Shortspine thornyhead
Encyclopedia
The shortspine thornyhead (Sebastolobus alascanus) is a species of fish
in the Scorpaenidae family. It is sometimes refer to as the "idiot fish" or "idiot cod" due to its large oversize head/eyes. It is found in Canada
, Russia
, and the United States
. Adult S. alascanus live predominantly in the oxygen minimum zone
(OMZ), and thus require specific adaptations/exaptations in order to overcome the problems posed by the extremely low levels of oxygen saturation. Allowing for an increased ventilation frequency during exposure to progressively hypoxic
conditions, as compared to its more shallow relative Scorpaena guttata, enables S. alascanus to compensate for the inherent low concentrations of oxygen in the OMZ. Further, heightened levels of lactate dehydrogenase
, specifically the anaerobic isoform- LDH-A in the heart and muscles of S. alascanus, suggests an adaptive mechanism for ATP
production during low oxygen availability.
Fish
Fish are a paraphyletic group of organisms that consist of all gill-bearing aquatic vertebrate animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish, as well as various extinct related groups...
in the Scorpaenidae family. It is sometimes refer to as the "idiot fish" or "idiot cod" due to its large oversize head/eyes. It is found in Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
, Russia
Russia
Russia or , officially known as both Russia and the Russian Federation , is a country in northern Eurasia. It is a federal semi-presidential republic, comprising 83 federal subjects...
, and the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
. Adult S. alascanus live predominantly in the oxygen minimum zone
Oxygen minimum zone
The Oxygen minimum zone , sometimes referred to as the shadow zone, is the zone in which oxygen saturation in seawater in the ocean is at its lowest. This zone occurs at depths of about 200 to 1,000 metres, depending on local circumstances....
(OMZ), and thus require specific adaptations/exaptations in order to overcome the problems posed by the extremely low levels of oxygen saturation. Allowing for an increased ventilation frequency during exposure to progressively hypoxic
Hypoxia (medical)
Hypoxia, or hypoxiation, is a pathological condition in which the body as a whole or a region of the body is deprived of adequate oxygen supply. Variations in arterial oxygen concentrations can be part of the normal physiology, for example, during strenuous physical exercise...
conditions, as compared to its more shallow relative Scorpaena guttata, enables S. alascanus to compensate for the inherent low concentrations of oxygen in the OMZ. Further, heightened levels of lactate dehydrogenase
Lactate dehydrogenase
Lactate dehydrogenase is an enzyme present in a wide variety of organisms, including plants and animals.Lactate dehydrogenases exist in four distinct enzyme classes. Two of them are cytochrome c-dependent enzymes, each acting on either D-lactate or L-lactate...
, specifically the anaerobic isoform- LDH-A in the heart and muscles of S. alascanus, suggests an adaptive mechanism for ATP
Adenosine triphosphate
Adenosine-5'-triphosphate is a multifunctional nucleoside triphosphate used in cells as a coenzyme. It is often called the "molecular unit of currency" of intracellular energy transfer. ATP transports chemical energy within cells for metabolism...
production during low oxygen availability.
Source
- Bell, T. & Guttman, A. 2000. Sebastolobus alascanus. 2006 IUCN Red List of Threatened Species. Downloaded on 5 August 2007.
- Yang, et al. (1992). "Respiratory, Blood, and Heart Enzymatic Adaptations of Sebastolobus alascanus (Scorpaenidae; Teleosti) to the Oxygen Minimum Zone: A Comparative Study". Biological Bulletin 183: 490-499. http://www.biolbull.org/cgi/reprint/183/3/490.pdf