Schusterolejeunea Grolle

Sierra, Adriel M. & Zartman, Charles E., 2023, A taxonomic review of the Amazonian rheophyte Schusterolejeunea Grolle (Lejeuneaceae: Cololejeuneinae), with two new combinations, Cryptogamie, Bryologie 20 (4), pp. 107-122 : 110

Genus Schusterolejeunea Grolle

Journal of Bryology 11: 105-106 ( Grolle 1980).

DESCRIPTION

Plants small to medium size, 1-2.5 mm wide, pale to dark green, creeping to loosely pendent. Stems in cross-section with seven cortical and three medullary thick-walled cells, epidermis slightly enlarged, without hyalodermis. Ventral merophytes are composed of two cells. Leaf lobes obliquely spreading, elliptical, ovate to oblong, 1.5-4 (5) times as long as wide, apices rounded, plane, margins entire, bases of the lobe very narrow, insertion line only 2-3 cells long. Cells pellucid, thin-walled, trigones rare, oil bodies finely granular, 2-4 per cell; ocelli absent. Lobules plane, small to large, variable in shape, when small narrowly lingulate with a narrow base ( S. inundata var. inundata : Fig. 2A, B ), or triangular (finshaped) ( S. inundata var. fontinaloides (Spruce) A.M.Sierra & C.E.Zartman , comb. nov.: Fig. 2C ), when large rectangular to oblong ( S. saxorum (Spruce) A.M.Sierra & C.E.Zartman , stat. nov., comb. nov.: Fig. 2D, E ); hyaline papilla terminal at the apices. Underleaves small (rarely absent in S. saxorum (Spruce) A.M.Sierra & C.E.Zartman , stat. nov., comb. nov.) narrower than the stems, longer than wide, narrowly bifid with erect lanceolate lobes ending in 3-5 uniseriate cells, sinus deeply V-shaped, rarely asymmetrical with one reduced lobe forming a triangular fold consisting of nine cells. Autoicous. Gametoecia numerous along the gametophyte, with either one antheridia or gynoecia branch located below almost every leaf insertion along both sides of the stem ( Thiers 1984). Antheridia on short lateral branches, spikes with 2-6 (8) imbricate pairs of perigonial bracts; bracts ovate bilobed, and emarginate at the apices. Bracteoles arise as underleaves for each bract pair. Gynoecia 2-4 in a monochasial row, each gynoecium with one pycnolejeuneoid or lejeuneoid innovation which is again fertile (except for the outermost one). Perianths obpyriform to obovate, inflated, with five distinct ( S. inundata ) or indistinct low keels ( S. saxorum (Spruce) A.M.Sierra& C.E.Zartman , stat. nov., comb. nov.). Without vegetative reproduction.

Figures

FIG. 2. — Schusterolejeunea Grolle leaf lobule variation: A, B, S. inundata var. inundata (Spruce) Grolle (lingulate); C, S. inundata var. fontinaloides (Spruce) A.M.Sierra & C.E.Zartman, comb. nov. (triangular); D, E, S. saxorum (Spruce) A.M.Sierra & C.E.Zartman,stat.nov., comb.nov.(rectangular to oblong).Scale bar: 150 μm.