Two new species of Hypodematium (Hypodematiaceae) from limestone areas in Guangdong, China.

Hypodematium humile F. G. Wang & F. W. Xing and H. villosum F. G. Wang & F. W. Xing, two new species of Hypodematiaceae from Guangdong, southern China, are described and illustrated. Their spore morphology, ecology and conservation status are also presented. Hypodematium villosum differs from H. fordii in having glabrous petiole except on the base, both surfaces of lamina, rachis and costa densely covered with long acicular hairs ca. 1 mm long, and apex of pinnulets acute. Hypodematium humile differs from H. glandulosum in having leaves 8-11 cm long with both surfaces of lamina, rachis and costa sparsely covered with rod-shaped glandular hairs and caducous indusium. A key to the species of Hypodematium known from Guangdong Province is provided. The systematic relationship of Hypodematium with Leucostegia is also discussed. [ABSTRACT FROM AUTHOR]