The small-spotted catshark (Scyliorhinus canicula), also known as the sandy dogfish,[1]lesser-spotted dogfish, rough-hound or morgay (in Scotland and Cornwall),[2] is a catshark of the familyScyliorhinidae. It is found on the continental shelves and the uppermost continental slopes off the coasts of Norway and the British Isles south to Senegal and in the Mediterranean, between latitudes 63° N and 12° N. It can grow up to a length of 1 m (3 ft 3 in), and it can weigh more than 2 kg (4.4 lb).[3] It is found primarily over sandy, gravelly, or muddy bottoms from depths of a few metres down to 400 m (1,300 ft).[4]S. canicula is one of the most abundant elasmobranchs in the northeast Atlantic and Mediterranean Sea. The majority of the populations are stable in most areas.[5]
S. canicula are small, shallow-water sharks with a slender body and a blunt head. The two dorsal fins are located towards the tail end of the body. The texture of their skin is rough, similar to the coarseness of sandpaper.[6] The nostrils are located on the underside of the snout and are connected to the mouth by a curved groove. The upper side of the body is greyish brown with dark brown spots. The underside is a light greyish white. The teeth of S. canicula are larger in males than in females; in addition, male S. canicula from West African waters have stronger, larger, and more calcinated jaws. The differences in mouth dimensions and tooth length between males and females, and between immature and adult males, could be due to different feeding habits or adaptations for reproductive behaviour.[7]
ReproductionEdit
Egg with mature embryo
S. canicula is oviparous. They deposit egg cases protected by a horny capsule with long tendrils. Egg cases are mostly deposited on macroalgae in shallow coastal waters. When the egg cases are deposited farther from shore, they are placed on sessile erect invertebrates. Egg cases usually measure 4 cm by 2 cm, without ever exceeding 6 cm (2.4 in).[8] These egg cases can be found around the coasts of Europe. The embryos develop for 5–11 months depending on the sea temperature, and the young are born with a measurement of 9–10 cm (3.5–3.9 in).
Spawning can take place almost year round.[8] However, there can be seasonal patterns in spawning activity as well. For example, S. canicula females located off the Mediterranean coast of France lay their eggs from March to June and in December. In the waters surrounding Great Britain, egg laying occurs in spring with a gap between August and October. On the Tunisian coast, the sharks lay their eggs starting in spring, peaking in the summer and then slightly decreasing during autumn.[9] Males reach sexual maturity with a length of about 37.1–48.8 cm (14.6–19.2 in). Females reach sexual maturity with a length of 36.4–46.7 cm (14.3–18.4 in).[10]
FeedingEdit
S. canicula is an opportunistic species, preying on a wide variety of organisms. Decapod crustaceans, molluscs and fishes are their main prey, but echinoderms, polychaetes, sipunculids and tunicates may also be eaten.[4] Dietary preferences change with age; younger animals prefer small crustaceans, while older animals prefer hermit crabs and molluscs. Feeding intensity is highest during the summer due to the higher availability of prey life. Diet composition varies with body size.
There are no significant differences in feeding habits between male and female S. canicula.[4] Juveniles of S. canicula feed by anchoring the prey item on the dermal denticles near their tail, and tearing bite-sized pieces off with rapid head and jaw movements, a behaviour known as "scale rasping". Use of dermal denticles to assist in feeding was first documented in this species.[11]
PsychologyEdit
A study published in 2014 at Exeter University showed that individual small-spotted catsharks have different personality traits. Some individuals are more sociable than others, some more aggressive, some more exploratory in nature.[12][13]
Model organismEdit
S. canicula is well-suited for comparative analysis of gastrulation for several reasons.
It is harvested in large numbers along all the coasts of Europe, and it is the only known elasmobranch species from which individuals at any stage of development can be obtained in abundance at any time of year.[5]
Fertilization is internal, but eggs are laid at early stages of development, before the formation of the blastocoel. Once laid, they can go on developing normally in the laboratory, simply in oxygenated seawater.[14]
The size and accessibility of the embryo makes analysis easier.
Five well-characterized stages can be distinguished between the onset of gastrulation and the beginning of neurulation.[14]
Threat levelEdit
S. canicula is one of the most abundant elasmobranchs in the northeast Atlantic and Mediterranean. It is regularly caught by near-shore fisheries, but the majority taken by commercial fishermen and recreational anglers are discarded. Studies have shown that post-discard survival rates are extremely high, around 98%. Although localized depletion may have occurred in some areas, surveys have shown that populations are stable or are even increasing throughout the majority of its range. However, continued monitoring of landing and discarded data is important to avoid any future decline.
