PARAVENOUS MESOPHYLL - REVIEW AND SURVEY OF THE SUBTRIBE ERYTHRININAE (PHASEOLEAE, PAPILIONOIDEAE, LEGUMINOSAE)

Paraveinal mesophyll (PVM) is a distinctive anatomical feature of the leaf mesophyll of some plant taxa that may represent a specialized physiological compartment. A comprehensive review of the 42 published references that mention PVM or similar cell layers and a survey of 121 of the 272 species of all nine genera of the Phaseoleae subtribe Erythrininae demonstrate that PVM is nearly exclusively found in Leguminosae. In Leguminosae, PVM is either rare or absent in subfamily Caesalpinioideae, uncommon in Mimosoideae, and extensively distributed among Papilionoideae. In subtribe Erythrininae, PVM is ubiquitous in Erythrina, and occurs in four other genera. Three Erythrininae genera (Apios, Mucuna, and Cochlianthus) lack PVM. Unique chloroplast-poor, enlarged conical cells (pellucid palisade idioblasts) occur in 80 species of Erythrina but not in any other genus of Erythrininae.