Copromyxa microcystidis
C. microcystidis - from Van Wichelen et al., 2016

 

 

Copromyxa microcystidis Van Wichelen et Vanormelingen, 2016

 

Diagnosis: Locomotive amoebae limax-shaped, 20– 59 µm long and 7–17 µm wide with anteriorly a well pronounced hyaline cap. Monopodial movement eruptive-like by means of alternating lateral sprouting lobes regularly adopting a bipodial or multipodial state. Vesicular oval nucleus of 5–10 µm in diameter with one central to slightly eccentrically placed globular nucleolus. Usually one, rarely up to 3 small contractile vacuoles present posteriorly. The cytoplasm always contains up to 22 opaque crystals and several smaller, refractive spheres. Floating form spherical with a diameter of 15–20 µm and radially displaying up to 10 small hyaline lobes. Cysts spherical with a diameter of maximally 20 µm.

 

Ecology: Freshwater. It feeds voraciously on Microcystis aeruginosa. Other Microcystis morphotypes (M. viridis, M. wesenbergii), heterotrophic bacteria and green algae (Acutodesmus) were not ingested (Van Wichelen, unpublished).