Petractis hypoleuca Gyalectaceae
Gyalecta hypoleuca (Petractis hypoleuca)

Growth type crustose. BLS conservation evaluation: VU D2 NR
Chemical results negative. Photobiont Trentepohlia

In Britain and Ireland only recorded from sloping and vertical limestone boulders on the Isle of Portland, Dorset

Thin greyish-white or yellowish-white epilithic thallus, tinged pinkish when fresh. Embedded urceolate apothecia with orangish disc, thick white margin with radiating fissures sometimes absent. Spores 5-9 septate without a perispore, 20-38 x 4.5-7 Ám. Pycnidia absent. Micrographs below

Similar: Petractis nodispora, spores 3-septate, multicellular conidia


Petractis hypoleuca

Petractis hypoleuca

Petractis hypoleuca

Petractis hypoleuca, Gyalecta hypoleuca

Microscope photographs
Petractis hypoleuca, Gyalecta hypoleuca

Petractis hypoleuca, Gyalecta hypoleuca
Gyalecta hypoleuca (Petractis hypoleuca)
On limestone, Portland, Dorset. February and March 2016

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