Micrasterias papilliferaImage © Henk Schulp

Cell of Micrasterias papillifera. Notice the apical lobes which are distinctly dilated from the base towards the apex.

Cell dimensions (L x B): ca 160 x 140 µm

 


Desmid of the month
July 2005

Micrasterias papillifera

Superficially, Micrasterias papilliferea somewhat resembles M. rotata but cells are smaller and the apical lobes are more dilating. Its name is derived from the fact that the denticulations of the highest order lobules often are somewhat swollen (papillate) by pore-secreted material. As compared with other Micrasterias species M. papillifera is relatively frequently encountered in sporulating condition. In the Netherlands M. papillifera has increased in the last decades (e.g., Coesel 2001). It is of occasional occurrence in slightly acidic, mesotrophic moorland pools, peat pits and fen hollows.

Reference

Coesel, P., 2001. Flagship desmid species in newly excavated peat holes at Ankeveen  (in Dutch with summary in English). — De Levende Natuur 102: 123-129.

another cellImage © Henk Schulp

Cell of M. papillifera in which the marginal denticulations are papillate by accumulation of secretion products.

Micrasterias papillifera, secretieImage © Matthijs Koek

Cell of M. papillifera (var. pseudomurrayi) pushing off drops of secreted material.

Micrasterias papillifera
Image © Wim van Egmond

Zygospore of M. papillifera with adhering empty gametangial cells. Like in many other Micrasterias species the zygospore is globose and furnished with long, usually furcate spines.