Peltigera venosa cyanomorph established before phycomorph?

My impression is that the P. venosa photomorph with cyanobacteria (Nostoc) was established and then lobes of the green algal (Coccomyxa) photomorph grew

Townsend from north
image 5.6cm across

another term for photomorph - "photosymbiodeme (noun, pl. photosymbiodemes; synonym: morphotype pair) – a lichen fungus forming morphologically and anatomically identical (isomorphic) or different (heteromorphic) thalli with different photobionts; e. g., Peltigera spp., Sticta spp., Nephroma spp. (isomorphic), Dendriscocaulon-Lobaria (heteromorphic)." - glossary.lias.net/wiki/Photosymbiodeme?version=2

regarding all these -sym- containing words - "In 1877, Bennett [disputed?] used “symbiosis” to describe the mutualistic relationship in lichens. Then, the German botanist and father of plant pathology, Heinrich Anton de Bary, used this term in 1879 to describe all cases where different organisms lived together in a mutually beneficial relationship." - www.wyzant.com/resources/lessons/english/etymology/words-...

"De Bary also studied the formation of lichens which are the result of an association between a fungus and an alga. He traced the stages through which they grew and reproduced and the adaptations that enabled them to survive drought and winter. He coined the word "symbiosis" in 1879 in his monograph "Die Erscheinung der Symbiose" (Strasbourg, 1879) as "the living together of unlike organisms". He carefully studied the morphology of molds, yeasts, and fungi and basically established mycology as an independent science." - en.wikipedia.org/wiki/Heinrich_Anton_de_Bary

"In foliose lichens, sometimes two phototypes are formed by probably the same mycobiont which lives in symbiosis with either green or cyanobacterial photobionts. Moreover, the same mycobiont can also form two different morphotypes, which are present as cyanobacterial fruticose thalli growing on green lobate thalli. This occurs particularly in the genera Peltigera, Lobaria, Nephroma, Sticta and Pseudocyphellaria. The “one fungus-two photomorphs“ hypothesis (Goffinet and Bayer 1997) implies that one lichen fungus can live in a symbiotic relationship with either (prokaryotic) cyanobacteria and/or (eukaryotic) green algae. The often-used term “photosymbiodeme“, derived from the former phycosymbiodeme (Renner and Galloway 1982), includes lichens forming dimorphic thalli, thalli with different green algal or cyanobacterial photobionts (“cyanobionts“) and cephalodiate thalli. The origin of photosymbiodemes is far from understood, as is their presence or absence in natural ecosystems. Perhaps symbiotic ascomycetous fungi evolved a high phenotypic plasticity that allowed them to respond to changing conditionsin their environment. Field studies of Sticta filixrevealed that light intensity determines whether the green phototype or the cyanotype differentiates (Poelt 1986). Between the green and cyanobacterial morphotypes, mixed phototypes (photosymbiodemes) are found." - abstract of link.springer.com/chapter/10.1007/978-3-642-56359-1_3

interesting photomorphs - www.anbg.gov.au/lichen/form-structure-sticta.html

an interesting paper - www.ncbi.nlm.nih.gov/pmc/articles/PMC3400443/

my lichen photos by genus - www.flickr.com/photos/29750062@N06/collections/7215762439...

my photos arranged by subject, e.g. mountains - www.flickr.com/photos/29750062@N06/collections

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Taken on: September 2, 2020

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Peltigera venosa

photomorph

photosymbiodeme

Sets appears in: • of interest • Peltigera more » • Psoroma • all lichens 6th set « less

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