Semenovia gyirongensis (Apiaceae), a new species from Xizang, China

A peer-reviewed open-access journal PhytoKeys 82: 57–72 (2017) Semenovia gyirongensis (Apiaceae), a new species from Xizang, China doi: 10.3897/phytokeys.82.13010 RESEARCH ARTICLE http://phytokeys.pensoft.net 57 Launched to accelerate biodiversity research Semenovia gyirongensis (Apiaceae), a new species from Xizang, China Qun Ying Xiao1, Jin Bo Tan1, Hao Yu Hu1, Song Dong Zhou1, Xing Jin He1 1 Key laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Science, Sichuan University, 610065 Chengdu, Sichuan, People’s Republic of China Corresponding author: Xing Jin He () Academic editor: P. de Lange | Received 1 April 2017 | Accepted 14 June 2017 | Published 29 June 2017 Citation: Xiao QY, Tan JB, Hu HY, Zhou SD, He XJ (2017) Semenovia gyirongensis (Apiaceae), a new species from Xizang, China. PhytoKeys 82: 57–72. https://doi.org/10.3897/phytokeys.82.13010 Abstract Based on morphology and molecular data, a new species Semenovia gyirongensis Q.Y.Xiao & X.J.He, from Gyirong County, Xizang, China, is described and illustrated. It is morphologically most similar to S. malcolmii (Hemsley & Pearson) Pimenov, but differs in its cylindric much-branched root, intensively branching long underground caudex with distinct nodes, narrowly ovate to ovate terminal leaf lobes, oblong bracts with obtuse-rounded or cuneate apex. Keywords Apiaceae, new species, pollen, Qinghai-Tibetan Plateau, Semenovia, taxonomy Introduction Semenovia Regel & Herder (Apiaceae, tribe Tordylieae), an endemic Asiatic genus, occurs in southwest, central and east Asia, with its center of diversity in the Pamir mountains (Shen 1992; Pimenov and Leonov 1993; Pu and Watson 2005; Ukrainskaja 2015). Most species of Semenovia are narrow endemics and grow mainly in the mid-elevation to highland areas of mountains (Ukrainskaja et al. 2013; Ukrainskaja 2015). The latest revision of Semenovia was conducted by Ukrainskaja et al. (2013), who recognized 29 species. There are 6 species of Semenovia in China, two of which are endemic to Qinghai-Tibetan Plateau (QTP) (Ukrainskaja et al. 2013). Semenovia is a perennial herb with pinnate leaves, entire or branched caudex, unequal (outer ones are Copyright Qun Ying Xiao et al. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. 58 Qun Ying Xiao et al. / PhytoKeys 82: 57–72 (2017) larger) or subequal outer and inner petals, small bracts and bracteoles, well developed styles, thinly and narrowly winged marginal ribs, filiform vittae, solitary vittae per vallecular and two (rarely four) on commissural surface (Regel and Herder 1866; Mandenova 1959; Alava 1987; Pu and Watson 2005). Caudex states (underground, overground or emergent; unbranched or branched; short or long branches) are regarded as the most important diagnostic characters within the genus Semenovia (Ukrainskaja et al. 2013; Ukrainskaja 2015). According to morphological data, the genus Semenovia clearly differs from closely related genera Tordyliopsis DC. (well-developed, broad leafy bracts and bracteoles), Zosima Hoffm. (strongly inflated and broadly winged marginal ribs, dorsal vittae occupying furrows completely), Kandaharia Alava (very short styles, up to 0.5 mm long, strongly inflated and broadly winged marginal ribs, numerous commissural vittae), and Pastinacopsis Golosk (vallecular and commissural vittae obsolete) (Mandenova 1959; Alava 1987; Pimenov et al. 2000; Menemen and Jury 2001; Pu and Watson 2005; Ukrainskaja et al. 2013). During examining specimens of Semenovia, we encountered one collection (Z. Y. Wu et al. 75-0676, stored in HNWP, KUN and PE), which was collected from Gyirong County, Xizang, China and was unable to identify as any described species. In August 2016, we carried out field investigation to the exact locality and gathered both flowering and fruiting plant from the natural population. After thoroughly consulting relevant literatures (e.g. Mandenova 1959; Alava 1987; Vinogradova and Kamelin 1986; Ukrainskaja et al. 2013; Ukrainskaja 2015) and herbarium specimens, as well as comparing this taxon with all described species within the genus, we come to the conclusion that the specimens from Gyirong represent a hitherto undescribed species. Herein a new name Semenovia gyirongensis is proposed, and detailed descriptions and comments of this new species, as well as comparisons with its morphologically similar species are given. Material and methods Specimen examinations, field investigations and morphology observations Related specimens deposited in C, CDBI, HNWP, K, KUN, NAS, PE, SZ, XJA and XJBI were studied. Protologues and images of type specimens were gathered fromTropicos (http://www.tropicos.org), JSTOR Global Plants (http://plants.jstor.org) and the International Plant Names Index (http://www. ipni.org). Herbarium acronyms followed Thiers (2016). Sampling was conducted from type localities of S. gyirongensis (Gyirong County, Xizang) and S. malcolmii (Shuanghu, Nyima County, Xizang) during 2015–2016. Photographs in the field were made using a Nikon D7100 camera. The measurements of the morphological features were conducted using a vernier caliper. Mericarps were photographed using stereomicroscope Nikon SMZ 25 (Japan). Fruits from formalde- Semenovia gyirongensis (Apiaceae), a new species from Xizang, China 59 hyde-acetic acid-alcohol (FAA) preserved material were used in the anatomical study. Pollen was examined from anthers collected directly in the field. The pollen grains were mounted on clean aluminum stubs using conducting carbon adhesive tabs, coated and then scanned with a JSM-7500F scanning electron microscope (SEM). General terminologies for this study followed Kljuykov et al. (2004). Voucher specimens were deposited in the herbarium of Natural History Museum of Sichuan University (SZ). DNA extraction, amplification and sequencing Total genomic DNA was extracted from silica gel-dried leaves and herbarium materials according to the protocols of plant genomic DNA kit (Tiangen Biotech, Beijing, China). The internal transcribed spacer (ITS) and external transcribed spacer (ETS) of nuclear ribosomal DNA (nrDNA) were used for phylogenetic inference based on the previous study (Logacheva et al. 2010). The primer pairs ITS4 / ITS5 (White et al. 1990) and 18S-ETS (Baldwin and Markos 1998) / Umb-ETS (Logacheva et al. 2010) were used to amplify the ITS and ETS regions, respectively. Amplification was carried out in a 30µL volume with 2 µL plant total DNA, 10 µL ddH2O, 1.5 µL forward primer, 1.5 µL reverse primer and 15 µL 2 × Taq MasterMix (cwbio, Beijing, China). PCR cycling profile included a denaturing step at 95 °C for 4 min, followed by 35 cycles of 45 s at 95 °C, annealing at 54 °C for 45 s and extension at 72 °C for 1 min, with a final ex (...truncated)