Marsupella brasiliensis Bakalin, Maltseva & Schaef .-Verw., 2023

Bakalin, Vadim A., Maltseva, Yulia D., Schaefer-Verwimp, Alfons & Choi, Seung Se, 2023, Marsupella brasiliensis sp. nov. (Gymnomitriaceae, Marchantiophyta) from Brazil - the distribution of sect. Stolonicaulon in Neotropics is now confirmed, PhytoKeys 226, pp. 65-77 : 65

Marsupella brasiliensis Bakalin, Maltseva & Schaef.-Verw. sp. nov.

Description.

Plants wiry, ascending in loose patches, densely intermixed with Cephaloziella sp. and Metasolenostoma sp., perianthous plants strongly clavate, from densely branched and rhizomatous base, sterile branches 120-200 µm wide with leaves, in perichaetium zone to 900 µm wide, rusty to brownish and grading to whitish brown in older parts, with red tint in the leaf apices in the apical part of shoot. Rhizoids virtually absent in leaved shoots, in rhizomatous base sparse and colorless, separated (not united to the fascicles). Stem 70-90 µm in diameter, branching ventral, but new branch always arose near to the ventral base of the leaf and may be regarded as deeply postical-intercalary; cross section nearly orbicular, outer cells with outer wall thin, other slightly thickened (10-)12-14 µm in diameter, inward cell walls become thicker, with large triangular trigones, while cell size become smaller, 8-10 µm in diameter. Leaves obliquely to suberect spreading, slightly narrower to twice wider than stem, 50-180 × 60-190 µm, reniform to widely ovate, smaller constantly entire, sometimes with obtuse apex, larger divided by U-shaped sinus descending to 1/10-1/5 of leaf length, lobes acute. Underleaves absent. Midleaf cells strongly collenchymatous with large and slightly convex trigones, 10-14 µm in diameter to shortly oblong 10-16 × 8-12 µm, cuticle virtually smooth. Paroicous. Perianthous branches distinctly clavate, perigynium high, ca. 1250 × 550 µm, with 3 pairs of leaves whose lower pair composed by strongly ventricose bracts containing antheridia; perianth hidden within bracts, conical, eroding from the mouth, and completely disappearing after sporophyte emergence. Female bracts slightly wider than long, to 500 × 550 µm with gamma-shaped sinus descending to 1/4-1/3 of bract length, lobes triangular, acute, with somewhat diverging apices; bracteoles absent. Androecial bracts in 1(-2) pairs in lower part of perigynium, monandrous. Capsule wall bistratose, outer cells with nodular thickenings present on vertical walls and only sometimes present in horizontal walls; inner layer of rectangular cells with small nodular (not semicircular) thickenings. Spores brownish, 8-10 µm in diameter, faintly papillose, elaters bispiral, (-75)100-130 × 7-8 µm brown, with narrow, but never homogenous ends.

Type.

Brazil, Rio de Janeiro, ca. 22°24'S, 44°41'W, Serra de Itatiaia, Hochgebirgsvegetation auf der Hochfläche bei Abrigo Rebouças, an exponierter, zeitweise sickerfeuchter Felswand [Serra de Itatiaia, high alpine vegetation on the plateau near Abrigo Rebouças, on exposed, intermittently dripping cliff], 2420 m, 15. Oct. 1991, leg. Schäfer-Verwimp & Verwimp 15033 (holotype JE!; isotype VBGI!, PRC, SP (not restudied in the preparation of the present account)).

Illustration in present paper.

Fig. 3 .

Figures

Figure 3. Marsupella brasiliensis Bakalin, Maltseva et Schaef. - Verw. sp. nov. A perianth bearing shoot, fragment B plant habit, fragment, lateral view C plant habit, fragment, ventral view D plant habit, fragment, dorsal view E, F stem cross-section G elaters H-K leaves L capsule, inner layer M capsule, outer layer. Scale bars: 1 mm (a: A); 500 µm (b: B-D, I); 100 µm (c: E-G, L, M); 100 µm (d: H-K). All from 15033 (isotype VBGI).