have several staminodes (Endress, 1980), which added to the number of stamens, at least in some 
flowers, point to the presence of a fifth whorl lost during evolution. Based on this evidence 
supernumerary whorls in the ingroup are considered plesiomorphic. 0, supernumerary whorls of 
stamens present; 1, supernumerary whorls of stamens absent. 
15. Condition of fourth whorl stamens. The transformations in the stamens of the fourth 
whorl have usually been considered important for recognizing groups within the Lauraceae. One 
of these modifications is their change into staminodes. The degree of reduction in their structure 
up to their final elimination form another set of useful characters. Once the stamens are sterile 
they don't turn back to the fertile condition. Therefore, this change is taken as irreversible. But 
the steps between the extremes may not take place necessarily in an ordered way, as the several 
combinations of fertile stamens with different transformation states of the fourth whorl suggest 
within the genera of Lauraceae. In other words, the change from fertile to sterile is considered 
equally possible as the direct change from fertile to absent. This character is coded following the 
previous comments (see figure 20 for explanation). 0, fertile; 1, staminode differentiated; 2, staminode 
undifferentated; 3, absent. 
16. Condition of inner sporangia, fourth whorl stamen. Orientation of the sporangia is 
particularly hard to decipher in evolutionary terms. Introrse and extrorse condition are found 
among different taxa in the Magnoliideae. The same situation is present within the Monimiaceae. 
Hortonia has extrorse anthers, but this condition is rather uncommon in the Lauraceae. The 
decision of considering extrorse dehiscence plesiomorphic was complemented with a second 
option where introrse dehiscence is plesiomorphic. Changes from latrorse to either extrorse or 
introrse states, or vice versa, are regarded as equally possible. Even the direct change from 
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