Tables and diagrams
Origins of spines and prickles
Areole and spine development
The left panel shows the positions of radial and central spines. The central panel connects the areole with stem tissues, and the right panel shows the elongated, hard cells of a mature spine. An areole is a short shoot that also produces hairs and other structures. [Mauseth 2006] [Silva et al. 2020]
The information about absence of xylem and phloem concerns ordinary spines. Specialised secretory glochids described in two species have a vascularised base and are shown on a separate plate.
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