Glossary terms starting with "m"

Mantle

The downturned side of the valve surrounding the valve face. When a frustule is viewed in girdle view, the mantle is visible.

Monoraphid

Pennate diatoms having a raphe on only one valve. A monoraphid diatom is a type of heterovalvar diatom. Example genera include Cocconeis, Achnanthidium, and Eucocconeis.

During the ontogeny of monorahid diatoms, a raphe begins to form on each valve. One valve completes its raphe, and becomes the raphe valve. The other valve fills its incipient raphe with silica, leaving a thickened axial rib, and becomes the rapheless valve.

The genus Nupela includes some monoraphid species and some biraphid species. In this web flora, Nupela is included in the biraphid group.

Monotypic

A genus with a single, validly published binomial. An example of a monotypic genus is Diprora Main, which contains only the species D. haenaensis Main.

 

Mucopolysaccharide

A polysaccharide built of amino sugars and often associated with proteins. Secreted from a variety of openings in the diatom frustule. Mucopolysaccharides can be components of mucilage, a complex colloidal material used by diatoms for movement, protection, and adhesion.