Leonardosia Langei Sommer (charophyta, Porocharaceae) From Corumbataí Formation (guadalupian), Piracicaba, Sp, Brazil: First Record Of An Antheridium And Of Corticated Thalli

Fossilized portions of a charophyte found in close association with disperse gyrogonites identi- fied as Leonardosia langei Sommer are described. One sample has an antheridium apparently connected to a thallus clearly corticated. Considering the close association and the lack of other carophyte species than L. langei the thalli are thought to belong to this species. The male structure is very rare and is recorded for the first time in L. langei and in the Porocharaceae. The samples consist of compressions/impressions from the Corumbatai Formation (Guadalupian of the Parana Basin), found in the municipality of Piracicaba, in the Brazilian state of Sao Paulo. The presence of such algae provides evidence of some of the palaeoenvi- ronmental conditions prevailing during the deposition of the Corumbatai Formation: a low energy envi- ronment, probably along the margin of a shallow inland sea not directly connected to the ocean.