''Walkeria tuberosa'' is a species of

colonial Colonial or The Colonial may refer to: * Colonial, of, relating to, or characteristic of a colony or colony (biology) Architecture * American colonial architecture * French Colonial * Spanish Colonial architecture Automobiles * Colonial (1920 a ...

bryozoan in the

order Order, ORDER or Orders may refer to: * Categorization, the process in which ideas and objects are recognized, differentiated, and understood * Heterarchy, a system of organization wherein the elements have the potential to be ranked a number of d ...

Ctenostomatida. It is native to the Mediterranean Sea, and has spread to the Red Sea and the Indo-Pacific region. This species was first described in 1867 by the Austrian zoologist Camill Heller, and was named in honour of the Scottish minister and natural historian John Walker, a professor at the University of Edinburgh. There is some confusion as to whether the original scientific name of the bryozoan was ''Walkeria tuberosa'' or ''Valkeria tuberosa''. The genus name '' Walkeria'' was in 1994 given to a genus of dinosaurs, in this case being in honour of the British palaeontologist Alick Walker. When it was realised that the name had previously been used and was therefore not available, the dinosaurs were renamed '' Alwalkeria''.

Description

''Walkeria tuberosa'' is a colonial bryozoan and forms small clusters developing from a thread-like stolon that creeps across the

substrate Substrate may refer to: Physical layers *Substrate (biology), the natural environment in which an organism lives, or the surface or medium on which an organism grows or is attached ** Substrate (locomotion), the surface over which an organism lo ...

. The zooids are vase-shaped and grow in groups direct from the stolon and not from each other. Each zooid is about long and tipped by a relatively long lophophore with a crown of eight tentacles. The clusters of zooids are about apart. The colony is light beige or pale grey.

Distribution and habitat

''Walkeria tuberosa'' was first described from the Adriatic Sea and is also found in the western, central and eastern Mediterranean, including between Crete and Turkey. It is also sporadically found in the Red Sea and the Indo-Pacific region, including Malaysia and New Zealand. It occurs from the lower littoral zone down to about . It grows on rocks and other hard substrates as well as on the thallus of algae. When the tufts of zooids grow among a crowded community of other organisms, its presence is very difficult to detect, but where it grows alone, on an otherwise bare surface, it is easier to spot; such a surface might be a thallus of red alga such as ''

Peyssonnelia ''Peyssonnelia'' is a genus of thalloid red alga, named after naturalist Jean-André Peyssonnel (1694–1759) It includes the algae commonly known as rumoi-iwanokawa, mayoi-iwanokawa and akase-iwanokawa. Specimens can reach around 20 cm in ...

'' sp., of a green alga such as '' Codium'' sp. or ''

Flabellia ''Flabellia'' is a genus of green algae in the family Halimedaceae. ''Flabellaria'' is an accepted synonym of this genus. It is a monotypic genus and ''Flabellia petiolata'' is the only species; it is found in the eastern Atlantic Ocean and the M ...

'' sp., or a colonial tunicate such as '' Aplidium undulatum''.

References

{{Taxonbar, from=Q4179941 Ctenostomatida Fauna of the Mediterranean Sea Animals described in 1867