Palynotaxonomy of the species of the Schultesia mart. Gentianaceae Juss.

Abstract

This work is part of a more comprehensive study of taxonomic review of Schultesia Mart. Pollen grains of 17 species have been analyzed: S. angustifolia Griseb., S. aptera Cham., S. australis Griseb., S. bahiensis E.F.Guim., S. benthaniana Klotzsch., S. brachyptera Cham & Schltdl., S. crenuliflora Mart., S. doniana Progel, S. gracilis Mart., S. guianensis (Aubl.) Malme var. guianensis, S. guianensis var. latifolia (Mart ex Progel) E.F.Guim., S. heterophylla Miq., S. lisianthoides (Griseb) Hemsl., S. minensis E.F.Guim., S. pachyphylla Griseb., S. pohliana Progel and S. sucreana E.F.Guim. Polliniferous material was obtained from herbaria, it was acetolized, measured, described and illustrated by light microscopy and scanning light electronic microscopy. The results reveal that the taxa of Schultesia, which have been studied have pollen grains medium or large size in tetrahedral tetrads, medium or large, calymnate, with an sub- triangular outline, 3-hemicolporate or 3-anaporate (only in S. pachyphylla), heterobrochate sexine. The pollen grains, which form the tetrads, are medium or large, triangular when the entire group is observed by side view. The apertures (colporate) are better observed when the tetrad is in side view, each pollen grain has 3-hemicolpi, which in most species are surrounded, by a broad concave psilate margo, small in S. heterophylla or without it in S. lisianthoides and S. sucreana. When there are pores (S. pachyphylla), they are located in the distal pole (anaporate). It can be concluded that pollen grains of Schultesiaspecies presented some similarity among them indicating that the genus is palynologically homogeneous. Only in S. pachyphylla the tetrads were different because there are pores in the distal pole and the reticulum has another type of organization. The other species were grouped on the presence or absence of an apertural margo.