The smallmouth spiny eel (''Polyacanthonotus rissoanus''), also called the shortspine tapirfish, is a species of
deep-sea spiny eel.
Description
The smallmouth spiny eel is silver or brown in colour, with a maximum length of . It has 26–36 dorsal
soft rays
Fish anatomy is the study of the form or morphology of fish. It can be contrasted with fish physiology, which is the study of how the component parts of fish function together in the living fish. In practice, fish anatomy and fish physiology co ...
. It looks similar to ''
Polyacanthonotus africanus
''Polyacanthonotus'' is a genus of spiny eels, with these currently recognized species:
* '' Polyacanthonotus africanus'' ( Gilchrist & von Bonde, 1924)
* '' Polyacanthonotus challengeri'' ( Vaillant, 1888) (longnose tapirfish)
* '' Polyacanth ...
'' but its
lateral line
The lateral line, also called the lateral line organ (LLO), is a system of sensory organs found in fish, used to detect movement, vibration, and pressure gradients in the surrounding water. The sensory ability is achieved via modified epithelial ...
is lighter and less distinct. It has a small mouth and a short preoral snout. Mature males are distinguished by their black
nostrils.
Habitat
The smallmouth spiny eel lives in the Arctic waters off of
Canada and in the
North Atlantic Ocean off of
Iceland,
Ireland and
Great Britain; it has also been observed in the waters off
South Africa and in the
Tasman Sea. It is a
benthic
The benthic zone is the ecological region at the lowest level of a body of water such as an ocean, lake, or stream, including the sediment surface and some sub-surface layers. The name comes from ancient Greek, βένθος (bénthos), meaning "t ...
and
bathydemersal
Demersal fish, also known as groundfish, live and feed on or near the bottom of seas or lakes (the demersal zone).Walrond Carl . "Coastal fish - Fish of the open sea floor"Te Ara - the Encyclopedia of New Zealand. Updated 2 March 2009 They occ ...
species, living at depths of .
Behaviour
''Polyacanthonotus rissoanus'' feeds on
coelenterates,
worms and
crustaceans.
References
Notacanthidae
Fish described in 1857
Taxa named by Filippo De Filippi
Taxa named by Jean Baptiste Vérany
{{Notacanthiformes-stub