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.