Results for “species”

extinct

Of a species or other taxonomic grouping, having no living members; no longer in existence.

Used in 22 profiles

extirpate

To destroy completely; to exterminate. Sometimes applied to cases where a species is extinct in one country or area but extant in others.

F1

Term used in the fields of genetics and selective breeding in reference to the first filial generation, i.e., hybrid offpsring, of a cross between two distinctly different parental lines. Often used in aquarium literature to refer to offspring of F0 parents whether of the same species or not.

feeder fish

Live fish used specifically for feeding to another fish.

Used in 126 profiles

filter feeding

Feeding behaviour in which solid, organic particles are filtered from the surrounding water. Normally involves some degree of specialised morphology.

Used in 1 profile

fin-spine

Unsegmented and unbranched, bony structure supporting the fins in teleosts. Usually hard, rigid and pointed and may have a smooth or serrated edge. Not laterally-paired like rays, and in some species modified to form a protective structure.

Used in 15 profiles

fishery

Specified area or region in which fish are caught or collected; place where fishes are reared.

Used in 25 profiles

floating meadow

Floating tangle of plants comprising one or more species. Important habitat for many freshwater fishes in certain biotopes.

Used in 3 profiles

fork length

Length of a fish specimen measured from the tip of the snout to the end of the medial caudal fin rays, i.e., the deepest point of the 'fork' formed by the fin. Tends not to be used in systematics.

formalin

Aqueous solution of formaldehyde used as a preservative for biological specimens.

fractional spawner

A fish species in which females release eggs at intervals over a given period.

Used in 21 profiles

gas bladder

Gas-filled sac with 1-3 chambers, situated just below the vertebral column in most ray-finned fishes. Its primary function is to aid in buoyancy by offsetting the weight of heavier structures such as bone, but is also used for respiration or sound production in some species. Often reduced in benthic fishes and sometimes absent altogether. Also known as the air or swim bladder.

Used in 104 profiles

Gastropoda

Class of molluscs of which the majority of members possess a flattened, muscular foot for locomotion and a head bearing specialised sensory tentacles, with some also having a univalve, coiled shell. Includes all snails, whelks, limpets, conches, and slugs.

genetics

Branch of biology concerned with the study of heredity and variation of organisms; the genetic constitution of a single organism, species, or other taxonomic group.

Used in 4 profiles

Gram's method

Method of differentiating bacterial species into groups based on the structure of their cell walls, using a particular, violet-coloured, staining technique.

grindal worm

Vernacular name for the annelid worm Enchytraeus buchholzi (Vejdovsky, 1879), a species commonly cultured by aquarists for use as live fish food. Smaller, more adaptable, and temperature-tolerant than the related white worm, Enchytraeus albidus Henle, 1937.

Used in 78 profiles

guanine

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

heterospecific

Of or belonging to a different species.

Used in 18 profiles

Hexamita

Genus of parasitic flagellates, some species of which inhabit the intestines of fishes. May cause head and lateral line erosion.

hierarchy

Series of ordered or groupings or rankings within a defined system. Taxonomy is a form of hierarchy as are the ranked social groupings typical of certain fish species. The latter form of social hierarchy is also known as a pecking order.

Used in 85 profiles