Irish lichens

Arctomia fascicularis, Collema fasciculare

Order: Peltigerales       Family: Collemataceae

Species: Arctomia fascicularis (Collema fasciculare)

Growth type foliose.
Photos: Killarney National Park, Co. Kerry, SW Ireland.

Thallus forms small pulpy cushions, very swollen and easily loosened when wet. Lobes often indistinct, short, wrinkled, sometimes lobulate. Apothecia are abundant and often cover the thallus with flat discs, their margins thick and +/- wrinkled. Asci (6-)8 spored, spores 9-17 septate, 50-90 x 4-5 µm, worm-like and spirally twisted in the asci. Micrograph below.

Occurs among moss on trunks of mature trees, usually Ash and Hazel, in western oceanic woodlands. Chemical reactions negative.


Collema fasciculare

Collema fasciculare

Collema fasciculare Micrograph
Collema fasciculare
Arctomia fascicularis (Collema fasciculare) November 2009

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