Staminode number

Staminode number (female flowers) versus functional stamen number (male flowers) Identical = 0 Different = 1 Lacking = 2... 

Taxon Number of fertile stamen Staminode whorls whorl Staminal appendages Number of sporangia Reference... 

Character optimization shows that in Calamoideae, Ceroxyloideae and Coryphoideae (except Medemia Wurttenb. ex H.Wendl.), the number of staminodes in female flowers is equal to the number of functional stamens in the male flowers, if this is six. This pattern is contrasted in several arecoid genera that have six functional stamens and a different number of staminodes. In one particular clade that includes genera with six stamens and genera with more than... 

Although fruit characters are often of importance (C.D. Pigott, personal comm., 1999), from a practical point of view it was decided to concentrate on flowering specimens to avoid damaging important specimens such as nomenclatural types and because additional characters (e.g. number of flowers per inflorescence, presence or absence of staminodes) could then be used. Also, since fruits often drop off herbarium specimens, the number of flowers in the inflorescence is a more reliable character - essentially the same as the number of fruits in the infructescence (cluster of fruits). A full character list is given by Clark (2000). 

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