The spotted stingaree (''Urolophus gigas'') is an uncommon

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

of stingray in the

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

Urolophidae The Urolophidae are a family of rays in the order Myliobatiformes, commonly known as stingarees or round stingrays. This family formerly included the genera '' Urobatis'' and '' Urotrygon'' of the Americas, which are presently recognized as formi ...

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found else ...

to shallow waters along the coast of southern Australia. It favors rocky

reef A reef is a ridge or shoal of rock, coral or similar relatively stable material, lying beneath the surface of a natural body of water. Many reefs result from natural, abiotic processes— deposition of sand, wave erosion planing down rock o ...

s and

seagrass Seagrasses are the only flowering plants which grow in marine environments. There are about 60 species of fully marine seagrasses which belong to four families (Posidoniaceae, Zosteraceae, Hydrocharitaceae and Cymodoceaceae), all in the or ...

beds. This species can be readily identified by its nearly circular, dark-colored

pectoral fin Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They are covered with skin and joined together either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as ...

disc, adorned with a complex pattern of white or cream spots. Its eastern and western forms differ slightly in coloration and have been regarded as separate species. There is a skirt-shaped curtain of skin between its nostrils. Its tail is fairly thick and terminates in a short leaf-shaped

caudal fin Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They are covered with skin and joined together either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as ...

; a relatively large

dorsal fin A dorsal fin is a fin located on the back of most marine and freshwater vertebrates within various taxa of the animal kingdom. Many species of animals possessing dorsal fins are not particularly closely related to each other, though through c ...

is present just in front of the stinging spine. Rather reclusive, at least during the day, the spotted stingaree preys largely on

crustacean Crustaceans (Crustacea, ) form a large, diverse arthropod taxon which includes such animals as decapods, seed shrimp, branchiopods, fish lice, krill, remipedes, isopods, barnacles, copepods, amphipods and mantis shrimp. The crustacean group can ...

s. It is

aplacental viviparous Ovoviviparity, ovovivipary, ovivipary, or aplacental viviparity is a term used as a "bridging" form of reproduction between egg-laying oviparous and live-bearing viviparous reproduction. Ovoviviparous animals possess embryos that develop ins ...

: female bear litters of up to 13 pups and supply them with histotroph ("

uterine The uterus (from Latin ''uterus'', plural ''uteri'') or womb () is the organ in the reproductive system of most female mammals, including humans that accommodates the embryonic and fetal development of one or more embryos until birth. The ...

milk") during gestation. Relatively inoffensive towards humans, the

International Union for Conservation of Nature The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of nat ...

(IUCN) has listed this species under

Least Concern A least-concern species is a species that has been categorized by the International Union for Conservation of Nature (IUCN) as evaluated as not being a focus of species conservation because the specific species is still plentiful in the wild. T ...

, citing the overall low level of fishing activity across its range. Furthermore, it is sheltered from commercial

fishing gear Fishing tackle is the equipment used by anglers when fishing. Almost any equipment or gear used in fishing can be called fishing tackle, examples being hooks, lines, baits/ lures, rods, reels, floats, sinkers/ feeders, nets, stringers/ k ...

by the rough terrain of its favored

habitat In ecology, the term habitat summarises the array of resources, physical and biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species habitat can be seen as the physical ...

Taxonomy

The first known specimen of the spotted stingaree was collected off Port Noarlunga in

South Australia South Australia (commonly abbreviated as SA) is a state in the southern central part of Australia. It covers some of the most arid parts of the country. With a total land area of , it is the fourth-largest of Australia's states and territories ...

, and described by Trevor Scott in a 1954 issue of the scientific journal ''Records of the South Australian Museum''. The specific epithet ''gigas'' is

Greek Greek may refer to: Greece Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group. *Greek language, a branch of the Indo-European language family. **Proto-Greek language, the assumed last common ancestor ...

for "giant". The eastern and western forms of this ray differ slightly in coloration; the western form, called Sinclair's stingaree, has been considered a distinct separate species by some authors.

Distribution and habitat

Widely but patchily distributed along the southern coast of Australia, the spotted stingaree occurs from

Albany, Western Australia Albany ( ; nys, Kinjarling) is a port city in the Great Southern region in the Australian state of Western Australia, southeast of Perth, the state capital. The city centre is at the northern edge of Princess Royal Harbour, which is a ...

to Lakes Entrance, Victoria, including Bass Strait and the northern

Tasmania ) , nickname = , image_map = Tasmania in Australia.svg , map_caption = Location of Tasmania in AustraliaCoordinates: , subdivision_type = Country , subdi ...

n coast. It does not appear to be common, not does it aggregate any particular location. Bottom-dwelling in nature, this species inhabits the continental shelf from the intertidal zone to a depth of . It is most commonly found in and around

beds and rocky

s, and has also been recorded from

estuaries An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. Estuaries form a transition zone between river environments and maritime environmen ...

