anadromous
Migrating from marine to freshwater environments in order to spawn, as many salmonids do for example.
Results for “sp.”
Ichthyological terms, not general ones.
andropodium
Modified, flexible anal fin rays present in males of some fish species (families Hemirhamphidae and Goodeidae) giving the fin a 'notched' appearance. Not used for insemination like the gonopodium in members of the family Poecillidae but to clasp the female during mating.
Used in 5 profiles
annual fish
A fish species which naturally completes its life cycle within a year at the end of which it dies leaving behind fertile eggs which typically survive in the soil and hatch during the next rainy season. Often used in reference to certain South American and African killifishes.
Used in 4 profiles
apical
Refers to the tip or cusp of an oral tooth, or denotes orientation towards the apex or tip of a fin, fin-spine, etc..
apomorphy
A derived character state of a clade; a feature novel to a species and its descendants.
Used in 2 profiles
aquifer
A subterranean bed or layer of permeable rock, sediment or soil that bears water. Naturally-occuring springs and wells are fed by aquifers.
asexual reproduction
Mode of reproduction which does not involve fertilisation whereby offspring derive from a single parent and inherit genes only from that parent. Known in the Amazon Molly, Poecilia formosa, and some other fish species.
atypical
Not conforming to type; an abnormal specimen.
Used in 1 profile
Bacillus
Genus of Gram-positive, mostly rod-shaped, bacteria including both free-living and pathogenic species.
beel
Term used in India and Bangladesh to describe a low lying, water-filled depression on a floodplain, sometimes becoming dessicated during the dry season. Also spelled 'bheel'.
Used in 4 profiles
benthopelagic
Used in reference to fish species living or feeding at or near the bottom of a water body. Some of these may also do so in the midwater or surface levels.
Used in 1 profile
bifurcate
Split or divided into two forks or branches.
Used in 14 profiles
binomial nomenclature
The scientific system of naming an organism using two terms, the first representing the genus and the second the species. Also referred to as 'scientific name' or, somewhat inaccurately, 'Latin name'.
biofilter
Pollution control technique employing living matter to capture and biologically degrade potential pollutants. Aquarium biofilters tend to contain a medium with a large specific surface area (SSA) favouring colonisation by billions of beneficial microorganisms.
Used in 6 profiles
biogeography
Study of the geographic distribution of plants, animals and ecosystems in both space and geological time.
Used in 13 profiles
blackwater
In ichthyological and aquarium literature typically refers to water rich in humic acids and poor in nutrients such as that associated with ancient peat swamps or parts of the Amazon river drainage, and thus differs from clearwater and whitewater. Fish species inhabiting such environments typically require similar conditions in captivity, especially if wild caught.
Used in 169 profiles
bloodworm
The freshwater larvae of certain midges which appear bright red due to their high haemoglobin content. Some species of the non-biting Chironomidae family are produced commerically for fish food with the larvae frozen or freeze-dried.
Used in 1,068 profiles
branchiostegal membrane
The membrane, sometimes referred to as the gill membrane, connecting the branchiostegal rays and enclosing the ventral portion of the branchial cavity. Normally extended when the opercle of a fish is open, sealing the branchial cavity and creating a vacuum in the mouth, and also used during threat, courtship and other communicative behaviours in many species.
Used in 5 profiles
breeding cycle
In fishes, the period of time between hatching and first spawning within a particular generataion.
Used in 3 profiles
breeding line
A group of identical, pure-breeding diploid or polyploid organisms, distinguished from others of the same species by a unique phenotype and genotype. Important in production of line breeding ornamental fish strains.