Spikefish

The spikefishes (family Triacanthodidae) are ray-finned fishes related to the pufferfishes and triggerfishes. They live in deep waters; more than 50 m (160 ft), but above the continental shelves. They are found in the Atlantic, Indian Ocean, and the west-central Pacific.^[2]

Spikefishes Temporal range: Oligocene–Recent PreꞒ Ꞓ O S D C P T J K Pg N
Parahollardia lineata
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Actinopterygii
Order:	Tetraodontiformes
Suborder:	Triacanthoidei
Family:	Triacanthodidae T. N. Gill, 1862
Subfamilies and genera [1]
see text

The spikefishes are quite variable in form, with some species having tubular snouts (greatly elongated in Halimochirurgus and Macrorhamphosodes), and others have spoon-like teeth for scraping the scales off other fishes. Depending on the exact species involved, they reach a maximum length of about 5–22 centimetres (2.0–8.7 in).

While spikefish are shaped in a wide variety of different colors, sizes, and shapes, they can characterized by their similarities of having a dense body with relatively thick skin, a large amount of tiny yet spiky scales, two dorsal fins of which the first contains six spines and twelve to eighteen soft spines along the second, a rounded caudal fin, small and terminal mouth with at least 10 average sized conical teeth.

Taxonomy

The spikefish family, Triacanthodidae, was first proposed in 1862 by the American biologist Theodore Gill^[3] and, in 1968, James C. Tyler classified it within the suborder Triacanthoidei alongside the Triacanthidae, as well as proposing the subfamily Hollardinae.^[4] The 5th edition of Fishes of the World classifies this as suborder of the order Tetraodontiformes.^[5]

Subfamiles and genera

The spikefish family, Triacanthodidae, is divided into two subfamilies and eleven genera as follows:^[6]

• Subfamily Hollardiinae Tyler, 1968
  • Genus Hollardia Poey, 1861
  • Genus Parahollardia Fraser-Brunner, 1941
  • Genus †Prohollardia Tyler, 1993 (fossil; Oligocene)^[7]
• Subfamily Triacanthodinae Gill, 1862
  • Genus Atrophacanthus Fraser-Brunner, 1950
  • Genus Bathyphylax Myers 1934
  • Genus †Carpathospinosus Tyler, 1993 (fossil; Oligocene)^[7]
  • Genus Halimochirurgus Alcock, 1899
  • Genus Johnsonina Myers, 1934
  • Genus Macrorhamphosodes Fowler, 1934
  • Genus Mephisto Tyler, 1966
  • Genus Paratriacanthodes Fowler, 1934
  • Genus Triacanthodes Bleeker, 1857
  • Genus Tydemania Weber, 1913