The inability of two or more groups of organisms to interbreed due to the existence of geographical, behavioral, physiological, or genetic barriers. These can be further separated into those being active pre- or post-copulation.

Natural or artificial pond, lake or tank used for the collection and storage of water.

Form of niche differentiation by which two species partition (divide) a resource based on behavioral or morphological variation in order to ensure their mutual survival by reducing competition.

The process by which an organism acquires the oxygen necessary for metabolism and expels excess carbon dioxide formed during energy-yielding reactions.

Resembling a network or net, or having a network of parts, as seen in the colour pattern of many fishes.

Constructed, arranged, or marked like a net or network; having a reticulate pattern consisting of interconnected lines.

Arrangement or pattern in the form of a network or net.

Directed or curved backwards or inwards; opposite of atrose.

Form of purification, often abbreviated to RO, that removes dissolved salts and other impurities from water by applying pressure to it on one side of a semipermeable membrane. Pure water molecules are able to pass through the membrane while the majority of others are not, with more-or-less pure water the result. Sometimes used in combination with […]

Device used to purify water via the process of reverse osmosis. Some units combine both reverse osomosis and deionisation functions.

In taxonomy,  a paper or study concerned with changes, amendments or corrections to a particular taxonomic group.

An organism living or thriving in running water.

See rheophile.

Living or thriving in running water.

Movement or orientation of an organism towards, into (positive rheotaxis) or away from (negative rheotaxis) a current of air or water

Rootlike, filamentous structure used for attachment to a substrate and uptake of nutrients in mosses,  ferns, and related plants, plus certain algae and fungi.

Of or relating to a rhizoid or rhizoid-bearing organism.

Horizontally-orientated plant stem growing under or along the ground surface from which new roots and shoots often arise.

Division of eukaryotic algae containing thousands of species, most of which are multicellular and inhabit marine environments, e.g., many seaweeds.

Parallelogram with adjacent sides of unequal lengths; shaped like a rhombus or rhomboid.