Ming-Tai An’s research while affiliated with Guizhou University and other places

Mallotus bullatus M.T.An & J.H.Yu, sp. nov. (Euphorbiaceae), a species new to science discovered in Guizhou, China, is described and illustrated here, and its phylogenetic position among other Mallotus species is presented. Morphological, micro-morphological, and molecular evidence is presented as attestation of its novelty. The new species morphologically resembles M. philippensis var. reticulatus and M. philippensis var. philippensis, but it clearly differs by having bullate leaf surfaces (vs. not bullate), leaf margins entire or nearly so (vs. entire or nearly so in M. philippensis var. philippensis and coarsely serrate in M. philippensis var. reticulatus), leaf margins sometimes bearing red glands (vs. red glands absent), 5 sepals in staminate flowers (vs. 3–4 in M. philippensis var. philippensis and 4 in M. philippensis var. reticulatus), fruits with spines (vs. spines absent in M. philippensis var. philippensis and present in M. philippensis var. reticulatus), and abaxial leaf epidermal scattered and clustered vein hairs 0.1–0.8 mm long (vs. 0.04–0.28 mm long in M. philippensis var. philippensis and 0.05–0.1 mm long in M. philippensis var. reticulatus). Molecular phylogenetic analysis (BS = 100% / BS = 96%, PP = 1 / PP = 1) provides strong evidence supporting M. bullatus as a new species within the genus Mallotus and supports its placement in M. sect. Philippinenses as sister to M. philippensis.

Salvia penghuana, a new species from Guizhou Province of southwestern China, is described and illustrated. Morphologically, Salvia penghuana is similar to S. filicifolia, but can be easily distinguished from the latter by ovate-lanceolate bracts, purple corolla, and foot-shaped fused lower arms of connective. In addition, S. penhuana is morphologically similar to S. cavaleriei, but differs by having 3–4-pinnate leave, ovate-lanceolate bracts, puberulent calyx, and longer upper arms of connective. Based on the fibril root, small calyx and corolla, and completely reduced posterior thecae, S. penghuana should be placed in section Sobiso of subg. Glutinaria.

Mallotus bullata M.T.An & J.H. Yu sp. Nov. (Euphorbiaceae), a species new to science discovered in Guizhou, China, is described and illustrated here, along with its phylogenetic position among other Mallotus species. Morphological, micro-morphological, and molecular evidence is presented as attestation of its novelty. The new species morphologically resembles M. philippensis var. reticulatus and M. philippensis , but it clearly differs by having leaf surface bullate, absence of coarse serrations on leaf margins, lateral veins reticulate near margins, sepals in male flowers 5, polygamous flowers, pollen grains 3 apertures with have obvious protrusions in the apertures, abaxial leaf epidermal microhairs 1-8 mm long. Molecular phylogenetic analysis (BS = 100% / BS = 96%, PP = 1 / PP = 1) provides strong evidence supporting M. bullata as a new species within the genus Mallotus .

Impatiens beipanjiangensis Jian Xu & H. F. Hu (Balsaminaceae), a new species of Impatiens subg. Clavicarpa discovered in Guizhou, China, is described and illustrated in this study along with its molecular phylogenetic analysis. I. beipanjiangensis is similar to I. liboensis, I. chishuiensis and I. clavigera in morphology, but I. tubulosa has the closest relationship to it. However, there are various ways in which the new species can be easily distinguished from these four species: Inferior nodes swollen rhizoid, pale green and with hooked outer sepals, longer lateral united petals, subovate auricle, deeper lower sepal and shorter spur that is reflexed towards the lower sepal. Furthermore, I. beipanjiangensis is distinguished from other Impatiens species, based on morphological, micromorphological and palynological evidence and molecular data (PP 0.967).

Oxalis xishuiensis , a new species of Oxalidaceae from Danxia landforms of Xishui County, Guizhou, China, is described and illustrated. It is morphologically similar to O. wulingensis by the two lateral leaflets arranged at about 180° angle and oblong pink petals with lilac veins, but clearly differs from the latter by leaflets almost as long as wide, obliquely obcordate lateral leaflets, shorter peduncles, longer capsule (1.2–1.5 cm vs. 0.5–0.7 cm) and alveolate seeds.

Hypericum liboense M.T.An & T.R.Wu, sp. nov. (Hypericaceae) is a newly described species found in the Maolan National Nature Reserve of Guizhou Province, where it grows in rocky habitats without soil on karst mountain tops. In this study, key morphological characters were compared between the new species and the other known Hypericum species of Hypericaceae. DNA sequences were extracted from the leaves of the new species, with nuclear gene sequences (ITS) generated to reconstruct phylogenetic trees and describe its phylogenetic position in relation to other species of Hypericum . Our results show that the proposed new species has the typical characteristics of the genus Hypericum in morphology being similar to Hypericum monogynum , but differing in its sessile and semi-clasped leaves, long elliptical to long circular leaf blades, thickly papery to thinly leathery, with entire and wavy leaf margins. The abaxial side of the leaves is covered with white powder, giving them a grey-white appearance. The main lateral veins of the leaves are 8–15-paired, and the midvein on both sides is convex. The main lateral veins and midvein branch are conspicuous, with tertiary venation forming a network on the leaf surface and appearing prominently sunken. The inflorescences are 1–3-flowered, with a large calyx and conspicuous veins. The molecular phylogenetic analysis (PP = 1.00) provided substantial evidence for the proposition of H. liboense as a new species within Hypericum . Morphological and molecular evidence is presented, corroborating the proposition of the new species, including a comprehensive account of the distinctive morphological attributes of H. liboense , along with its key distinguishing features from similar species.

