Regions of the Earth directly adjacent to the tropics. The warmest portions of the temperate zones.

Marked with parallel grooves or furrows.

An additional tank connected to the display aquarium normally used to house filter media and other equipment.

Of or relating to the area above the eye.

In biology, located above or higher than.

Mouth opening upwards due to the lower jaw projecting anteriorly further than the upper.

Between the side and upper surface. Same meaning as dorsolateral.

Above the gills.

Of, relating to, or being the supraoccipital bone, a median bone in the upper rear part of the skull.

Above the eye.

Located above the eye.

Part of the lateral line system extending up and over the eye.

Thin film forming at the water surface due to surface tension.

Property of liquids caused by intermolecular forces with the result that the surface acts as a thin, flexible film able to withstand a degree of force thus allowing certain objects to float on it, for example.

Any structure suspending or holding up another, especially the series of cartilage and bone suspending the lower jaw from the skull.

Low-lying, uncultivated wetland dominated by woody vegetation.

See gas bladder.

Close, long-term association between two different biological species. Often obligatory and often, though not always, with a mutual benefit for both organisms.

Occurring within the same, specified geographical area, but without interbreeding and not necessarily competing for the same resources or dwelling in the same habitat. Opposite of allopatric.

Swelling located at the tip of the lower jaw in some fish species.