Lycopodiopsis derbyi Renault from the Corumbataí Formation in the state of São Paulo (Guadalupian of Paraná Basin, Southern Brazil): new data from compressed silicified stems - Faria, Rafael Souza de; Ricardi-Branco, Frésia; Giannini, Paulo César Fonseca; Sawakuchi, André Oliveira; Del-Bem, Luiz-Eduardo (Review of Palaeobotany and Palynology, 2009)