2023 Volume 12 Issue 12 Pages 301-306
Isocladiella surcularis （Dixon） B.C.Tan & Mohamed （Musci, Pylaisiadelphaceae） is known to have a distinct morphological dimorphism between plants from Japan and its vicinity and those from Southeast Asia, but this morphological difference is now considered to be continuous, representing a single species with continuous variation and a wide distribution. In this report, we examined whether there are genetic differences among plants showing such geographic dimorphism using rps4 and trnL‒F sequences of chloroplast genomes from 15 samples from Japan and East Asia as well as a single sample from China registered in NCBI. We found that the sequences were completely identical in both rps4 and trnL‒F except for the sample from China showing a single nucleotide difference in rps4. This strongly suggests that I. surcularis should be considered as a single species with a wide geographical distribution, despite the clear geographical variation in morphology as previously suggested.
