TY - JOUR T1 - A search for phylogenetically informative pollen characters in the subtribe Salviinae (Mentheae : Lamiaceae) JF - International Journal of Plant Sciences Y1 - 2008 DO - 10.1086/526463 A1 - Hye-Kyoung Moon A1 - Stefan Vinckier A1 - Jay B Walker A1 - Erik Smets A1 - Suzy Huysmans SP - 455–471 KW - Distyly KW - Grains KW - Labiatae KW - Morphology KW - Orbicules KW - Palynology KW - Perovskia KW - Phylogeny KW - Pollen Dimorphism KW - Salviinae KW - Systematics AB - The pollen morphology and ultrastructure of the subtribe Salviinae were investigated with light, scanning electron, and transmission electron microscopy. In addition, cladistic analyses of the obtained morphological data, supplemented with rbcL data from GenBank, were conducted in order to assess the phylogenetic signal of palynological characters. Salviinae pollen is small to large, oblate to prolate in shape, with a circular to slightly elliptic amb, and mostly hexacolpate. Perovskia abrotanoides appears to be distylous and shows a significant pollen dimorphism between pin and thrum flowers. The sexine ornamentation of the genera Lepechinia and Chaunostoma is perforate, while the ornamentation of other genera is bireticulate. Perovskia expresses a unique type of sexine ornamentation. The sexine ornamentation variation in Salvia has systematic importance but only partly corresponds with current phylogenetic hypotheses. Unbranched columellae and a continuous, granular endexine are hypothesized to be a symplesiomorphic condition in the tribe Mentheae. Our combined phylogenetic analyses show that the addition of palynological characters contributes to improved resolution and also increases bootstrap support values in comparison with molecular phylogenetic analyses. VL - 169 UR - http://www.journals.uchicago.edu/doi/abs/10.1086/526463 ER -