Ephedra: Distribution, Features and Reproduction - Biology …
WEBFemale Strobilus (Ovulate Strobilus) or Female Cone: They usually arise in pairs at each node in the axil of scale leaves. A female strobilus appears to be an elliptical structure with a pointed apex (Fig. 11 A, B). It retains the same compound structure as the male strobilus.
The Earliest Fleshy Cone of Ephedra from the Early Cretaceous …
WEBJan 14, 2013 · Bracts of female cones of Ephedra are modified foliar organs in nature. In living Ephedra, cone bracts have three states according to their mature morphology, e.g., fleshy bracts, dry and coriaceous bracts, and dry …
A Review on Worldwide Ephedra History and Story: From Fossils …
WEBApr 30, 2020 · Ephedra macrofossils, especially female cones, provide a historical perspective for the early evolution, taxonomy, and biogeography of this genus.
female reproductive unit of Ephedra (Gnetales): comparative …
WEBAug 25, 2010 · The female cone of Ephedra comprises cone bracts in decussate arrangement or in whorls of three. In the axil of the most distal pair or whorl of bracts there are one to three ovule(s), each surrounded by a seed envelope ( Figs 1 , 2 ).
Full article: Fleshy Structures Associated with Ovule Protection …
WEBJul 6, 2021 · Ephedra species are dioecious, and there is only one extant species that bear sterile ovules on male cones: E. foeminea (Jörgensen and Rydin, Citation 2015). Male and female cones have decussate pairs of bracts, which bear reproductive complexes (Endress, Citation 1996; Rydin et al., Citation 2010). In particular, female cones appear in form ...
Ontogeny of triovulate cones of Ephedra intermedia and origin …
WEBMar 1, 2004 · Female cones of Ephedra have two basic patterns including bimerous female cones and trimerous female cones. Cladistic analyses have suggested that bimerous phyllotaxy (manifested in leaves and bracts) is the synapomorphic state of gnetalean plants ( …
The female reproductive unit of Ephedra (Gnetales): comparative ...
WEBWe document morphological, anatomical and histological variation patterns in the female reproductive unit and test the hypothesis that some Early Cretaceous fossils, which share synapomorphies with Ephedra, are members of the extant clade. Results indicate that some morphological features are evolutionarily informative although intraspecific ...
The Earliest Fleshy Cone of Ephedra from the Early Cretaceous …
WEBOct 1, 2013 · Early Ephedra might have transformed bracts of female cones into fleshiness and vivid color to assist seed dispersal [13–15], resulting in a wide intercontinental distribution of the genus.
Asymmetrical development of biovulate cones resulting in …
WEBFeb 12, 2007 · Female cone morphology in Ephedra, including the number of initiated ovules and mature seeds per cone, provides important taxonomic characters used in sectional or species delimitation within Ephedra. Recent molecular phylogenies have indicated, however, that seed number per cone has changed repeatedly during the evolution of the genus.
The female reproductive unit of Ephedra (Gnetales): Comparative ...
WEBAug 1, 2010 · ... The Ephedra dispersal unit is the seed cone, found in female individuals of this dioecious gymnosperm, consisting of three pairs of decussate bracts and two ovules (except for a few...