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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
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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.
