The Natural History of Model Organisms: The biology of C. richardii as a tool to understand plant evolution
Figures
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Cartoon phylogeny of land plants.
Within the Polypodiopsida (ferns), the estimated number of genera and species (genera/species) are noted for each major group. Black stars show the three extant independent evolutions of heterospory (Bateman and DiMichele, 1994). In the family Pteridaceae, the five major groups are shown, including the Ceratopteridoid clade (in bold) which includes the genera Acrostichum and Ceratopteris. Within Ceratopteris, there are about ten species found throughout the world’s tropics (see Figures 2 and 3).
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Phylogenetic and geographic representation of the genus Ceratopteris.
(A) Phylogenetic reconstruction of Ceratopteris, with the sister genus Acrostichum as the outgroup, based on Kinosian et al., 2020a; Adjie et al., 2007; Yu et al., 2021 Zhang et al., 2020. Absent from this phylogeny is the Brazilian species C. froesii, for which no genetic sequence data is available. (B) Distribution map of ten Ceratopteris species: pink, C. richardii; orange, C. shingii; green, C. cornuta; light blue, C. thalictroides; dark blue, C. oblongiloba; purple, C. gaudichaudii; grey, C. pteridoides; black, C. froesii; brown, C. chingii, and red C. chunii. Shaded areas show where a species is common, colored dots show where species occur outside their most common range, or multiple species are found in a small area. Location data from Kinosian et al., 2020a; Lloyd, 1974; Masuyama and Watano, 2010; Zhang et al., 2020; Yu et al., 2021 https://gbif.org/.
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Morphological diversity of four Ceratopteris species.
All photos by SPK unless credited otherwise. (A) Ceratopteris thalictroides mature plant from Townsville, Australia. (B) Detail of a sterile C. thalictroides leaf with buds. (C) Detail of a fertile C. thalictroides leaf. (D) Leaf bases and fiddleheads of C. thalictroides. (E, F) Ceratopteris pteridoides in cultivation at the Dr. Cecilia Koo Botanic Conservation Center in Taiwan. (G) Vegetative buds on C. pteridoides (photo by Christopher Haufler). (H) Ceratopteris gaudichaudii in Cairns, Australia. (I) Ceratopteris richardii in cultivation (photo by David Randall). (J) Ceratopteris richardii gametophytes (photo by Jo Ann Banks).