@peterbraubach.bsky.social have been following similar lichen trajectories: Polycauliona polycarpa in this thread and some perithecia investigations which I'll post later. I had ignored tiny yellow thalli assuming they were Xanthoria parietina .. but I was wrong. A detailed thread. #lichensGBI 1/3 - ThreadSky

About ThreadSky

sueinscotland.bsky.social • 73 days ago

@peterbraubach.bsky.social have been following similar lichen trajectories: Polycauliona polycarpa in this thread and some perithecia investigations which I'll post later. I had ignored tiny yellow thalli assuming they were Xanthoria parietina .. but I was wrong. A detailed thread. #lichensGBI 1/3

1 / 3

Comments

sueinscotland.bsky.social•73 days ago

Polycauliona is the new name for some Xanthoria species. They will test K+red which can be seen in the photos below of apothecial sections mounted in K. The spores are dumbbell shaped (polarilocular). Some details of the ascus tips also given below. These samples from Scotland, NN7199, vc96 2/3

sueinscotland.bsky.social•73 days ago

Finally, a look at the little orange pycnidia which produce tiny conidia (about 2 x 1 microns) which stream out of a hole at the top when you mount them. 3/3

peterbraubach.bsky.social•73 days ago

Thank you Sue!

Are there other objective features (spore/conidia size e g.) that differentiate X.p. and P. polycarpa? I would look into it, but.. the kids, lunch ... I'll get to it tonight earliest. Maybe you know from the top of your head

sueinscotland.bsky.social•73 days ago

I think looking at the lobe shape and edge is the best way to distinguish if it is a small x.p. thallus. Once it gets bigger, there are no other competitors that come to mind.

aspenecology.com•73 days ago

I agree with Sue's advice. I believe ascospores and conidia of P polycarpa and X parietina are too similar in size and form to provide reliable means for separating these species. Chemistries also indistinguishable by spot-tests. Fortunately, as Sue says, they're morphologically quite distinct.

peterbraubach.bsky.social•73 days ago

Hm. I was just hoping for a second argument.

Posting Rules

Be respectful to others
No spam or self-promotion
Stay on topic
Follow Bluesky's terms of service

Comments

Posting Rules

Reply