Evolutionary developmental biology in cycad phenology

Figures & data

Figure 1. A Cycas seemannii megastrobilus (or ‘indeterminate strobilus’ sensu in ref. 28) emerges as a flush of megasporophylls bearing naked ovules, which are almost certainly homologous to the pinnately compound vegetative leaves. The genus Cycas contain some species with pinnately compound megasporophylls, e.g., C. revoluta and C. pectinata,¹¹ while all members of the genus have new flushes of vegetative leaves that emerge from the center of the megastrobilus, as seen in this figure, further indicating homology between sporophylls and vegetative leaves in cycads.

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