''Tetilla'' is a genus of

demosponge Demosponges (Demospongiae) are the most diverse class in the phylum Porifera. They include 76.2% of all species of sponges with nearly 8,800 species worldwide (World Porifera Database). They are sponges with a soft body that covers a har ...

s in the family

Tetillidae Tetillidae is a family of marine sponges. Tetillids are more or less spherical sponges (sometimes referred to as golf ball sponges) which are found commonly in all marine habitats at all depths throughout the world. They are especially common in ...

. It is widely distributed. They are mainly found in deeper habitats.

Description

These globular sponges lack porocalices (special pore bearing pits) and auxiliary megascleres. The surface is covered with conical elevations (conules) or uniformly covered in minute spines. They have few oscules. These are typically located at the top. Spicule strands at the base act as a root system, attaching the sponge to the substrate. There is no visible cortex when a cross-section is taken. The spirally radiate skeleton is made of bundles of oxeas (needle-shaped

spicules Spicules are any of various small needle-like anatomical structures occurring in organisms Spicule may also refer to: *Spicule (sponge), small skeletal elements of sea sponges *Spicule (nematode), reproductive structures found in male nematodes ( ...

) originating from the center of the sponge. These become mixed with triaenes (elongated spicules with three rays at one end), mainly protriaenes. The microscleres are sigmaspires (a spirally twisted s-shaped spicule). These are absent in the type species ('' T. euplocamos'').

Species

The following species are recognised:

References

{{Taxonbar, from=Q3385410 Demospongiae Sponge genera