Comparisons of corolla morphology were made between plants of Conandron ramondioides (Gesneriaceae) from 23 localities in Japan and Taiwan. Lobe-length to tube-length ratios were found to correlate with geographical distribution and support the recognition of two previously described varieties: var. ramondioides in mainland Japan (lobe length less than twice tube length) and var. taiwanensis from Iriomote Island (Japan) and Taiwan (lobe length more than three times tube length). Mitotic chromosomes were also observed but no differences were seen between accessions, all of which had 2n=32.