Data from: Understanding the systematic implications of pollinium morphology of Aeridinae (Orchidaceae)

Molecular phylogenetic studies have suggested major clades in the subtribe
Aeridinae of Orchidaceae. However, systematic
morphological charaters is still lacking. We carried out this
study on the pollinium morphologies of subtribe Aeridinae with
emphases on the aperture types and the pollinium sculpture to
find out their systematic signification in light of a
molecular phylogeny. The results indicate that
most species have cleft type and few with
porate type or none. The shapes of most pollinium are
flat spheroid but not constant at genera levels. The
longth scope of the pollinium is 204-2606 um and the width scope
is 178-1524 um. The long and wide pollinium are easily found in more
primitive groups. The short and narrow pollinium are commonly found in
more evolutionary groups. Shapes and sizes of individual units of
pollinium vary from uniformity to
difference with few
exceptions: isometrical polygons in
Phalaenopsis of Phalaenopsis clade,
Vanda clade and Aerides clade and
irregular shape and different sizes in rest
samples. Individual units of most pollinium are
tetrads and individual pollen grains are easy to
distinguish within the tetrad. The degree of
discriminability of individual pollen grains is
constant at clades level and changes following a tendency except Aerides
rosa: unrecognizable in Chiloschista clade - easily
distinguished in Phalaenopsis clades,
Vanda, Aerides and Gastrocohilus clades - partly distinguished in Trichoglottis and Cleisostoma clade. Exine sculpture characters are consistent in each clades except Cleisostoma clade and Phalaenopsis clade. It has a somewhat clear changing tendency in consist with the molecular phylogeny with few exceptions: from negative reticulum of Phalaenopsis clade - reticulum of Chiloschista clade - levelled psilate surface of Vanda and Aerides clades – bulgy with psilate surface in Gastrocohilus and Trichoglottis clades - two types in Cleisostoma clade. Conclusionarily, these pollinium characters are not systematic but useful characters in determining major systematic groups in subtribe Aeridinae.