When: 2011-05-15

Collection location: Colorado National Monument, Mesa Co., Colorado, USA [Click for map]

Who: Chris Parrish (kitparrish)

No specimen available

Locality: 39° 6’2.61"N, 108°44’3.57"W, 1760 m, Canyon Rim Trail

Substrate: sandstone boulders in full sun


Xanthoparmelia of Colorado National Monument, Mesa Co., Colorado

The CNALH checklist for Colorado National Monument includes three species of Xanthoparmelia (data from CNALH):
Xanthoparmelia lineola “without soralia, isidia, or pustulae”
Xanthoparmelia mexicana "moderately to densely isidiate; lobes (0.5-)1.5-4 mm wide "
Xanthoparmelia plittii "moderately to densely isidiate; lobes (0.5-)1-2 mm wide "

Xanthoparmelia mexicana seems to be the best fit for this observation. CNALH remarks that “Xanthoparmelia mexicana is probably the most common Xanthoparmelia in the Sonoran region.”


CNALH page for Xanthoparmelia lineola
CNALH page for Xanthoparmelia mexicana
CNALH page for Xanthoparmelia plittii

Sharnoff Xanthoparmelia lineola gallery
Sharnoff Xanthoparmelia mexicana gallery
Sharnoff Xanthoparmelia plittii gallery


Proposed Names

28% (1)
Recognized by sight
31% (2)
Used references: CNALH photos and descriptions

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

= Observer’s choice
= Current consensus


Add Comment
By: Chris Parrish (kitparrish)
2012-04-22 16:54:43 -05 (-0500)

Interesting. Thanks, Jason. I dropped back to “Could be” as well.

Sorry, have to vote “could be”
By: Jason Hollinger (jason)
2012-04-22 13:38:53 -05 (-0500)

There are just too many species of Xanthoparmelia expected in that area beyond the mere three reported, and even among those, you really need to do the K test to distinguish plittii and mexicana with anything like certainty.

Sorry to be so negative, but Xanthoparmelia is very much in the position Morchella was up until recently: there is strong evidence that it’s a complete taxonomic mess, with dozens of undescribed cryptic species, and just as many poorly defined species which belong synonymized with superficially very different species. Chemistry has been given too much weight, but so has lobe width and degree of adnation, in some cases. I just hate to add to the mess!