Observation 72237: Physconia perisidiosa (Erichsen) Moberg

When: 2011-07-20

Collection location: Black Hills, South Dakota, USA [Click for map]

Who: Jason Hollinger (jason)

No specimen available

Wetmore has this to say about his Physconia “grisea”:

This variable species is represented in the Black Hills by several forms or variations. Some collections with soredia on the under side of the tips of the lobes correspond to f. farrea (Ach.) Lynge [P. perisidiosa], some with yellow soredia as in f. enteroxanthella (Harm.) Erichs. [P. enteroxantha and possibly P. leucoleiptes] and there are still others with a K+ yellow upper cortex [Physcia biziana and/or Physcia dimidiata maybe?] which Thomson says is a rare variant of this species. I consider them hardly worthy of formal taxonomic recognition[!].

As it happens, Esslinger and others did consider these “forms” worthy of taxonomic recognition at species level. Thus Wetmore’s Physconia “grisea” probably refers to the following, among possibly others:

Physconia detersa – K- KC-, marginal soredia
Physconia perisidiosa – K- KC-, soredia under tips
Physconia enteroxantha – K- KC+y medulla, marginal soredia
Physconia leucoleiptes – KC+y soralia, fine marginal soredia
[Physcia biziana? – K+y cortex, no soredia, I’ve seen this here on aspen]
[Physcia dimidiata? – K+y cortex, marginal soredia, I haven’t seen this]

Species Lists

Proposed Names

-87% (1)
Recognized by sight
87% (1)
Recognized by sight: According to Esslinger, P. grisea doesn’t occur in North America. Going by Wetmore’s description (soredia on tips), this can only refer to P. perisidiosa, which I have personally observed at a number of locations in the Black Hills.

Please login to propose your own names and vote on existing names.

= Observer’s choice
= Current consensus


Add Comment
Paul, these are all “fake” observations
By: Jason Hollinger (jason)
2011-08-19 22:58:34 PDT (-0700)

I just wanted to upload the list of species covered in Wetmore’s old flora of the Black Hills. MO will automatically take care of most synonymy, so it was very useful to me when going through my own collections which haven’t made it onto MO yet. I could probably fake a better date for these observations, and in fact, I could literally place each observation very precisely in both time and space, since Wetmore listed all the specimens he saw from literally hundreds of collection locations. He was very thorough. But that seemed a bit overkill!

By: Paul Derbyshire (Twizzler)
2011-08-19 22:45:00 PDT (-0700)

Created: 2011-07-20 10:01:38 PDT (-0700)
Last modified: 2011-07-21 09:05:13 PDT (-0700)
Viewed: 68 times, last viewed: 2019-02-14 07:43:59 PST (-0800)
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