Rudolgaea, AND

Potemkin, A. D. & Vilnet, A. A., 2021, Reappraisal of Gymnocolea and description of a new genus Rudolgaea (Anastrophyllaceae, Marchantiophyta), Arctoa 30 (2), pp. 138-148 : 145-146

KEY TO SPECIES OF RUDOLGAEA AND GYMNOCOLEA

1. Pigmented plants blackish brown, sometimes with traces of purple, not lustrous when wet; rhizoids never originate from leaf bases; cortical cells of larger shoots subequal to inner stem cells and orientated largely radially; perianths common, frequently caducous; on acid soil, rocks, in oligotrophic mires, and wet habitats .................................... Gymnocolea inflata s.l.

— Pigmented plants yellow and golden brown, when wet lustrous, or scorched brown and not lustrous; some rhizoids or their fascicles, when present, originate from ventral leaf bases; cortical cells of larger shoots mostly ± smaller than inner stem cells and often orientated tangentially in larger stem cross-sections; perianth rare, not caducous; in acid to subneutral wet habitats .............................................. 2

2. Pigmented plants yellow and golden brown, when wet lustrous; rhizoids absent, few or ± abundant in some shoot sectors, single rhizoids sometimes originate from leaf bases; leaf and stem surfaces remarkably striolate papillose; leaf cells with 1–6(–8) oil bodies; cortical cells 12–20(–25) µm wide; stem (7–)9–11 cells high; in subneutral wet habitats with dense vegetation, in moderately to extremely rich fen vegetation, in carpets to lawns, where the groundwater level in summer lies well below the surface, never in intermediate fens and on hummocks in Scandinavia; in wet hollows of cotton-grass-sedge bog between flat mounds in the Gydansky Peninsula ........................ ................................................. Rudolgaea borealis

— Pigmented plants scorched brown, never lustrous; rhizoids very few or sparse, in more or less distinct fascicles from the ventral leaf base and adjacent part of the stem (leaves detach with rhizoids); leaf and stem surface faintly striolate papillose or smooth; leaf cells with (2–)5–12(–16) oil bodies; cortical cells broader, (20–)23–28(–30) µm wide or when subisodiametric (28–)30–34(–38) µm wide; stem (5–)6–8(–11) cells high; in acid wet habitats, including troughs of polygonal tundras, in Sphagnum tussock bog and bogs with flowing water, in herb-willow, grass-cotton grass and sedge-lichen-moss tundras, often among Drepanocladus s.l. and Sphagnum , with Scapania paludicola var. rotundiloba , Ptilidium ciliare , Pseudolepicolea fryei , Barbilophozia kunzeana , B. binsteadii , Gymnocolea inflata , Odontoschisma elongatum , Blepharostoma , etc. (Potemkin, 1993) ........ Rudolgaea fascinifera