Plant Species of the Bright Angel Trail:
Cryptantha pterocarya

See Plant Guide to Bright Angel Trail for an introduction to this page, especially the Introduction To These Species Pages.


Identification status: 100%. This is a very distinctive species due to the winged nutlets with lobes on the upper part of the wings. It is one of the few cryptanthas that are easy to recognize in the field by the fat calyx (due to the nutlet wings) that dwarfs the small flowers.

The plant I examined has 2-4 nutlets per flower, with a mostly-unwinged nutlet in the flowers with 3 or 4 nutlets. This would make it var. pterocarya if one accepts the varieties; see C. pterocarya (Torrey) Greene.

From a SEINet search on 10 May 2008, there are three vouchers of this species from the Bright Angel Trail. The nearest are at: near the Colorado River at the bottom; and on River Trail, just west of suspension bridge. Another voucher is just given as being at 36.06917, -112.13222, which may or may not be a precise location. Note that there may be additional vouchers at other herbaria not available through SEINet.

First occurrence on Bright Angel Trail: mile 3.75, elevation 4200 feet (1280 m).

Number of plants along Trail: at least two plants were found in at least one different locations in May 2008. The survey stopped at the location of these plants, so it is quite likely there are more plants farther along the trail.


I ran out of time to take pictures in the field. As I recall, the plants were about a foot high, slender and erect. The following pictures are taken through a microscope. The calyx in the picture is 4.0 mm long; the flower is ~1.2 mm wide across the top. The nutlets are 2.0 mm long.

From 6 May 2008, mile 3.75:

The nutlets on the left show the opposite side relative to the nutlets on the right. The nutlet at bottom right is the odd nutlet, with poorly developed wings, generally found in each flower along with 2-3 of the normal nutlets.


See Resources for Grand Canyon Flora for further information on most of these references. Entries in the second column are either the name used in that source or a page reference. The name is linked to online pages when available. If a given reference does not contain this taxon, the entry is either left blank or contains a hyphen.

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Copyright © 2008 by Tom Chester.
Permission is freely granted to reproduce any or all of this page as long as credit is given to me at this source:
Comments and feedback: Tom Chester
Last Update: 10 May 2008