| Diagnosis |
Thalli consist of unbranched, lanceolate blades (7-12 mm high and 0.8-2.3 mm broad), attached by means of a small discoid holdfast. Growth takes place from a single apical cell, with a typical type-one apical organisation (i.e. all second order row cells produce third order rows). The midrib remains uncorticated throughout. Tetrasporangial sori form discrete, paired ovate sori close to the midrib, 900-1700 μm long and 400-600 μm wide. Tetrasporangial formation involves the lateral pericentral cells but not the transverse ones. Tetrasporangia, 62-80 μm in diameter, are cut off from second- and third order cell rows as well as from cortical cells, resulting in sporangia that lie in more than one plane of the blade. Spermatangial sori form discrete, somewhat oblique patches scattered over the wings. Female plants produce a single cystocarp on the midrib in the distal region of the blades (Ref. 82093). |