Didymocarpus phuquocensis, a new species of Gesneriaceae from Phu Quoc Island, South-western Vietnam

Didymocarpus phuquocensis, a new species of Gesneriaceae from Phu Quoc Island, South-western Vietnam

Thi-Lien Tran, Ngoc-Sam Ly, Minh-Ngoc Tran, Xuan-Truong Nguyen, Ngoc-Giang Cao, Hong-Dung Pham

Abstract

A new species of Gesneriaceae, Didymocarpus phuquocensis, is described and illustrated from Phu Quoc National Park, Kien Giang Province, South-western Vietnam. It is most similar to D. pulcher, D. hookeri and D. punduanus in having 3-verticillate petiolate leaves, morphologically similar calyx, corolla, stamens, pistil and fruit, but differs from all in the glandular-pubescent stems, petioles and leaf blades, 1(–2)-flowered cymes, longer corolla and fruit and longer and densely glandular-puberulent ovary. Data on distribution, ecology, phenology and provisional conservation assessment of the new species are given along with an illustration and a colour plate.

Keywords

Didymocarpus, Kien Giang, new species, taxonomy, Vietnam

Figure 1. 

Didymocarpus phuquocensis A flowering plants in natural habit B flowering plants showing 3-verticillate leaves (red arrow) C mature plant with dried fruit and new stems D flower (top view) E flower (side view) F flower (front view) G inflorescence with peduncle, bract and calyx H calyx (top view) I longitudinal section of calyx showing disc J longitudinal section of corolla showing anterior (lower) lip with fertile stamens K longitudinal section of corolla showing posterior (upper) lips and staminodes (red arrow) L close-up of fertile stamens M ovary and calyx N dried fruits. The coloured plate prepared by Ngọc-Sâm Lý.

Citaion:Tran T-L, Ly N-S, Tran M-N, Nguyen X-T, Cao N-G, Pham H-D (2020) Didymocarpus phuquocensis, a new species of Gesneriaceae from Phu Quoc Island, South-western Vietnam. PhytoKeys 159: 35-44. https://doi.org/10.3897/phytokeys.159.47442