Taxonomic notes and range extension of several complex thalloid liverworts

Riccia billardierei Mont. & Nees and R. rhenana Lorb. ex Mull.Frib. were found in Southern China. Phylogenetic analyses of the genus Riccia based on the sequences of rbcL, rps4, and trnL-F reveal that two Chinese samples of R. billardierei and six samples from Australia and Thailand form a well-supported clade, which is sister to R. gangetica. Riccia rhenana is molecular-phylogenetically investigated for the first time and it is sister to R. fluitans L. Sphaerocarpos siguniangensis R.L.Zhu & You L.Xiang was discovered for the first time outside the type locality. The Chinese Exormotheca bischlerae Furuki & Higuchi, previously known only from Sichuan, was newly found in Yunnan and Xizang. In addition, Aitchisoniella himalayensis Kashyap and Peltolepis quadrata (Saut.) Mull. Frib. rare in China were found for the first time in Yunnan and the Qinghai-Tibet Plateau, respectively. Illustrations of Aitchisoniella himalayensis, Exormotheca bischlerae, Peltolepis quadrata, Riccia billardierei, R. rhenana, and Sphaerocarpos siguniangensis are provided.