juvenile trophont

Description:

Clathrulina, one of the desmothoracid protists. Traditionally classified as the heliozoa because of the star-shaped appearance of the cell, but the heliozoa have always been a rag-bag of unrelated organisms. Desmothoracids may adopt one of several forms. A ‘mature’ trophont (feeding form) is an amoeboid organism with stiffened arms. It lives in an spherical (ish) organic lorica which has large openings. The chamber is borned on a hollow stalk, and several stalked loricae may be joined end to end or in a branching arrangement. The stiffened pseudopodia extend out of the openings to capture food. Division leads to the formation of flagellated cells one or all progeny vacate the lorica, swim around and then settle as an amoeba. The amoeba secrete a stalk and mucus, and the mucus is shaped and accretes to form a lorica. The lorica strengthens and thickens with age. This image is of a young cell that is part way through the process of creating a lorica. Differential interference contrast.Phase contrast micrograph.