Kitefin-Cookiecutter-Pygmy-Taillight-Sharks The Family Dalatiidae Kitefin-Cookiecutter-Pygmy-Taillight-Sharks Tiffany Adams September 18, 2007 Elasmobiology

Taxonomy Squaliformes Dalatiidae 7 genera 9 species Dalatias licha Euprotomicroides zantedeschia Euprotomicrus bispinatus Heteroscymnoides marleyi Isistius brasuliensis Isistius plutodus Mollisquama parini Squaliolus aliae Squaliolus laticaudus Taxonomy changes? Most of these species were previously listed under the families Scymnorhinidae or Squalidae, along with many other genera. Fishbase (ref. Nelson 1994) lists Dalatiidae as including 18 genera and 39 species. Taxonomy above is from our text (Carrier 2004.) Sleeper sharks? Most references still label Dalatiidae as “Sleeper Sharks” even thought the sleeper shark belongs to the genus Somniosus under the family Sominiosidae. A couple websites refer to Dalatiidae as “Kitefin Sharks” which still seems inappropriate given that this name fits only 1 of the 9 species.

Dalatiidae Species Dalatias licha- kitefin shark Euprotomicrus bispinatus- pygmy shark Euprotomicroides zantedeschia- taillight shark Squaliolus laticaudus- spined pygmy shark Isistius brasiliensis- cookiecutter shark Squaliolus aliae- smalleye pygmy shark Isistius plutodus- largetooth cookiecutter shark Heteroscymnoides marleyi- longnose pygmy shark Mollisquama parini- pocket shark (not pictured)

Characteristics of Dalatiidae Most are small, all under 60 cm except Dalatias (up to 200cm) Both dorsal fins generally without spines and similar in size Caudal fin with subterminal notch No anal fin Five gill slits No nictating eyelid Unicuspid teeth in both jaws- upper are slender and lanceolate, lower are broad and overlapping

Biology/Ecology Reproduction Ovoviviparous, relatively small clutch sizes ranging from 6-20 No information available on reproductive age or interval   Prey Small bony fish, cephalopods, crustaceans Dalatias (kitefin)- skates and sharks Isistius (cookiecutter)- large fish and cetaceans Population status Most species abundance not well known IUCN lists all as either DD (data deficient) or LC (least concern)

Distribution Oceanic, Pelagic-benthopelagic Circumglobal in temperate to tropical seas

Isistius brasiliensis The cookiecutter shark, an ectoparasite Although cookie cutter sharks only grow to be around 50-60cm, they are known to take bites out of cetaceans, sea lions, larger fish and other sharks. “The cookiecutter shark has specialized suctorial lips and a strongly modified pharynx that allow it to attach to the sides of it prey. It then drives its saw-like lower dentition into the skin and flesh of its victim, twists about to cut out a conical plug of flesh, then pull free with the plug cradled by its scoop-like lower jaw and held by the hook-like upper teeth.” (Campagno 1984)

Works Cited Related Articles Allen, T. 1999. Shark Almanac. Lyons Press, New York. Pp. 49-58. Carrier, J,, Musick, J., and Heithaus, M. 2004. Biology of Sharks and Their Relatives. CRC Press, Boca Raton. Pp. 56-58, 65-66. Compagno, L.J.V., 1984. FAO species catalogue. Vol. 4. Sharks of the world. An annotated and illustrated catalogue of shark species known to date. Part 1 - Hexanchiformes to Lamniformes. FAO Fish. Synop. 125(4/1):1-249. IUCN 2006. 2006 IUCN Red List of Threatened Species. <http://www.iucnredlist.org>. Downloaded on 13 September 2007. Nelson, J. 1984. Fishes of the World. 2nd Ed. John Wiley & Sons, Inc., New York. Pp. 56-58. Parker, S. 1999. The Encyclopedia of Sharks. Firefly Books, Buffalo. Perrine, D. 1999. Sharks and Rays of the World. Voyageur Press, Hong Kong. Pp. 80, 105-106. Steel, R. 1985. Sharks of the World. Facts on File, Inc., New York. Pp. 140-150. Related Articles Cunha, C. and Gonzalez, M. 2006. Pregnancy in Squaliolus laticaudus (Elasmobranch: Dalatiidae) from Brazil. Environmental Biology of Fishes. 75(4):465-469. Gadig, O. and Gomes, U. 2002. First report on embryos of Isistius brasiliensis. Journal of Fish Biology. 60(5):1322-1325. Myagkov, N. 1984. Unusual brain structure of luminous shark, Isistius brasiliensis (Dalatiidae). Journal of Ichthyology. 24(2):109-112. Perrotta, R. G. 2004. Kitefin shark Dalatia licha (Dalatiidae)fishery in the northeastern Atlantic and some recommendations for elasmobranchs explotation. Revista de Investigación y Desarrollo Pesquero, 16:97-101 <http://hdl.handle.net/1834/1501> Downloaded on 16 September 2007. Yusuke, S. et al. 1999. First record of the pygmy shark, Euprotomicrus bispinatus (Dalatiiformes: Dalatiidae) from Fiji. Journal of National Fisheries University. 47(4):139-143.