Les straménopiles (Stramenopila : « organismes plumeux », ou hétérokontes — Heterokonta : « organismes à deux flagelles différents ») constituent un sous-règne des eucaryotes.

Ils sont caractérisés par l'existence, au cours de leur cycle, d'une cellule biflagellée avec deux flagelles différents : un flagelle lisse est un flagelle plumeux à mastigonèmes tubulaires tripartites.

Certains, comme les diatomées, étaient autrefois classés dans les algues, d'autres, comme les oomycètes, étaient autrefois classés dans les champignons, d'autres encore étaient classés dans les protistes.

[modifier] Taxons de rang inférieur

Groupes hétérotrophes
- Blastocystae
- Proeromonadea
- Opalinidea
- Bicoecea
- Labyrinthulomycetes
- Oomycetes
- Hyphochytridiomycetes
- Bigyromonadea
Groupes autotrophes (Ochrophyta)
- Pinguiophyceae
- Bacillariophyta
- Bolidophyceae
- Parmophyceae
- Pelagophyceae s.l.
- Pedillenophyceae s.l.
- Raphidophyceae
- Phaeothamniophyceae
- Chrysomerophyceae
- Xanthophyceae
- Schizocladiophyceae
- Phaeophyceae
- Eustigmatophyceae
- Chrysophyceae

[modifier] Etymologie

L'origine du terme straménopile est explicitée dans le passage suivant de Adl et al. (2005)<ref>Adl, S. M. et al. (2005). "The new higher level classification of eukaryotes with emphasis on the taxonomy of protists. Journal of Eukaryotic Microbiology 52: 399-451.</ref> :

"Regarding the spelling of stramenopile, it was originally spelled stramenopile. The Latin word for ‘‘straw’’ is stramine-us, -a, -um, adj. [stramen], made of straw—thus, it should have been spelled straminopile. However, Patterson (1989)<ref>Patterson, D. J. (1999). The diversity of eukaryotes. American Naturalist 154: S96-S124</ref> clearly stated that this is a common name (hence, lower case, not capitalized) and as a common name, it can be spelled as Patterson chooses. If he had stipulated that the name was a formal name, governed by rules of nomenclature, then his spelling would have been an orthogonal mutation and one would simply correct the spelling in subsequent publications (e.g. Straminopiles). But, it was not Patterson’s desire to use the term in a formal sense. Thus, if we use it in a formal sense, it must be formally described (and in addition, in Latin, if it is to be used botanically). However, and here is the strange part of this, many people liked the name, but wanted it to be used formally. So they capitalized the ﬁrst letter, and made it Stramenopiles; others corrected the Latin spelling to Straminopiles."