{{Short description|Extinct order of algae}} {{Automatic taxobox |fossil_range={{Geological range|Silurian|Carboniferous}} |taxon = Sycidiales |subdivision_ranks = Families |subdivision = See text. }} '''Sycidiales''' is an order of fossil charophyte green algae.<ref name=AB_t179954>{{AlgaeBase taxon |mode=cs2 |name=Sycidiales |id=179954 |access-date=2022-02-20}}</ref> The reproductive structures in Sycidales have a calcified cover, called a ''utricle'', that is thought to prevent the zygote being desiccated. Other Paleozoic families lack this cover, as do modern charophytes. Fossils of the family Sycidiaceae are found over the longest time span, from the Silurian to the Carboniferous.<ref name=TaylTaylKrin09>{{Citation |last1=Taylor |first1=T.N. |last2=Taylor |first2=E.L. |last3=Krings |first3=M. |year=2009 |title=Paleobotany, The Biology and Evolution of Fossil Plants |edition=2nd |publication-place=Amsterdam; Boston |publisher=Academic Press |isbn=978-0-12-373972-8 |name-list-style=amp |pages=136–137 }}</ref>
==Families and genera== {{As of|2022|February}}, AlgaeBase accepted the following families<ref name=AB_t179954/> and genera.<ref>{{AlgaeBase taxon |mode=cs2 |name=Chovanellaceae |id=179956 |access-date=2022-02-20}}</ref><ref>{{AlgaeBase taxon |mode=cs2 |name=Sycidiaceae |id=179957 |access-date=2022-02-20}}</ref> *†Chovanellaceae **†''Chovanella'' <small>Reitlinger & Yartseva</small> – 1 species *†Sycidiaceae <small>Karpinsky</small> **†''Calcisphaera'' <small>Williamson</small> – 4 species **†''Gemmichara'' <small>Zhen Wang</small> – 1 species **†''Maslovella'' <small>Samojlova</small> – 1 species **†''Sycidium'' <small>G.Sandberger</small> – 12 species
==References== {{Reflist}}
{{taxonbar|from1=Q35137047}}
Category:Charophyta Category:Charophyta orders {{Green alga-stub}}