Arabic term used to refer to a valley, stream-bed or other watercourse that only holds water during the rainy season. Often associated with oases and normally applied only in certain Arabic-speaking countries.
Glossary: Wallace’s line
Hypothetical line, proposed by British naturalist Alfred Russel Wallace that marks the transitional boundary between the Oriental and Australian zoogeographical regions. It passes between the islands of Borneo and Sulawesi to its northern limit, Bali and Lombok to the south. To the west of the line organisms descended from Asiatic ancestors predominate, while to the […]
Glossary: warm water
Used in reference to water bodies with a temperature that exceeds 75.2Â°C/24Â°C during the summer.
Glossary: water column
Conceptual column representing the vertical section of a water body from surface to substrate.
Glossary: water table
The point below which the ground is saturated with water.
A natural or artificial channel through which water flows; a stream or river.
An ridge or otherwise elevated piece of land that physically separates areas drained by different river systems. Also used to refer to an area or region drained by a particular river, river system, or other water body.
Glossary: wave maker
Electrical, often programmable, timing device that alternates power supply to multiple, submerged powerheads at predetermined time intervals. Most often used in marine aquaria to simulate natural wave action.
Glossary: Weberian apparatus
Anatomical structure connecting the swim bladder to the inner ear found in members of the fish superorder Ostariophysi. Conveys sound and changes in pressure, and comprises four or five modified vertebrae.
Glossary: Weberian ossicle
Any of the modified vertebrae comprising the Weberian apparatus in Ostariophysian fishes, individually named the claustrum, scaphium, intercalarium and tripus.
Glossary: Weberian vertebra
See Weberian ossicle.
Low dam constructed across a river to raise the water level, divert the water, or control its flow; series of traps or enclosures designed to catch fishes.
Glossary: Western Ghats
Mountain range extending southwards down the western side of India from the borders of Gujarat and Maharashtra states, through Maharashtra, Goa, Karnataka, Tamil Nadu and Kerala as far as Kanyakumari district in Tamil Nadu. The Ghats are a UNESCO World Heritage Site and represent one of the eight hottest hotspots of biological diversity in the […]
Glossary: wet/dry filter
Type of filter normally placed under the aquarium, and often home-made. The basic premise is that water trickles vertically downards through separated compartments containing mechanical and biological filter media with spaces inbetween so that it is also exposed to the air briefly. It then collects in a base chamber or sump from where it is […]
Area of ground saturated with, normally shallow, fresh, salt or brackish water on a permanent or seasonal basis, e.g., marshes, bogs, swamps.
Glossary: white spot
Glossary: white worm
Vernacular name for the annelid worm Enchytraeus albidus Henle, 1937, a species commonly cultured by aquarists for use as live fish food.
Collective term for the young of various fishes, especially herring and sprat. Sometimes used as food for predatory species in aquaria.
In ichthyological and aquarium literature typically refers to habitats with turbid water containing material in suspension and often rich in nutrients and dissolved ions, thus differing from clearwater or blackwater environments. Not to be confused with the term ‘white water’ which refers to turbulent water typically formed in rapids.
In reference to aquarium fishes, caught in the natural habitat; not bred in captivity.