Archive for the ‘Chondrichthyes (Cartilaginous Fishes)’ Category:
Rat or Rabbit Fish
Most fishes with a skeleton of cartilage rather than bone belong to the rays and sharks (suborder Elsamobranchii) A small second group, the chimaeras of the suborder Holocephali, are strange-looking deep-sea fishes. The rat fish or rabbit fish (not to be confused with the warm-water rabbit fishes of the family Siganidae, sometimes kept in aquariums) is an example. It has a long whip-like tail, big staring eyes, large pectoral fins, and a large dorsal fin with a long spine behind the head. Its small mouth has lips and rabbit-like tooth plates. Around Iceland and Norway it migrates to shallow seas to breed, and is sometimes caught by fishermen.
Scientific name : Chimaera monstrosa
Classification : Subclass Holocephali.
Order : Chimaeriformes (chimaeras)
Family : Chimaeridae
Size : Up to about 1.5m (5ft) long
Distribution : Eastern and northern Atlantic; Mediterranean; possibly other oceans
Habitat : Deep temperate and cold waters, mainly at 300-500m (1000-1600ft)
Diet : Mainly bottom-living invertebrates
Reproduction : Spawns in spring; eggs in slender cases, 18cm (7in) long
Common Eagle Ray Fish
Eagle rays are aptly named, because their pectoral disc is much wider han it is long, so the fish appears to have wings. They are also (along with the manta rays; much more active swimmers than most other rays, ‘flying’ through the water by flapping their wings, and even leaping into the air. They use their flat, plate-like teeth to crush crustacean and mollusc shells. The common eagle ray has a venomous tail spine but is not regarded as dangerous. The huge spotted eagle ray (Aetobatus narinari), up to 3m (10ft) wide, is common worldwide in the tropics and subtropics, including waters off the southern and south-eastern USA.
Scientific name : Myliobatis aquila
Classification : Order Myliobatiformes (great rays); sometimes included in Rajiformes
Family : Myliobatidae
Size : Up to about 1.8m (6ft) wide
Distribution : Eastern Atlantic from British Isles to South Africa; Mediterranean
Habitat : Temperate and tropical coastal waters; offshore to 300m (1000ft) deep
Diet : Mainly bottom-living crustaceans and molluscs; also fish
Reproduction : Ovoviviparous; three to seven young born after 6-8-month gestation