Observation 297791: Peltula Nyl.

This collection was from intruded siliceous rock with lots of serpentinite, in a semi-arid grassland setting. The locale is off Highway 46 East in Cholame Valley.

I haven’t sliced these open but they initially appeared to be Peltula, with blue-green algae. They occurred on vertical rock faces on north aspect shaded areas. Thallii were dispersed, up to 1.5cm but usually <1cm, consisting of imbricate lobes with soredia like granules (isidia?) on the margins. of about a dozen thallii collected, one turned out to have apothecia, which are immersed with a reddish disk like Peltula.

I’ll post micro soon, but feel free to guess!


100x in water
100x with KOH
400x K/I stain on asci
400x (cropped) K/I stain, detail of asci
Outer lobes
Lobe underside is pale with soredia?

Proposed Names

-85% (1)
Recognized by sight
57% (1)
Recognized by sight
-46% (2)
Used references: Nash Sonoran Flora. Wetmore 1970 Heppiaceae
Based on chemical features: Epithecium K+R

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

= Observer’s choice
= Current consensus


Add Comment
I forgot all about this wacky thing!
By: Jason Hollinger (jason)
2020-01-25 16:38:26 CST (-0500)

Hmmm, looks like there are quite a number of sequences on Genbank already. One was submitted by the authors Kauff,F., Bachran,A., Schultz,M., Hofstetter,V., Lutzoni,F. and Buedel,B. Maybe there are some people actively working on Peltula now? That would be great.

Thanks for the insight!
By: J-Dar
2017-11-11 16:46:47 CST (-0500)

And no negativity felt, I appreciate the info, always hard to work with determinations for species I’ve no previous experience with. Back to the drawing board! And soon back to the outcrop, there are several others, with varying degrees of serpentine, and all with very well developed crustose communities. Sure makes you think about growth rates, and what actually happens over decades or centuries, or longer, to the species compositions.

Hate to be negative…
By: Jason Hollinger (jason)
2017-11-11 15:37:41 CST (-0500)

But both Peltula obscurans var. obscurans and var. deserticola are abundant in the Mojave portion of our study area in eastern Nevada. And none of our specimens come anywhere close to this. They should be crustose species, not squamulose. I always think they’re Acarospora in the field! Yes, var. hassei is squamulose, but then as you say, the epihymenium is wrong. And don’t forget your spores are way too big for any of the above.

I wonder if you have a new species. Doesn’t look close to any known species. It approaches some forms of Endocarpon pulvinatum… but not with apothecia!! I’ve seen material like this without perithecia or apothecia… now I wonder if they were the same thing as yours. I wasn’t so lucky and didn’t get fertile material. I’ve been holding my nose and lumping it all into Endocarpon pulvinatum(!)

Promising determination made
By: J-Dar
2017-11-11 15:23:25 CST (-0500)

My observation of “soredia” I believe is a mistake, although there are some scurfy granules on the lobe tips. With that, the trail to this ID is pretty straight forward with the squamulose thallus, large number of spores per ascus, ellipsoid spore shape, and K+R epithecium. I have previously identified_Peltula obscurans var. hassei_ in this region (observation 242820 and _observation 258067). But for some reason it looks like I didn’t do micro on these. Looks like I’ll have to dig those up and finish the analysis. I bet I just went on range, because P. obscurans obscurans is not known north of Los Angeles, a couple hundred miles south of here.

Do you have Wetmore 1970?
By: Jason Hollinger (jason)
2017-11-11 13:12:04 CST (-0500)

The Lichen Family Heppiaceae in North America. Annals of the Missouri Botanical Garden 57(2): 158-209.

Photos of lobes added-Still @ Peltula sp.
By: J-Dar
2017-11-11 09:19:37 CST (-0500)

Haven’t committed to this being sorediate, but it seems like it on some lobes. Spores alone don’t fit with anything in the Sonoran Flora, so I’m in a hold pattern until I get some better references.

Micro Update-Photos added
By: J-Dar
2017-11-10 00:06:51 CST (-0500)

Ok, so this is presumably a Peltula, but I can’t match it to anything. Updated description below. I’ll get some close ups of the lobes and soredia.

Thalli are discrete, effigurate, about 0.2-1.2 cm, composed of dull dark brown squamules, with imbricate lobes creating a humped form with marginal lobes spread loosely flat on the rock surface. Lobe tips somewhat scalloped, sorediate, with soredia on the underside of the lobe tip as well as the margin. Apothecia rare, immersed, open reddish disk. Pycnidia common, immersed, showing as black punctiform dots. Lower cortex is pale. Rhizines sparse. Hymenium and hypothecium hyaline, epihymenium yellowish-brown, K+R. Hymenial gel K/I+Blue. Asci broadly clavate, tholus K/I+dark blue. Photobiont a blue-green algae.

Spores many per ascus, small, simple, ellipsoid, hyaline. 11.4×3.7, 10.8×4.5, 9.6×4.1, 10.9×4.1, 8.9×3.8. Average 10.3×4.0µm

Nice outcrop!
By: Jason Hollinger (jason)
2017-11-09 15:12:03 CST (-0500)

Except for possible minor disturbance by quick grassland fires, a community like this could be untold eons old. I bet it’s full of all sorts of interesting parasites, too. I love exploring places like this! (Nevada is chock full of them. Let’s hear it for “useless” land! :)