The families of gymnosperms
Unless indicated otherwise, the following attributes are implicit throughout the descriptions, except where the characters concerned are inapplicable.
Vegetative. Leptocaul. Plants of conventional form. Not Casuarina-like switch plants. Without coralloid, cyanobacteria-containing root masses. With normal leaves. Mature leaves simple; not dimorphic.
Reproductive organization. The reproductive organization not flower-like.
Fertilization not involving motile spermatozoids.
Seeds and seedlings. Seeds with no fleshy investment.
Wood anatomy. Secondary xylem lacking vessels. Torus extensions absent.
To view the illustrations with detailed captions, go to the interactive key. This also offers full and partial descriptions, diagnostic descriptions, differences and similarities between taxa, lists of taxa exhibiting or lacking specified attributes, and distributions of character states within any set of taxa.
Cite this publication as: ‘Watson, L., and Dallwitz, M.J. 2008 onwards. The families of gymnosperms. Version: 9th April 2015. delta-intkey.com’.