| 词条 | Celatheca |
| 释义 |
| name = Celatheca | fossil_range = {{Geological range/linked|Early Devonian}} | image = | image_caption = | regnum = Plantae | subregnum = Embryophyta | genus = †Celatheca | genus_authority = S.G.Hao & Gensel (1995) | subdivision_ranks = Species | subdivision ={{Species list |C. beckii|S.G.Hao & Gensel (1995) }}Celatheca is a genus of extinct plants of the Early Devonian (Pragian, around {{Period span/brief|Pragian|-1}}). Fossils were first found in the Posongchong Formation of eastern Yunnan, China. The leafless stems (axes) divided dichotomously but unequally so that one branch formed more of a 'main' stem and the other a side branch system. Side branches which did not bear spore-forming organs or sporangia divided two or three times further, ending in tips which curled back on themselves. Side branches bearing sporangia ultimately divided to produce a group of four sporangia, each with an outer leaf-like bract which folded around the sporangium. Celatheca resembles the Australian fossil Yarravia. References}}{{Taxonbar|from=Q5057538}}{{paleobotany-stub}} 1 : Early Devonian plants |
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