Conlarium duplumascospora gen. et. sp. nov. and Jobellisia guangdongensis sp. nov. are described and illustrated from submerged wood collected from Guangdong Province, China. Conlarium duplumascospora is characterized by gregarious, coriaceous and beaked ascomata; cylindrical, unitunicate asci with a bipartite apical ring; biseriate, fusiform, hyaline, 0-5-septate ascospores with or without appendages; and anamorph with muriform conidia. Jobellisia guangdongensis is characterized by globose to subglobose, gregarious and papillate ascomata; three-layered peridium; cylindrical, unitunicate asci with a refractive apical ring; and one-septate, fusiform, greenish brown ascospores. Sequence analyses of partial nuclear large subunit ribosomal DNA (LSU rDNA) were performed to infer the phylogenetic affinities of these new taxa. A key to species of Jobellisia is provided.