Monographs Details: Riccia albopunctata Jovet-Ast
Authority: Bischler, Hélène, et al. 2005. Marchantiidae. Fl. Neotrop. Monogr. 97: 1--262. (Published by NYBG Press)
Description:Species Description - Thalli in gregarious patches; lobes 2-3 times forked, 6-15 mm long, 1.3-2.5 mm wide, rounded apically; dorsal side pale green, or bright green with white dots, corresponding to the idioblasts distinct through epidermis; flanks black-violet, nearly completely inflexed when dry; ventral side green, in median portion with narrow strips dotted with pink-violet. Median groove deep apically, vanishing below. Epidermal cells rounded or pyriform, disintegrating except in groove. Ventral scales nearly black and glossy, or brown-violet, rarely only tinged with violet, not extending beyond lobe margins. Cross section of lobes 2-6 times as wide as high, dorsal edge acute laterally with violet, short wings; flanks obliquely ascending or nearly erect; ventral edge flat; dorsal tissue in 3-5 cell layers, each cell with a longitudinal, thin and sometimes pitted strip. Idioblasts scattered, large, 36-40 × 48-76 µm, with white contents. Monoecious. Spores tetrahedral, 100-125 µm diam., orange-brown or light red-brown; wing thin, light yellow, sometimes incomplete, with entire or crenulate margin; distal face with 8-10 areoles across diam., with thin ridges and large, simple or furcate tubercles, to 9 µm high; proximal face with 20-30 tubercles per facet, triradiate scar well marked, consisting of irregular, often interrupted thickenings.

Discussion:Riccia albopunctata is easily distinguished from the other neotropical Riccia species by its white idioblasts, visible through the epidermis as whitish dots. R. campbelliana, the other species with idioblasts occurring in the Neotropics, has different scales and a different spore wall ornamentation.
Distribution:São Paulo Brazil South America| Mato Grosso Brazil South America| Bahia Brazil South America| Santa Catarina Brazil South America| Rio Grande do Sul Brazil South America| Paraná Brazil South America| Misiones Argentina South America| Galápagos Islands Ecuador South America|