This species is currently listed as being of least concern on the IUCN Red List of Threatened Species, because there is no evidence to indicate that the global population has declined significantly. Since 2003, there have been yearly releases of these sharks into the Gullmarn fjord in Sweden by the public aquaria Havets Hus in Lysekil. More than 90 sharks have been released since 2003, of which one was found in southern Norway 10 years after its release. This means that these sharks can reach at least an age of 14 years.[15]
Human consumption and useEdit
S. canicula is currently of low commercial value. In the recent past, it was one of the species sold in English and Scottish fish and chip shops as rock salmon, rock eel, huss, or sweet william. In other parts of its range, it is occasionally baked or used in fish soup.[2] Its hard skin has been used as a substitute for pumice, but the fact that catsharks have to be skinned before they can be filleted discourages commercial fishermen from catching this species.[16]
^. Archived from the original on 2018-01-09. Retrieved 2018-01-09.
^ abDavidson, A. (2004). North Atlantic Seafood: A Comprehensive Guide with Recipes (third ed.). Ten Speed Press. p. 168. ISBN1-58008-450-8.
^ Wilson, Don E.; Burnie, David (2001). Animal: The Definitive Visual Guide to the World's Wildlife. New York City: Dorling Kindersley Publishing. p. 624. ISBN0-7894-7764-5.
^ abcRodriguez-Cabello, C., Sanchez, F., Olaso, I. 2007. Distribution patterns and sexual segregations of Scyliorhinus canicula (L.) in the Cantabrian Sea. Journal of Fish Biology. 70: 1568–1586
^ abBallard, W., Mellinger, J., Lechenault, H. 2005. A series of normal stages for development of Scyliorhinus canicula the lesser spotted dogfish (Chondrichthyes: Scyliorhinidae). Journal of Experimental Zoology. 267: 318–336
^McNeill, Ian. "Habitas :: National Museums Northern Ireland." Habitas :: National Museums Northern Ireland. N.p., n.d. Web. 16 Dec. 2010. <http://www.habitas.org.uk>
^Erdogan, Z., Koc, H., Cakir, D. 2004. Sexual Dimorphism in the Small-Spotted Catshark, Scyliorhinus Canicula (L., 1758), From the Edremit Bay (Turkey). Ser. his. nat, 262: 4–18.
^ abEllis, J.R., Shackley, S.E. 1997. The reproductive biology of Scyliorhinus canicula in the Bristol Channel, U.K. Journal of Fish Biology, 51: 361–372
^Capae, C., Reynaud, C.,Vergne, Y., Quignard, J. 2008. Biological observations on the smallspotted catshark Scyliorhinus canicula (Chondrichthyes: Scyliorhinidae) off the Languedocian coast (southern France, northern Mediterranean). Pan-American Journal of Aquatic Sciences, 3: 282–289
^Ivory, P., Jeal, F., Nolan, C.P. 2005. Age determination, growth and reproduction in the lesser-spotted dogfish, Scyliorhinus canicula (L.). J. Northw. Atl. Fish. Sci., 35: 89–106.
^Southall, E.J., Sims, D.W. 2003. Shark skin: a function in feeding. Proceedings of the Royal Society of London Series B-Biological Sciences, 270: 47–49.
^"Sharks have personality traits, study suggests".
^Jacoby, David M. P.; Fear, Lauren N.; Sims, David W.; Croft, Darren P. (2014). "Shark personalities? Repeatability of social network traits in a widely distributed predatory fish". Behavioral Ecology and Sociobiology. 68 (12): 1995–2003. doi:10.1007/s00265-014-1805-9. hdl:10871/16094. S2CID 14730238.
^ abMazan, S., Sauka-Splengler, T. 2004. "Gastrulation in the chondrichthyan, the dogfish Scyliorhinus canicula." Gastrulation: from cells to embryo. Ed. Claudio D. Stern. Cold Spring Harbor Laboratory Press. New York, NY, 151–155 pp.
^"Dogfish". Britishseafishing.co.uk. 29 June 2012.
