- Fiddler ray
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Fiddler rays Eastern fiddler ray (Trygonorrhina faciata) from Botany Bay, NSW, Australia Scientific classification Kingdom: Animalia Phylum: Chordata Class: Chondrichthyes Subclass: Elasmobranchii Order: Rajiformes Family: Rhinobatidae Genus: Trygonorrhina
J. P. Müller & Henle, 1838Species - T. faciata J. P. Müller & Henle, 1841
- T. melaleuca T. Scott, 1954
The fiddler rays or banjo sharks are a genus, Trygonorrhina, of guitarfish, family Rhinobatidae. There are two species, found along the eastern and southern coasts of Australia. They are benthic in nature, favoring shallow sandy bays, rocky reefs, and seagrass beds. The eastern fiddler is found to a depth of 120 meters and the southern fiddler to a depth of 180 meters.[1][2]
The flattened pectoral fin discs of fiddler rays are shorter and more rounded than that of other guitarfishes. Their tails are slender, with a well-developed caudal fin and two triangular dorsal fins.[3] Their snouts are translucent.[1] The fiddler rays are also distinguished from other guitarfishes in that the anterior nasal flaps of their nostrils are expanded backwards and fused together into a nasal curtain that reaches the mouth.[4]
Fiddler rays feed on bottom shellfish, crabs, and worms, which they crush between their jaws.[1] The eastern fiddler ray is known to scavenge from fish traps.[4] Like other guitarfishes, fiddler rays are ovoviviparous. The egg capsules of the southern fiddler ray are reported to be golden in color, containing three embryos each.[2] It gives birth to litters of 4-6 young per breeding cycle.[5] Fiddler rays are harmless and easily approached by divers.[1] Southern fiddler rays are taken as bycatch by commercial trawlers and by recreational fishers; the flesh is of good quality and sold in small quantities.[5]
Species
- Southern fiddler ray, Trygonorrhina fasciata J. P. Müller & Henle, 1841 This species occurs along the southern coast of Australia. It is brown with shades of yellow or olive above, with a pattern of pale lilac bands edged with dark brown and a distinctive triangular pattern behind its eyes. It has been split into an eastern (fasciata) and western (dumerilii) form which is darker yellowish brown color than the eastern form, with blue-grey bands that do not form a triangle behind the eyes. However, the two are currently considered conspecific with T. dumerilii (Castenlau, 1873) considered a junior synonym of T. fasciata. This species reaches a length of 126 cm.
- Magpie fiddler ray, Trygonorrhina melaleuca T. Scott, 1954 A very rare species known only from Gulf St Vincent in South Australia, distinguishable by its entirely bluish-black coloration. It may represent a mutant form of the southern fiddler ray.[6][7]
References
- ^ a b c d Aitken, K. (2002). Southern Fiddler Ray (Trygonorrhina dumerilii) & Eastern Fiddler Ray (Trygonorrhina faciata). Rhinobatidae. Marine Themes. Retrieved on November 21, 2008.
- ^ a b Froese, Rainer, and Daniel Pauly, eds. (2011). "Trygonorrhina fasciata" in FishBase. February 2011 version.
- ^ McGrouther, M. (March 2006). Eastern Fiddler Ray, Trygonorrhina faciata . Australian Museum. Retrieved on November 21, 2008.
- ^ a b Compagno, L.J.V. and Last, P.R. (1999). "Rhinobatidae: Guitarfishes". In Carpenter, K.E. and Niem, V.H.. FAO identification guide for fishery purposes. The living marine resources of the Western Central Pacific. Rome: Food and Agricultural Organization of the United Nations. ISBN 9251043027.
- ^ a b Reardon, M. (2003). Trygonorrhina fasciata. In: IUCN 2008. IUCN Red List of Threatened Species. Downloaded on November 21, 2008.
- ^ Ferrari, A. and A. (2002). Sharks. New York: Firefly Books. ISBN 1552096297.
- ^ Froese, Rainer, and Daniel Pauly, eds. (2011). "Trygonorrhina melaleuca" in FishBase. February 2011 version.
Categories:- Rhinobatidae
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