Seeking insight on unresolved pollen morphogroups

[Lucia Weinman]

Hello all, 

I am wondering if anyone here may be able to help with identification of three unresolved pollen morphogroups. Pollen samples were taken from scopal loads of bee foragers in deciduous forest understories in Indiana and Michigan. Specimens were collected prior to or at the start of canopy closure, coincident with bloom of spring beauty, Trillium, and other spring ephemerals, red maple, sugar maple, willows, and birches.  In Indiana, this was in April and early May; in Michigan, this was in mid May thru June, depending on latitude of the site.

If you are interested in taking a look, images of the pollens can be found here. 

The first morphogroup (nicknamed "odd.psi" in the images linked above) does not seem to match up with anything in my reference collection. I am guessing that it is a tree pollen just because I am pretty sure I know what the herbaceous pollens look like in this flora. I have reference materials from Juglans, Carya, Fagus, Betula, Carpinus, Amelanchier, Prunus, Cornus, Malus, Ulmus, Acer rubrum/negundo/saccharum/spicatum...Cornus is the closest, but I'm not seeing colporate apertures. There were also basically no Cornus anywhere near my sites as far as I am aware.

As for the other two morphogroups - I haven't felt confident distinguishing between Brassicaceae and Salicaceae, and so I've been lumping them together in my IDs. However, there are two Brassicaceae/Salicaceae moprhogroups that are common in my samples that differ in size and also in the coarseness of the reticulations on the exine. I've been thinking that the smaller morphogroup might be Salix, and the larger Brassicaceae. They are labelled "brass.salix" and "sm.brass.salix" in the folder. I've also included another folder with these labels removed so that folks can look at them blind, if they would prefer.

A note about sample preparation - pollen was stored in 95% ethanol. Fuchsin gel was melted on to a microscope slide. 5 ul of concentrated pollen solution (still in ethanol) was pipetted directly onto the molten gel, and covered with a coverslip.

Thanks in advance, any and all thoughts about any of this are much appreciated!

Best, 

Lucia Weinman

--

PhD candidate | Winfree Lab

Department of Ecology, Evolution and Natural Resources

Rutgers University

luciaraew at gmail dot com

she/her/hers