Lamnidae


Mackerel sharks
Characteristic features:
Keys:

Key adapted from Compagno, 2001.1

Lamnidae species
    1. Origin of first dorsal fin level with or slightly forward of pectoral-fin rear tips (Fig. 1a); anal-fin origin behind second dorsal-fin base (Fig. 2a); upper teeth with triangular and strongly serrated cusps (Fig. 3a) Carcharodon carcharias
    2. Origin of first dorsal fin level behind pectoral-fin rear tips (Fig. 1b); anal-fin origin below midbase or insertion of second dorsal fin (Fig. 2b,c); upper teeth with narrow and smooth-edged cusps (Fig. 3b,c) 2
    1. Snout acutely pointed, it’s under surface white (Fig. 4a); pectoral fins much shorter than head, tips narrowly to acutely pointed (Fig. 5a); anal-fin origin about level with midbase of second dorsal fin (Fig. 2b); cusps of upper and lower anterior teeth recurved at bases but with tips reversed and curving outwards Isurus oxyrinchus
    2. Snout narrowly to bluntly pointed, its undersurface dusky (Fig. 4b); pectoral fins about as long as head, more broadly tipped (Fig. 5b); anal-fin origin about level with second dorsal-fin insertion (Fig. 2c); cusps of upper and lower anterior teeth straighter, with tips not reversed Isurus paucus
Similar families:

Carcharhinidae
Whaler sharks

Carcharhinidae feature image

Carcharhinidae differ in having well-developed nictitating lower eyelids (vs. no nictitating lower eyelids); a strongly asymmetrical caudal fin with the upper lobe longer than the lower (vs. caudal fin lunate and near symmetrical, upper and lower lobes of similar length); a caudal peduncle not greatly flattened dorsoventrally (vs. caudal peduncle strongly flattened dorsoventrally and expanded laterally); a longitudinal keel on caudal peduncle weak (Prionace glauca) or absent (vs. prominent, extending well out from peduncle) and intestinal valve scroll type (vs. ring type).

Species:
References:
  1. Carpenter K, Niem V, Compagno L. Lamnidae. In: FAO Species Identification Guide for Fishery Purposes. The Living Marine Resources of the Western Central Pacific. Volume 2. Cephalopods, Crustaceans, Holothurians and Sharks. Vol 2. Rome: FAO Library; 2001:1274-1278. http://www.fao.org/3/w7192e/w7192e00.htm.