Parmotrema specimen 2

Specimen.

Stuttgart State Museum of Natural History, Germany (SMNS), SMNS -DO-4929-M.

Age and stratigraphic level.

15‒20 Ma, Langhian – Burdigalian (early to middle Miocene), La Toca Formation, Dominican Republic.

Description.

Three lichen fragments situated very closely together, most probably originating from the same thallus (Fig. 7 E); whole inclusion approximately 5.0 × 2.4 mm in diameter. Thallus foliose, lobate. Lobes flat, broad to linear, 0.4–1.0 mm wide, lobe apices truncate to rounded (Fig. 7 E). Upper surface smooth and brown, with dark margins (Fig. 7 D). Marginal cilia dark, branched, and long (up to 0.8 mm) (Fig. 7 E). Medulla not visible. Lower cortex dark. Rhizines dark. Pycnidia abundant on the upper surface (Fig. 7 D). Apothecia, isidia, or soredia not present.

Discussion.

The general habit, very long, branched marginal cilia, and dark lower surface identify the specimen as Parmotrema . Of the infrageneric groups, the dark lower surface without rhizines reaching the margins could represent, for example, the Parmotrema s. str. group.