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Lamnidae Greek: lamna = shark
Diagnostic Features • Head long but shorter than trunk • Snout long, pointed, conical • Eyes moderately large • Large mouth • Gill openings extending to surface of head • First dorsal high, large, erect • Second dorsal and anal fins tiny • Pectorals large and narrow • Pelvic fins smaller than dorsal but larger than anal fins • Caudal lunate with upper lobe longer than second lobe • Peduncle depressed with strong keels
Habitat and Distribution • Tropical to cold-temperate • Active swimmers • Continental and insular waters • Surf line to outer shelves • Not past 1280 m deep
Reproduction • Ovoviviparous • Non-placental • Believed to be intrauterine cannibals • Very little known • Reproductive cycles from 1 to 3 years
Food • Sharks • Whale carcasses • Rays • Marine birds and reptiles • Teleosts • Marine Mammals • Squids
Predators • Orcas • Larger sharks • Humans
Extinct Relatives • Carcharodon megalodon • Late Pliocene • 13 m long, approx. 50 tons
Threat to Humans • Apex predators • Large range and habitat guarantees interaction • Large size means more damage if attacked • Most attacks short-lived, just ‘bite and run’s or mistaken identity • Less than 50 reported bites in 2006
Genera Carcharodon Isurus Lamna
Carcharodon • Species: C. carcharias vulnerable • Unique: Teeth serrated, uppers flat with triangular cusps • Human interest: big game fish, taken in as bycatch, meat eaten fresh, salted, and smoked, oil for vitamins, skin for leather, fin for shark-fin soup, jaws for ornament
Isurus • Species: • I. oxyrinchus low risk/near threatened shortfin mako • I. paucus vulnerable longfin mako • Unique: No cusplets on teeth, first dorsal behind pectorals, second dorsal in front of anal fin origin • Human interest: prize game fish due sport and high quality meat, numerous fisheries, oil used for vitamins, fins for shark-fin soup, skin for leather, jaws for ornaments, meat eaten fresh, frozen, salted, smoked, and dried
Lamna • Species: • L. ditropisdata deficient salmon • L. nasus vulnerable porbeagle • Unique: Lateral cusplets on teeth, first dorsal over pectorals, second dorsal over anal fin origin, secondary keel on caudal • Human interest: fished in North Pacific, skin used for leather, oil from liver, fins for shark-fin soup, meat eaten in Japan, Alaska and California
References • Cassoff, RM, Campana, SE, and Myklevoll, S. (2007). Changes in baseline growth and maturation parameters of Northwest Atlantic porbeagle, Lamna nasus, following heavy exploitation. Canadian J of Fisheries and Aq Sciences64 (1): 19-29. • 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 Fisheries Synopsis 125: 1–249. • Donley, JA, Shadwick, RE, Sepulveda, CA, Konstantinidis, P, and Gemballa, S. (2005). Patterns of red muscle strain/activation and body kinematics during steady swimming in a lamnid shark, the shortfin mako (Isurus oxyrinchus). J of Exp Bio 208 (12): 2377-2387. • Saidi, B, Bradai, MN, Bouain, A, Guelorget, O, and Capape, C. (2005). Capture of a pregnant female white shark, Carcharodon carcharias (Lamnidae) in the Gulf of Gabes (southern Tunisia, Central Mediterranean) with comments on oophagy in sharks. Cybium29 (3): 303-307. • Weng, KC, Boustany, AM, Pyle, P, Anderson, SD, Brown, A, and Block, BA. (2007). Migration and habitat of white sharks (Carcharodon carcharias) in the eastern Pacific Ocean. Marine Biology152 (4): 877-894. • Wilga, CD. (2005). Morphology and evolution of the jaw suspension in lamniform sharks. J of Morphology265 (1): 102-119.