External linksEdit
Video with embryo of a small-spotted catshark inside the egg on YouTube
Media related to Scyliorhinus canicula at Wikimedia Commons
Data related to Scyliorhinus canicula at Wikispecies
August 25, 2023
small, spotted, catshark, small, spotted, catshark, scyliorhinus, canicula, also, known, sandy, dogfish, lesser, spotted, dogfish, rough, hound, morgay, scotland, cornwall, catshark, family, scyliorhinidae, found, continental, shelves, uppermost, continental, . The small spotted catshark Scyliorhinus canicula also known as the sandy dogfish 1 lesser spotted dogfish rough hound or morgay in Scotland and Cornwall 2 is a catshark of the family Scyliorhinidae It is found on the continental shelves and the uppermost continental slopes off the coasts of Norway and the British Isles south to Senegal and in the Mediterranean between latitudes 63 N and 12 N It can grow up to a length of 1 m 3 ft 3 in and it can weigh more than 2 kg 4 4 lb 3 It is found primarily over sandy gravelly or muddy bottoms from depths of a few metres down to 400 m 1 300 ft 4 S canicula is one of the most abundant elasmobranchs in the northeast Atlantic and Mediterranean Sea The majority of the populations are stable in most areas 5 Small spotted catsharkConservation statusLeast Concern IUCN 3 1 Scientific classificationDomain EukaryotaKingdom AnimaliaPhylum ChordataClass ChondrichthyesOrder CarcharhiniformesFamily ScyliorhinidaeGenus ScyliorhinusSpecies S caniculaBinomial nameScyliorhinus canicula Linnaeus 1758 Range in blue Contents 1 Description 2 Reproduction 3 Feeding 4 Psychology 5 Model organism 6 Threat level 7 Human consumption and use 8 See also 9 References 10 External linksDescription Edit Adult fish in aquariumS canicula are small shallow water sharks with a slender body and a blunt head The two dorsal fins are located towards the tail end of the body The texture of their skin is rough similar to the coarseness of sandpaper 6 The nostrils are located on the underside of the snout and are connected to the mouth by a curved groove The upper side of the body is greyish brown with dark brown spots The underside is a light greyish white The teeth of S canicula are larger in males than in females in addition male S canicula from West African waters have stronger larger and more calcinated jaws The differences in mouth dimensions and tooth length between males and females and between immature and adult males could be due to different feeding habits or adaptations for reproductive behaviour 7 Reproduction Edit Egg with mature embryoS canicula is oviparous They deposit egg cases protected by a horny capsule with long tendrils Egg cases are mostly deposited on macroalgae in shallow coastal waters When the egg cases are deposited farther from shore they are placed on sessile erect invertebrates Egg cases usually measure 4 cm by 2 cm without ever exceeding 6 cm 2 4 in 8 These egg cases can be found around the coasts of Europe The embryos develop for 5 11 months depending on the sea temperature and the young are born with a measurement of 9 10 cm 3 5 3 9 in Spawning can take place almost year round 8 However there can be seasonal patterns in spawning activity as well For example S canicula females located off the Mediterranean coast of France lay their eggs from March to June and in December In the waters surrounding Great Britain egg laying occurs in spring with a gap between August and October On the Tunisian coast the sharks lay their eggs starting in spring peaking in the summer and then slightly decreasing during autumn 9 Males reach sexual maturity with a length of about 37 1 48 8 cm 14 6 19 2 in Females reach sexual maturity with a length of 36 4 46 7 cm 14 3 18 4 in 10 Feeding EditS canicula is an opportunistic species preying on a wide variety of organisms Decapod crustaceans molluscs and fishes are their main prey but echinoderms polychaetes sipunculids and tunicates may also be eaten 4 Dietary preferences change with age younger animals prefer small crustaceans while older animals prefer hermit crabs and molluscs Feeding intensity is highest during the summer due to the higher availability of prey life Diet composition varies with body size There are no significant differences in feeding habits between male and female S canicula 4 Juveniles of S canicula feed by anchoring the prey item on the dermal denticles near their tail and tearing bite sized pieces off with rapid head and jaw movements a behaviour known as scale rasping Use of dermal denticles to assist in feeding was first documented in this species 11 Psychology EditA study published in 2014 at Exeter University showed that individual small spotted catsharks have different personality traits Some individuals are more sociable than others some more aggressive some more exploratory in nature 12 13 Model organism EditS canicula is well suited for comparative analysis of gastrulation for several reasons It is harvested in