Blotch-like marking extending over the dorsal surface in certain fishes. Highly variable in number and form depending on taxon, and often used as an identifying feature.

A solution containing dissolved salts.

General term for the salt concentration of water.

Treatment against various parasites which involves placing a freshwater fish in a solution of saline water with the salt concentration and period of exposure variable depending on the size of the fish and severity of infection. Similar to a salt dip in that parasites are killed via osmotic shock, but of longer duration.

In ichthyology, a collection of fishes made from a particular locality or specified area.

Fine-grained silicate material commonly used as substrate. Often but not always chemically inert, and can therefore be used as a buffer.

Genus of aquatic fungi, some species of which attack fishes. Normally a secondary pathogen attacking previously damaged tissue and causing cellular necrosis alongside other epidermal damage. Generally visible as a whitish or greyish filamentous fungus and thus commonly referred to as cotton-wool disease.

Feeding on dead or decaying organic matter.

Feeding on flesh.

Type of grassland ecosystem characterised by any trees present being spaced in such a way that they do not form a closed canopy, thus sufficient light reaches the ground to support unbroken herbaceous cover consisting primarily of grasses. Also spelled ‘savannah’.

See squamation.

Dermal, plate-like structure covering the body in many fishes.

Count of a given range of scales. Used in taxonomical studies to differentiate and identify taxa.

Covered in or resembling scales.

A Weberian ossicle.

Paired bone attached to the pterygials, actinosts or radials of the pectoral fin. Articulates ventrally with the coracoid and anteriorly with the cleithrum.

Animal feeding on dead or decaying organic matter.

Tightly-aggregated group of fishes, normally of the same species, which tends to orient and move in the same direction; the act of schooling. Often confused with shoal.

Behaviour exhibited by members of a school in which individuals move in a coordinated manner in the same direction.

Formal binomial or trinomial name of a species used in zoological nomenclature.