Monographs Details: Plagiothecium laetum Schimp.
Authority: Buck, William R. 1987. Bryostephane Steereana: A Collection of Bryological Papers Presented to William Campbell Steere On The Occasion of His 80th Birthday. Mem. New York Bot. Gard. 45: 1-749.
Description:Species Description - Spore morphology: Size: 9-14 µm in diameter, mean 12 µm. Color: yellow, yellowish green or brownish green. Shape: spherical to somewhat ovoid. Sculpture: gemmate, the gemmae irregularly distributed and anastomosing (Figs. 31, 32, 34) or regularly distributed with discrete elements (Figs. 33, 36), 0.1-0.2 µm. in diameter, 0.1-0.2 µm in height, covered with small to large conic papillae (Figs. 35, 36), the spore surface between the gemmae smooth to granulose.