We examined the niche characteristics and interspecific covariant relationship of main species in Phyllostachys edulis-Alsophila spinulosa association in Chishui A. spinulosa National Nature Reserve under P. edulis disturbance condition, and analyzed the mechanism of competition and coexistence across different species. The results showed that there were 67 species from 53 genera and 40 families in the association. The importance values, Shannon niche breadth index (BS), and Levins niche breadth index (BL) of P. edulis were the largest, indicating its absolute dominant status in association. The importance value and BL of A. spinulosa ranked the second, while BS was the third. There were 190 pairs of 20 main species. The niche overlap between P. edulis and A. spinulosa was the largest, with niche overlap value of 0.64. 71.6% of species pairs had niche overlap of less than 0.2, indicating low niche overlap and high degree of niche differentiation among species. The overall association of main species in association was significantly positive, and the community was relatively stable. The correlation among the main species was not significant, the linkage was not strong, and the species were independent from each other. P. edulis showed significant positive correlation with A. spinulosa, Brassaiopsis glomerulata, Ficus virens, and Mallotus barbatus, while P. edulis showed significant negative correlation with Mallotus philippensis, Cinnamomum glanduliferum, and Machilus gamblei. Niche difference and fitness between P. edulis and natives affected the coexistence and competition among species. Controlling the expansion of P. edulis and limiting the size of species with negative correlation with A. spinulosa could create a favorable living environment for A. spinulosa.

Impatiens yunlingensis S.X. Yu, Chang Y. Xia & J.H. Yu (Balsaminaceae), a species new to science discovered in Yunnan, China, is described and illustrated here, along with its phylogenetic position among other Impatiens species. Morphological, micro-morphological and molecular evidence is presented as an attestation of its novelty. Impatiens yunlingensis is similar to I. delavayi in having coarsely crenate leave margins, bracts in the upper part, ca. 4 / 5 length of the pedicels, saccate lower sepal with shallowly bifid spur, linear capsules, and elliptic-oblong, tuberculate seeds, but differs from I. delavayi with lateral sepals 4 (vs. 2), lateral united petal basal lobes subtriangular (vs. dolabriform), and seeds' surface equipped with tubercular ornamentation mostly covered with grain shaped appendages (vs. glabrous and without grain shaped appendages on the top).

Pogostemon dielsianus (Lamiaceae) was described in 1913 based on a single gathering from northwestern Yunnan of China collected in 1905, and thereafter no further collections were observed until 2019. We rediscovered the rare endemic species in Lushui County, Yunnan. Molecular phylogenetic analyses based on four cpDNA markers (rbcL, rps16, psbA-trnH, and trnL-trnF) and the nuclear ribosomal internal transcribed spacer (ITS) region confirmed its infrageneric placement within subg. Pogostemon. Based on observations of the rediscovered population of P. dielsianus, we updated its morphological description, provided an illustration, and discussed its distribution. Under IUCN criteria, the species was categorized as "Critically Endangered (CR)".

Oreocharis esquirolii, a member of Gesneriaceae, is known as Thamnocharis esquirolii, which has been regarded a synonym of the former. The species is endemic to Guizhou, southwestern China, and is evaluated as vulnerable (VU) under the International Union for Conservation of Nature (IUCN) criteria. Until now, the sequence and genome information of O. esquirolii remains unknown. In this study, we assembled and characterized the complete chloroplast (cp) genome of O. esquirolii using Illumina sequencing data for the first time. The total length of the cp genome was 154,069 bp with a typical quadripartite structure consisting of a pair of inverted repeats (IRs) of 25,392 bp separated by a large single copy region (LSC) of 85,156 bp and a small single copy region (SSC) of18,129 bp. The genome comprised 114 unique genes with 80 protein-coding genes, 30 tRNA genes, and four rRNA genes. Thirty-one repeat sequences and 74 simple sequence repeats (SSRs) were identified. Genome alignment across five plastid genomes of Gesneriaceae indicated a high sequence similarity. Four highly variable sites (rps16-trnQ, trnS-trnG, ndhF-rpl32, and ycf 1) were identified. Phylogenetic analysis indicated that O. esquirolii grouped together with O. mileensis, supporting resurrection of the name Oreocharis esquirolii from Thamnocharisesquirolii. The complete cp genome sequence will contribute to further studies in molecular identification, genetic diversity, and phylogeny.