noun
- a simple sponge with a tubular or vase-like body and a single opening (osculum) at the top
Usage: biology; zoology
Examples
- The ascon is the most primitive body form found among sponges.
- In an ascon sponge, water enters through small pores and exits through the central osculum.
- Marine biologists study ascon sponges to understand early sponge evolution.
- The ascon structure consists of a simple wall with choanocytes lining the interior cavity.