CLASSIFICATION OF CLATHRINA OR OLYNTHUS
Distributed from Matha’s vineyard to Gulf of St. Lawrence. From Casco bay to Arctic ocean and common in Europe.
HABIT AND HABITAT
Clathrina is a simple, marine sponge attached to rocks or substratum.
GENERAL CHARACTERSTICS OF CLATHRINA OR OLYNTHUS
- Originally it was presumed as adult and was called as Olynthus, but now it is known to represent the late developmental stage of some sponge.
- Sedentary sponge with a free end containing osculum.
- Spongocoel opens through the osculum.
- Body is cylindrical and perforated by various ostia.
- The skeleton contains spicules in the form of triactines and/or tetractines, sometimes with diactines, tripods and tetrapods as well.
- Development is complicated.
- The choanoderm is usually flat, never forming folds when the sponge is extended.
The animal has broad anterior, portion with osculum, ostia and narrow posterior portion attached to substratum and all above characters, hence it is Clathrina.