12: PSEUDOTRIAKIDAE (FALSE CATSHARKS)
12.1 Pseudotriakis microdon: 93 cm immature specimen (Atlantic; after Bigelow & Schroeder, 1948).
Family No. 12: PSEUDOTRIAKIDAE
by A.J. Bass
False catsharks
Vals kathaaie
Large deep-water sharks resembling the Scyliorhinidae
but with a long first dorsal fin (its base about as long as
upper caudal fin), its axil over or in front of pelvic origin. A
single genus, Pseudotriakis Capello, 1868, with 1 or 2
species.
12.1 Pseudotriakis microdon
Brito Capello, 1867
Pseudotriakis microdon Brito Capello, 1867: 316, PI. 5 (Setubal, Portugal); Bass et aI., 1975: 35*.
Teeth in several fUilctional series, arranged diagonally in upper jaws,
perpendicularly in lower jaws.
Uniform dark brownish-grey. Found near bottom of
deep water in North Atlantic and equatorial western Indian
Ocean. Live-bearing; 2 pups per litter, born at about 90 cm;
attains almost 3 m.
Family No. 13: SPHYRNIDAE
by A.J. Bass
Hammerhead sharks
Hamerkophaaie
Head flattened and greatly expanded laterally with the
eyes on the ends of the lateral expansions. Otherwise
similar to the genus Carcharhinus (Carcharhinidae). Body
grey dorsally, paler below. One genus, Sphyrna Rafinesque, 1810, with several species, 3 in our area.
KEY TO SPECIES
1a Front edge of head without a median indentation
or "scallop" ......................................................... S. zygaena
1b Front edge of head with a median indentation or scallop ........... 2
2a Rear margin of V markedly concave; teeth with
definite serrations easily visible to the naked eye; 2nd
D higher than length of 3rd gill slit .......................... S. mokarran
2b Rear margin of V almost straight, at most only slightly
concave; teeth with smooth or at most weakly serrated
cusps; 2nd D not higher than length of 3rd gill slit ............ S. lewini
13.1 Sphyrna lewini: 47 cm immature female (Natal). Ventral view of head; T = teeth.
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