large numbers along all the coasts of Europe and it is the only known elasmobranch species from which individuals at any stage of development can be obtained in abundance at any time of year 5 Fertilization is internal but eggs are laid at early stages of development before the formation of the blastocoel Once laid they can go on developing normally in the laboratory simply in oxygenated seawater 14 The size and accessibility of the embryo makes analysis easier Five well characterized stages can be distinguished between the onset of gastrulation and the beginning of neurulation 14 Threat level EditS canicula is one of the most abundant elasmobranchs in the northeast Atlantic and Mediterranean It is regularly caught by near shore fisheries but the majority taken by commercial fishermen and recreational anglers are discarded Studies have shown that post discard survival rates are extremely high around 98 Although localized depletion may have occurred in some areas surveys have shown that populations are stable or are even increasing throughout the majority of its range However continued monitoring of landing and discarded data is important to avoid any future decline This species is currently listed as being of least concern on the IUCN Red List of Threatened Species because there is no evidence to indicate that the global population has declined significantly Since 2003 there have been yearly releases of these sharks into the Gullmarn fjord in Sweden by the public aquaria Havets Hus in Lysekil More than 90 sharks have been released since 2003 of which one was found in southern Norway 10 years after its release This means that these sharks can reach at least an age of 14 years 15 Human consumption and use EditS canicula is currently of low commercial value In the recent past it was one of the species sold in English and Scottish fish and chip shops as rock salmon rock eel huss or sweet william In other parts of its range it is occasionally baked or used in fish soup 2 Its hard skin has been used as a substitute for pumice but the fact that catsharks have to be skinned before they can be filleted discourages commercial fishermen from catching this species 16 See also Edit Sharks portalGreater spotted dogfishReferences Edit Sandy dogfish Archived from the original on 2018 01 09 Retrieved 2018 01 09 a b Davidson A 2004 North Atlantic Seafood A Comprehensive Guide with Recipes third ed Ten Speed Press p 168 ISBN 1 58008 450 8 Wilson Don E Burnie David 2001 Animal The Definitive Visual Guide to the World s Wildlife New York City Dorling Kindersley Publishing p 624 ISBN 0 7894 7764 5 a b c Rodriguez Cabello C Sanchez F Olaso I 2007 Distribution patterns and sexual segregations of Scyliorhinus canicula L in the Cantabrian Sea Journal of Fish Biology 70 1568 1586 a b Ballard W Mellinger J Lechenault H 2005 A series of normal stages for development of Scyliorhinus canicula the lesser spotted dogfish Chondrichthyes Scyliorhinidae Journal of Experimental Zoology 267 318 336 McNeill Ian Habitas National Museums Northern Ireland Habitas National Museums Northern Ireland N p n d Web 16 Dec 2010 lt http www habitas org uk gt Erdogan Z Koc H Cakir D 2004 Sexual Dimorphism in the Small Spotted Catshark Scyliorhinus Canicula L 1758 From the Edremit Bay Turkey Ser his nat 262 4 18 a b Ellis J R Shackley S E 1997 The reproductive biology of Scyliorhinus canicula in the Bristol Channel U K Journal of Fish Biology 51 361 372 Capae C Reynaud C Vergne Y Quignard J 2008 Biological observations on the smallspotted catshark Scyliorhinus canicula Chondrichthyes Scyliorhinidae off the Languedocian coast southern France northern Mediterranean Pan American Journal of Aquatic Sciences 3 282 289 Ivory P Jeal F Nolan C P 2005 Age determination growth and reproduction in the lesser spotted dogfish Scyliorhinus canicula L J Northw Atl Fish Sci 35 89 106 Southall E J Sims D W 2003 Shark skin a function in feeding Proceedings of the Royal Society of London Series B Biological Sciences 270 47 49 Sharks have personality traits study suggests Jacoby David M P Fear Lauren N Sims David W Croft Darren P 2014 Shark personalities Repeatability of social network traits in a widely distributed predatory fish Behavioral Ecology and Sociobiology 68 12 1995 2003 doi 10 1007 s00265 014 1805 9 hdl 10871 16094 S2CID 14730238 a b Mazan S Sauka Splengler T 2004 Gastrulation in the chondrichthyan the dogfish Scyliorhinus canicula Gastrulation from cells to embryo Ed Claudio D Stern Cold Spring Harbor Laboratory Press New York NY 151 155 pp Bevarande Dogfish Britishseafishing co uk 29 June 2012 External links EditVideo with embryo of a small spotted catshark inside the egg on YouTube Media related to Scyliorhinus canicula at Wikimedia Commons Data related to Scyliorhinus canicula at Wikispecies Retrieved from https en wikipedia org w index php title Small spotted catshark amp oldid 1168691711, wikipedia, wiki, book, books, library,
