Term:

Appendage-free ligule
Definition:

The part of a ligule between the staminal ring and the androecial hood that is free of stamens, staminodes, and vestigial stamens (collectively called appendages), or at least the appendages are very sparse compared to their density in the staminal ring or on the hood.
Notes:

There are very few species of neotropical Lecythidaceae that do not have an appendate-free ligule, the most spectacular example is Couroupita nicaraguarensis with continuous appendages densely covering the ligule from the staminal ring to the end of the ligule. Species of Cariniana also have stamens all over the inside of the staminal tube as well as on the staminal tube extension. However, we consider the prolongation of the staminal tube as a staminal tube extension and reserve ligule for an extension from the staminal ring.
Related Terms:

Ligule