In an opposite pattern, if successive leaf pairs are 90 degrees apart, this habit is called decussate.It is common in members of the family Crassulaceae Decussate phyllotaxis also occurs in the Aizoaceae.In genera of the Aizoaceae, such as Lithops and Conophytum, many species have just two fully developed leaves at a time, the older pair folding back and dying off to make room for the …

