Plants of the Gila Wilderness

Punctelia graminicola is a grayish foliose lichen. In our area, it seems to have very abundant pseudocyphellae, breaks in the cortex through which fungal hyphae protrude. The pseudocyphellae apparently act as an area of gas exchange, reminiscent of lenticels in trees. The pseudocyphellae appear as white dots on the grayish thallus. P. graminicola grows on boulders and over a large area did not have any apothecia. The cortex is faintly yellow in KOH and the medulla is brilliantly red in sodium hypochlorite. This specimen was collected on a large rock outcrop in mixed conifer forest.
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Punctelia graminicola, growing on large boulder/outcrop, photo Russ Kleinman & Karen Blisard, Pinos Altos Range, McMillan Campground trail, September 27, 2019

Punctelia graminicola, photomicrograph of thallus, photo Russ Kleinman & Karen Blisard, Pinos Altos Range, McMillan Campground trail, September 27, 2019

Punctelia graminicola, photomicrograph of thallus showing green photobiont, photo Russ Kleinman & Karen Blisard, Pinos Altos Range, McMillan Campground trail, September 27, 2019

Punctelia graminicola, photomicrograph of thallus showing pseudocyphellae, photo Russ Kleinman & Karen Blisard, Pinos Altos Range, McMillan Campground trail, September 27, 2019

Punctelia graminicola, photomicrograph of thallus showing white undersurface & rhizines, photo Russ Kleinman & Karen Blisard, Pinos Altos Range, McMillan Campground trail, September 27, 2019

Punctelia graminicola, photomicrograph of cortex faintly yellow in KOH, photo Russ Kleinman & Karen Blisard, Pinos Altos Range, McMillan Campground trail, September 27, 2019

Punctelia graminicola, photomicrograph of medulla bright red in NaOCl, photo Russ Kleinman & Karen Blisard, Pinos Altos Range, McMillan Campground trail, September 27, 2019