Monographs Details: Riccia taeniaeformis Jovet-Ast
Bischler, Hélène, et al. 2005. Marchantiidae. Fl. Neotrop. Monogr. 97: 1--262. (Published by NYBG Press
Description:Species Description - Thalli in crowded mats; lobes bifurcate, 10 mm long, 1-2.2 mm wide, thin, rounded or slightly emarginate apically; dorsal side pale green, sometimes with violet strip along margins. Median groove distinct apically only. Epidermal cells thin-walled, persistent, rectangular. Ventral scales colorless, small, with cells 48-75 × 36-48 µm, or absent. Cross section of lobes 0.7 mm high apically, 0.4-0.5 mm below; dorsal edge with thin wings laterally; flanks obliquely ascending, ending apically in the thin wings, with acute apical cell; ventral edge convex; dorsal tissue in 4(-5) layers. Dioecious? Sporangia bulging ventrally. Spores tetrahedral, (84-) 110-125 µm diam., red-brown with dark brown ornamentation; wing crenulate, irregular, yellow, 4-7 µm wide; distal face with 5-10 areoles across diam., with thin ridges and conspicuous tubercles; proximal face with conspicuous tubercles or with tubercles mixed with short, sinuose or straight ridges, triradiate scar conspicuous.
Discussion:Riccia taeniaeformis is apparently related to R. albopunctata, with which is shares the same ornamentation on the proximal spore face. However, idioblasts are lacking in R. taeniaeformis, and the flanks of the lobes are not tinged with violet. Additionally, the scales are very small or absent in R. taeniaeformis.
Rio Grande do Sul Brazil South America