Two New Species of the Asian Genus Tripterospermum (Gentianaceae)

Abstract—

This paper presents descriptions and illustrations for two new species of Gentianaceae, Tripterospermum maculatum from Sichuan Province (China) and T. tanatorajanense from Sulawesi (Indonesia). Based on literature search, Tripterospermum maculatum is morphologically close to T. pingbianense and T. lanceolatum, and T. tanatorajanense resembles T. luzonense and T. alutaceifolium. To test if the new species differ from their morphologically most similar species, we measured various traits on herbarium specimens and performed a principal component analysis (PCA). This analysis showed that the new species differ from similar species in gross morphology for several diagnostic traits. Tripterospermum maculatum differs from T. pingbianense and T. lanceolatum by having calyx lobes longer than calyx tubes, a whitish-yellow corolla maculated with purple dots, and a gynophore shorter than the ovary. Tripterospermum tanatorajanense is distinct from T. luzonense by having a narrowly winged calyx. It differs from T. alutaceifolium and T. luzonense by having a shorter ovary and a slightly longer gynophore. A key including all species of Tripterospermum is provided.