Description

The

disc of the spotted stingaree is oval in shape and slightly longer than wide; it is more circular in juveniles. The snout is fleshy and usually smoothly rounded, without a protruding tip. The eyes are tiny and followed by much larger comma-shaped spiracles, which have rounded posterior rims. There is a skirt-shaped curtain of skin with a finely fringed posterior margin between the nostrils. The floor of the small mouth bears 9–12 papillae (nipple-like structures); a further narrow patch of papillae is found on the lower jaw. The teeth are small, with roughly oval bases. The five pairs of

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 and rays, as well as deep-branching vertebrates such as lampreys. In con ...

s are short, and the pelvic fins are small and rounded. The tail measures 76–80% as long as the disc and is fairly thick, with an oval cross-section and no lateral skin folds. A serrated stinging spine is placed atop the tail and preceded by a prominent

; the

is lance-like, short, and deep. The skin is completely smooth. The disc is dark brown to black above, becoming lighter towards the margins, and sometimes with irregularly scattered dark dots. There are 2–3 rows of small whitish spots that border the disc margin and may extend onto the tail, as well as much larger pale spots arranged in groups over the middle of the back. The areas before and behind the eyes, and a pair of patches at the back of the disc, are usually free of spots. The tail has a light stripe along the midline in juveniles, and light spots in some adults; the dorsal and caudal fins are dark brown to black with whitish edges. The underside is white or nearly so; most individuals have dusky blotches and wide bands bordering the lateral disc margins. In some rays the color pattern is faint. This species can grow up to long.

Biology and ecology

During the day, the spotted stingaree is often encountered buried in sand or hidden amongst seagrass or rocks.Murch, A
Spotted stingaree
Elasmodiver.com. Retrieved on September 7, 2010. It feeds mainly on

s. As in other stingrays, it is presumably

with the developing

embryos An embryo is an initial stage of development of a multicellular organism. In organisms that reproduce sexually, embryonic development is the part of the life cycle that begins just after fertilization of the female egg cell by the male spe ...

being nourished via maternal histotroph ("

milk"). Females can produce litters of up to 13 pups. Males and females reach

sexual maturity Sexual maturity is the capability of an organism to reproduce. In humans it might be considered synonymous with adulthood, but here puberty is the name for the process of biological sexual maturation, while adulthood is based on cultural definit ...

at approximately and long respectively.

Human interactions

Compared to some of its relatives like the sparsely-spotted stingaree (''U. paucimaculatus''), the spotted stingaree is less aggressive when disturbed by humans. There is little to no fishing activity across most of this species' range, and its preference for rocky

s mostly protect it from

bottom trawl Bottom trawling is trawling (towing a trawl, which is a fishing net) along the seafloor. It is also referred to as "dragging". The scientific community divides bottom trawling into benthic trawling and demersal trawling. Benthic trawling is tow ...

s. The Southern and Eastern Scalefish and Shark Fishery (SESSF) take it as bycatch, but not in significant numbers. It may potentially be affected by

habitat degradation Habitat destruction (also termed habitat loss and habitat reduction) is the process by which a natural habitat becomes incapable of supporting its native species. The organisms that previously inhabited the site are displaced or dead, thereby ...

recreational fishing Recreational fishing, also called sport fishing or game fishing, is fishing for leisure, exercise or competition. It can be contrasted with commercial fishing, which is professional fishing for profit; or subsistence fishing, which is fishing fo ...

. Given that it is little threatened by human activity, the

(IUCN) has assessed the spotted stingaree as of

. The range of this species encompasses a number of small

Marine Protected Area Marine protected areas (MPA) are protected areas of seas, oceans, estuaries or in the US, the Great Lakes. These marine areas can come in many forms ranging from wildlife refuges to research facilities. MPAs restrict human activity for a conse ...

s (MPAs), and it would potentially benefit from the implementation of the 2004 Australian National Plan of Action for the Conservation and Management of Sharks.

References

External links

Fishes of Australia : ''Urolophus gigas''
{{Taxonbar, from=Q4667827 spotted stingaree Marine fish of Southern Australia Taxa named by Trevor D. Scott spotted stingaree Taxonomy articles created by Polbot