Monographs Details: Riccia bahiensis Steph.
Bischler, Hélène, et al. 2005. Marchantiidae. Fl. Neotrop. Monogr. 97: 1--262. (Published by NYBG Press
Description:Species Description - Thalli in gregarious patches; lobes bifid, linear, 4-6 mm long, 1-1.5 mm wide, rounded and slightly emarginate apically; dorsal side light brown. Median groove wide (fide Stephani, 1898). Pores 28-30 µm diam., bounded by 5 cells. Ventral scales absent. Cross section of lobes 0.7-0.8 mm high, usually twice as wide as high; dorsal edge rounded laterally; flanks ascending; ventral side slightly convex; air chambers in 2-3 layers; ventral tissue in 5 layers. Monoecious (fide Stephani, 1898). Archegonia deeply embedded in ventral tissue, separated from ventral epidermis by a single layer of cells. Sporangia ventrally bulging. Spores tetrahedral, 70-84 µm diam., red-brown with darker ornamentation; wing 4.8-5.5 µm wide, complete or incomplete, granulose; distal face with 3-5 complete or incomplete areoles, with thick and ± sinuose ridges, in some with a central ornamentation of 1-3 thickenings; proximal face with irregular areoles, more numerous and smaller than those of distal face, with thinner ridges, triradiate scar well marked.
Discussion:Riccia bahiensis has often been considered a synonym of R. cavernosa (e.g., Schuster, 1992b). However, in R. bahiensis the flanks of the lobes are nearly erect and the spores are smaller, with thicker ridges delimiting complete areoles on distal face and with more numerous areoles on proximal face.
Distribution:Brazil South America
| Bahia Brazil South America