Observation 20655: Peltigera polydactylon (Neck.) Hoffm.

When: 2009-03-22

Collection location: Sewanee, Franklin Co., Tennessee, USA [Click for map]

Who: Chris Parrish (kitparrish)

Specimen available

Location: 35°13’21.51"N, 85°57’3.86"W, el. 572 m, Rutledge Point Trail.

Substrate and habitat: Growing on and through a layer of mosses on a near vertical sandstone cliff in a patch of rock given to seepage, in oak-dominated eastern deciduous woodland at the western rim of the Cumberland Plateau.

Identification: Specimens of this lichen were identified by Gary Perlmutter at the UNC Herbarium as Peltigera polydactylon. Gary remarks that the “Peltigera is possibly two taxa, one with small lobes and another with large ones. I’ve split the sample into 031 (small lobed) and 031a (large lobed). Both are P. polydactylon s. lat. While Brodo et al. (2001) keys the large lobed to possibly P. neopolydactyla, Harris & Ladd (2005) are more cautious: ‘We do not pretend to understand the P. polydactylon complex in eastern North America.’ I’ve grown to err on the side of caution, and this being more recent than Brodo et al., am following Harris and Ladd.”

Interesting to compare the relatively sparse, dark, bushy or cable-like rhizines in these photos with the dense, white, smartly regimented, sabre-tooth rhizines in Observation 13159.

Sharnoff’s Peltigera polydactylon gallery
Stridvall’s Peltigera gallery
CNALH images and locality map, and a larger, interactive locality map.

Voucher specimen: Tennessee, Franklin County, Sewanee, Rutledge Point Trail, 22 Mar 2009, Chris Parrish 0031, det. Gary Perlmutter (NCU)

Common name: many-fruited pelt (The apothecia in this species are striking, but I haven’t found any yet! See the photos in Observation 13159 and in Brodo, p.518.)

Species Lists


Rutledge Point Trail, 2009_03_22
Rutledge Point Trail, 2009_03_22
Rutledge Point Trail, 2009_03_22
Rutledge Point Trail, 2009_03_22
Rutledge Point Trail, 2009_03_22
rhizines, 12.5x
rhizines, 16x
rhizines, 16x
rhizines, 16x
thallus, 7.1x
thallus, 7.1x
thallus, 7.1x
thallus, 7.1x
thallus, 7.1x
thallus, 10x
crisped thallus margins, 10x
undersurface, 10x
undersurface, 16x

Proposed Names

56% (1)
Eye3 Eyes3
Recognized by sight: Specimens of this lichen were identified by Gary Perlmutter at the UNC Herbarium as Peltigera polydactylon.
Used references: Brodo, Sharnoff, Sharnoff, 2001, p.517-518; Harris and Ladd, 2005, p.173-174

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

Eye3 = Observer’s choice
Eyes3 = Current consensus


Add Comment
By: Jason Hollinger (jason)
2009-04-28 14:41:53 CDT (-0400)

Yes, I’m still very unsure of the ID of observation 13159: depending on how you classify the veins (which are not visible in my photos) it may also key out to P. degenii; and depending on how broad and wavy the lobes are, it could key out to P. neopolydactylon. Actually, I think I would go with that knowing what I know now, but that is still too little to be sure, and Gary’s comments about the taxonomic state of thes polydactyon group convince me not to try!

As for rhizines. In this group they should “mostly taper to a point” (Trevor Goward’s key). I see at least one of yours tapering to a point (e.g. image 42161). I believe it is important to look at the rhizines near the edge that are not yet actually attached to the substrate. (All attached rhizines will eventually splay out upon touching the substrate.) I don’t actually see any “pristine” rhizines in your photos, interestingly. Not sure what that means. So I would be hesitant to classify your rhizines as “bushy” based on the photos. As for color… Well, you can only see the very youngest rhizines on my observation; generally older rhizines turn darker in my limited experience, even in species which supposedly have white undersides.

Good point…
By: Jason Hollinger (jason)
2009-04-28 04:06:14 CDT (-0400)

It is interesting to compare to my observation 13159, isn’t it?… But just between you and me, I haven’t a clue when it comes to Peltigera, for all I know it’s a completely different species!

Created: 2009-04-27 23:29:38 CDT (-0400)
Last modified: 2009-04-27 23:29:38 CDT (-0400)
Viewed: 401 times, last viewed: 2018-08-01 22:16:04 CDT (-0400)
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