Ailuracantha

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Ailuracantha
Temporal range: Early Devonian
Ailuracantha.png
Artist's reconstruction of A. dorsofelis
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Placodermi
Order: Arthrodira
Family: Actinolepidae
Genus: Ailuracantha
Species:
A. dorsifelis
Binomial name
Ailuracantha dorsifelis
White, 1969

Ailuracantha is a montotypic genus of extinct placoderm from the family actinolepidae. It was discovered in the Senni Beds: a Devonian aged rock formation near the Black Mountains of Wales, and is represented by only one species: Ailuracantha dorsifelis. [1]

Contents

Etymology

The generic name Ailuracantha comes from the Greek αἴλουρος (aílouros), meaning "cat", and ἄκανθος (akanthos), meaning "spine" or "thorn"; the type species dorsifelis comes from the Latin dorsum, meaning "back," and felis, also meaning "cat." Both specific and generic names are in reference to The Cat's Back, a spur of the Black Mountains and the locality the holotype was recovered from.

Description

Ailuracantha's body plan is relatively standard for an actinolepid, possessing a small, slightly dorsoventrally flattened body with two proportionally large spines on its thoracic shield. Unlike other members of this taxonomic group, its pectoral spines possess a narrow under surface and deep mesial surface. This fish arrangement may suggest that it had greater mobility than what is inferred from observations in its relatives. The frontal region of its head shield is ornamented with small, oval-shaped tubercles, which are extremely fine on the ventral side of its body.

Paleobiology

Ailuracantha was a freshwater fish that likely lived in alluvial channels, wetlands, and oxbows on a semi-arid floodplain, as evidenced by the lithology of the rocks in which it was found. [2] It was probably a benthopelagic predator that fed on small, soft-bodied invertebrates.

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References

  1. WHITE, ERROL I. (1 September 1969). "The deepest vertebrate fossil and other arctolepid fishes*". Biological Journal of the Linnean Society. 1 (3): 293–310. doi:10.1111/j.1095-8312.1969.tb00122.x . Retrieved 30 July 2018.
  2. Owen, Geraint (March 1995). "Senni Beds of the Devonian Old Red Sandstone, Dyfed, Wales: anatomy of a semi-arid floodplain". Sedimentary Geology. 95 (3–4): 221–235. doi:10.1016/0037-0738(94)00112-8.