: a genus of Carboniferous seed ferns exhibiting features in common with the genera Lyginopteris and Heterangium and being of special interest because of the evidence it provides concerning the origin of seed plants from the Psilophytales

Word History


New Latin, from micr- + sperm- + -pteris

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Dictionary Entries Near Microspermopteris

Cite this Entry

“Microspermopteris.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Microspermopteris. Accessed 25 Apr. 2024.

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