
. Reaching 34 cm (13.4 in) long, it has a rounded, diamond-shaped pectoral fin disc colored plain brown above and pale below, with a short head. There is a narrow, skirt-shaped curtain of skin between its nostrils. Its tail is relatively long and terminates in a leaf-shaped caudal fin; there are no dorsal fin
Dorsal fin
A dorsal fin is a fin located on the backs of various unrelated marine and freshwater vertebrates, including most fishes, marine mammals , and the ichthyosaurs...
or lateral skin folds. This species has been listed under Least Concern
Least Concern
Least Concern is an IUCN category assigned to extant taxon or lower taxa which have been evaluated but do not qualify for any other category. As such they do not qualify as threatened, Near Threatened, or Conservation Dependent...
by the International Union for Conservation of Nature (IUCN), as there is little fishing activity within its range.
Taxonomy
The first known specimens of the Chesterfield Island stingaree were caught during a series of research cruises undertaken in the Coral SeaCoral Sea
The Coral Sea is a marginal sea off the northeast coast of Australia. It is bounded in the west by the east coast of Queensland, thereby including the Great Barrier Reef, in the east by Vanuatu and by New Caledonia, and in the north approximately by the southern extremity of the Solomon Islands...
by France and Australia in the 1990s. The species was described by Bernard Séret and Peter Last in a 2003 issue of the scientific journal
Scientific journal
In academic publishing, a scientific journal is a periodical publication intended to further the progress of science, usually by reporting new research. There are thousands of scientific journals in publication, and many more have been published at various points in the past...
Cybium, and named for Institut de Recherche pour le Développement (IRD) scientist Bertrand Richer de Forges. The type specimen is a 32 cm (12.6 in) long adult male collected by the research vessel Coriolis. This species is closely related to the New Caledonian stingaree
New Caledonian stingaree
The New Caledonian stingaree is a little-known species of stingray in the family Urolophidae, found off New Caledonia and the adjacent Chesterfield Islands and Norfolk Ridge. This species reaches long and has a rounded, diamond-shaped pectoral fin disc slightly wider than long. There is a...
(U. neocaledoniensis), and also bears morphological
Morphology (biology)
In biology, morphology is a branch of bioscience dealing with the study of the form and structure of organisms and their specific structural features....
similarities to the mitotic stingaree (U. mitosis).
Distribution and habitat
The range of the Chesterfield Island stingaree is limited to the Chesterfield IslandsChesterfield Islands
Chesterfield Islands is a french archipelago of New Caledonia located in the Coral Sea, 550 km northwest of Grande Terre the main island of New Caledonia. Chesterfield Islands are a 120 km long and 70 km broad structure composed with 11 islets and many reefs...
, northwest of New Caledonia
New Caledonia
New Caledonia is a special collectivity of France located in the southwest Pacific Ocean, east of Australia and about from Metropolitan France. The archipelago, part of the Melanesia subregion, includes the main island of Grande Terre, the Loyalty Islands, the Belep archipelago, the Isle of...
. This bottom-dwelling ray inhabits the continental slope over a depth range of 203–330 m (666–1,082.7 ft).
Description
The pectoral fin disc of the Chesterfield Island stingaree is diamond-shaped and 109–122% as wide as long, with broadly rounded outer corners and gently convex leading margins. The snout is fleshy and forms an obtuse angle, with the tip slightly protruding. The eyes are medium-sized and somewhat closely spaced, and immediately followed by teardrop-shaped spiracleSpiracle
Spiracles are openings on the surface of some animals that usually lead to respiratory systems.-Vertebrates:The spiracle is a small hole behind each eye that opens to the mouth in some fishes. In the primitive jawless fish the first gill opening immediately behind the mouth is essentially similar...
s. There is a narrow, skirt-shaped curtain of skin between the nostrils, with a deeply fringed posterior margin and the posterior corners drawn out into lobes. The mouth is modestly sized and contains 7–8 papillae (nipple-like structures) on the floor, arranged in a "W"; there is also a patch of small papillae on the lower jaw. There are 28–33 upper tooth rows and 27–31 lower tooth rows. The five pairs of gill slit
Gill slit
Gill slits are individual openings to gills, i.e., multiple gill arches, which lack a single outer cover. Such gills are characteristic of Cartilaginous fish such as sharks, rays, sawfish, and guitarfish. Most of these have five pairs, but a few species have 6 or 7 pairs...
s are short. The pelvic fins are small and rounded; males have slender, pointed claspers.
The tail is somewhat flattened and measures 77–84% as long as the disc. There is a single dorsally placed, serrated stinging spine around halfway along the tail, and no dorsal fin
Dorsal fin
A dorsal fin is a fin located on the backs of various unrelated marine and freshwater vertebrates, including most fishes, marine mammals , and the ichthyosaurs...
or lateral skin folds. The tail terminates in a long, low, leaf-shaped caudal fin. The skin is entirely devoid of dermal denticles. This species is plain yellowish brown above with a dark caudal fin margin, which is more obvious in juveniles. The underside is white to cream, darkening slightly at the fin margins. The largest known specimen is 34 cm (13.4 in) long.
Biology and ecology
Little is known of the natural history of the Chesterfield Island stingaree. It is presumably aplacental viviparous with a small litter size, as in other members of its family. Newborns measure around 13 cm (5.1 in) long and males reach sexual maturitySexual maturity
Sexual maturity is the age or stage when an organism can reproduce. It is sometimes considered synonymous with adulthood, though the two are distinct...
at under 29 cm (11.4 in) long.
Human interactions
The International Union for Conservation of Nature (IUCN) has listed the Chesterfield Island stingaree under Least ConcernLeast Concern
Least Concern is an IUCN category assigned to extant taxon or lower taxa which have been evaluated but do not qualify for any other category. As such they do not qualify as threatened, Near Threatened, or Conservation Dependent...
, as no commercial
Commercial fishing
Commercial fishing is the activity of catching fish and other seafood for commercial profit, mostly from wild fisheries. It provides a large quantity of food to many countries around the world, but those who practice it as an industry must often pursue fish far into the ocean under adverse conditions...
trawl fishing
Fishery
Generally, a fishery is an entity engaged in raising or harvesting fish which is determined by some authority to be a fishery. According to the FAO, a fishery is typically defined in terms of the "people involved, species or type of fish, area of water or seabed, method of fishing, class of boats,...
occurs within its range.