词条 | Christensenia (plant) |
释义 |
For the broad-nosed weevil genus, see Christensenia (beetle).{{Automatic taxobox | taxon = Christensenia (plant) | authority = Maxon | synonyms =Kaulfussia C.Presl }} Christensenia is a genus of ferns in the botanical family Marattiaceae. The genus is confined to the Indo-Malayan region. The basal chromosome number for this genus is 2n=80. Christensenia is unique in the Marattiaceae, because of its reticulate venation, palmately arranged leaves and radial synangia. Christensenia produces enormous amounts of spores, up to 7,000 spores per sporangium. The presence of a radial synangium is an archaic character, very similar to some of the fossil Asterothecaceae/Psaroniaceae, such as Scolecopteris. Christensenia itself has no fossil record. SpeciesAfter the 1993 revision by Rolleri, only two species and one variety are recognized:
References
1 : Marattiopsida |
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