﻿Morphological and molecular evidence reveals three new species of Lithocarpus (Fagaceae) from Bidoup-Nui Ba National Park, Vietnam.

Yoshihisa Suyama,Nguyen Van Ngoc,Hoang Thi Binh,Ayumi Matsuo,Tetsukazu Yahara,Ai Nagahama,Shuichiro Tagane,Hironori Toyama

doi:10.3897/phytokeys.186.69878

Abstract

Three new species, Lithocarpusbidoupensis Ngoc & Tagane, L.congtroiensis Ngoc & Yahara, and L.hongiaoensis Ngoc & Binh are described from Bidoup-Nui Ba National Park, Central Highland of Vietnam. Morphological analyses and Maximum likelihood tree based on genome-wide SNPs support the distinction of those species from the previously known taxa in the region. The three new species are considered to be endemic to the Bidoup-Nui Ba National Park and the preliminary conservation status for each species is evaluated as Critically Endangered.

Highlights

Fagaceae are highly diversified in Vietnam and 216 species of 6 genera have been reported in various forest types, from dry evergreen forest at lowlands to montane evergreen forest in the higher elevation (Ho 2003; Ban 2005; Ngoc et al 2016)
L. bidoupensis significantly differed in much shorter petioles (0.5 ± 0.1 cm long in L. bidoupensis vs. 1.89 ± 0.23 cm long in L. blaoensis), shorter leaf blades (9.74 ± 1.12 cm long vs. 13.66 ± 1.89 cm long), bigger cupules (0.98 ± 0.19 cm high, 2.47 ± 0.2 cm in diam. vs. 0.64 ± 0.06 cm high, 1.58 ± 0.11 cm in diam.) Lithocarpus bidoupensis has a larger scar of the nut than L. blaoensis (1.4–1.9 cm in diam. vs. 1–1.2 cm in diam.)
Lithocarpus bidoupensis is most similar to L. blaoensis that occurred in the same locality with L. bidoupensis, and similar to L. licentii that was collected in Kon Tum Province, which is the type locality of L. licentii

Summary

Introduction

Fagaceae are highly diversified in Vietnam and 216 species of 6 genera have been reported in various forest types, from dry evergreen forest at lowlands to montane evergreen forest in the higher elevation (Ho 2003; Ban 2005; Ngoc et al 2016). The previous taxonomic treatments of Lithocarpus in Vietnam were mostly based on Camus’ studies using the specimens collected by French botanists, the results of which were documented in the part of Flore générale de l’Indo-Chine (Hickel and Camus 1930) or Chênes Atlas (Camus 1948). All these early studies relied only on morphological features to identify and construct the keys to species level, so the taxonomic circumscriptions were sometimes inaccurate, leading to continued uncertainty in the taxonomic status and relationship among species. We applied MIG-seq for phylogenetic reconstruction to accurately assess the diversity and taxonomy of Lithocarpus species

Methods

Results

Conclusion