Based on your selection, the specimen is a type of algae. Continue with the key below to determine which taxonomic group it belongs to, or click here to learn more about algae as a whole.

 

Select the option that best describes your specimen:

Cell(s) with a glass-like external covering, (usually) patterned with lines. Plastids golden or golden-brown. Cell(s) solitary, or in chains/filaments, or in ribbon-like, zigzag, star-like, or other kinds of colonies. No flagella; not free-swimming. Non-motile or motile; if motile, cell moves by gliding/creeping along surfaces.

Cell(s) not as described to the left.

Glossary Terms on This Page

Plastid: In general, a plastid is a special type of organelle. Many of these organelles contain photosynthetic pigments; a chloroplast is one example of a plastid. Here, we use this term mainly when discussing diatoms, because the word “plastid” is typically used in place of “chloroplast” when referring to diatoms.