Ichthyological terms, not general ones.
Natural, ecological process in which organic material is broken down into simpler substances which may then be used by other organisms. Typically biotic and carried out by microbes, worms, and other organisms but can also be abiotic and occur via chemical or physical processes such as oxidation or hydrolysis.
Used in 204 profiles
Living, occurring close to, deposited or sinking onto the bottom of a water body.
Used in 5 profiles
In biology, the occurrence within a species of two forms which differ distinctly from one another in one or more characters, e.g., colour pattern or morphology.
Used in 2 profiles
Type of stream or river that branches off and flows away from a main channel. Particularly common in river deltas, but also occur inland in some cases.
Used in 2 profiles
Of, relating to, or occuring during daylight hours; having a daily cycle. Opposite of nocturnal.
Used in 6 profiles
Accumulation of fluid in cellular tissue or other body cavity, symptomatic of some underlying infection or other health issue but not a disease in itself. May also be referred to as 'oedema' or 'edema'.
Study of the interactions occurring between organisms and their environments; also used to refer directly to such relationships.
Used in 18 profiles
A distinct population of a species adapted to occupy a particular habitat due to localised natural selection.
Abnormal bulging of the eye from the orbit commonly referred to as 'pop eye' in aquarium literature and resulting from excessive accumulation of fluid or gases at the back of the socket. Not a disease but a secondary sympom of some other infection or physical issue.
A species occurring outside its known natural range, most often due to accidental or intentional dispersal by human activities. Also referred to as introduced or alien species.
Used in 19 profiles
In biology, Darwinian fitness or simply fitness of a biological trait describes how successful an organism has been at passing on its genes. The more likely that an individual is able to survive and live longer to reproduce, the higher is the fitness of that individual.
Large genus of amphipod crustacean in the family Gammaridae of which members occur in both fresh and salt water. An important source of food for many fishes.
Used in 2 profiles
Basic hereditary unit comprising a sequence of nuceleotides within a strand of DNA or RNA and occupying a fixed position on a chromosome. Generally determines a particular character or trait present in an organism by directing production and activity of RNA.
Used in 10 profiles
An account of the direct descent of an individual or group from an ancestor; study or investigation of the evolutionary development of an organism(s) from older, related forms; a record, chart, or table depicting a pattern of descent.
Crystalline chemical compound giving a metallic, iridescent golden, silvery, white, blue or greenish sheen to the scales of certain fishes. Occurs naturally in some fish species but in others its formation is driven by parasitic infection.
Used in 4 profiles
Severe physical condition relatively common to certain fishes in captivity and also known as hole-in-the-head. Sometimes attributed to protozoan parasites of the genus Hexamita or an autoimmune disorder though these theories remains unconfirmed. Certainly associated with and exacerbated by poor water quality and/or nutrition, however. Initially manifests itself as small lesions, normally on the head of an affected individual, but may also extend along the lateral line and into the unpaired fins. If left unchecked these lesions can develop into larger, whitish pits and the condition may prove fatal. Often abbreviated to HLLE and similar to, but not analagous with, neuromastic pitting. Does not appear to occur in nature.
Used in 35 profiles
Instrument used to measure the density of a liquid, normally in the form of specific gravity. Can be inaccurate should calcium deposits form on the swing arm, for example, and generally less reliable than a refractometer.
Printed or computer-aided table or other device assisting identification of species. Normally presented in the form of a single-access key.
Used in 4 profiles
A body of water, such as a reservoir, formed by artificially-aided accumulation and storage.
Used in 11 profiles
Produced, growing, living, or occurring naturally in a given region, country, or environment
Used in 6 profiles