Research Article |
Corresponding author: Biao Yang ( yangb315@163.com ) Academic editor: Bing Liu
© 2024 Xinqiang Song, Boni Song, Mingxia Fu, Jiacai Wang, Jingyi Liu, Weirui Qin, Yuzhou Jiang, Leni Fan, Biao Yang.
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.
Citation:
Song X, Song B, Fu M, Wang J, Liu J, Qin W, Jiang Y, Fan L, Yang B (2024) Impatiens yingjingensis (Balsaminaceae), a new species from Sichuan, China. PhytoKeys 242: 293-306. https://doi.org/10.3897/phytokeys.242.119702
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This study describes Impatiens yingjingensis X.Q. Song, B.N. Song & Biao Yang, sp. nov., a new species collected from the Yingjing area of the Giant Panda National Park. This new species is distributed at an altitude of 1400–2100 m, with a plant height of 30–130 cm. The flowers are purple-red or light purple red, with 3–9 flowers on each inflorescence and the dorsal auricle of the lateral united petals is thread-like and about 2 cm long, differing significantly from other species of Impatiens. Furthermore, molecular data, as well as micro-morphological evidence under SEM (of pollens), also support the establishment of the new species.
Balsaminaceae, Giant Panda National Park, Impatiens, new species, Yingjing County
The genus Impatiens L. is the largest genus in the family Balsaminaceae, with more than 1,000 species (
In recent years, several new species and new records of this genus, including I. longiaristata, I. tripetala, I. wawuensis, I. longlinensis, I. wutaishanensis, I. longshanensis, I. lihengiana and I. cavaleriei have been discovered in southwest China (
The Yingjing area of the Giant Panda National Park (GPNP) is located in Yingjing County, Sichuan Province, spanning a total area of 836 km2. It is situated in the mountainous area transitioning from the Sichuan Basin to the Qinghai-Tibet Plateau. The unique geographical position, varying altitudes and distinct climate conditions have given rise to a diverse array of flora and fauna, fostering complex ecological communities within the vicinity (
Fresh plant material of the unidentified Impatiens species was collected from the Mount Yunwu area of Yingjing County, within the GPNP. The location was at Shaidianping (29°33.98'N, 102°45.00'E, 1624 m alt.). The collected specimens were deposited at the Herbarium of Sichuan University (Chengdu, China). Following the guidelines of Flora Reipublicae Popularis Sinica, Balsaminaceae, Tomus 47 (part 2) (
The fresh adult basal leaves of this species were collected in the field and then dried immediately with silica gel for the next step. Voucher specimens were stored at the Herbarium of Sichuan University (Chengdu, China) under deposition number 202108001. Firstly, we extracted the total genomic DNA from silica-dried leaves with a plant genomic DNA kit (Cwbio Biosciences, Beijing, China) referring to the manufacturer’s protocols. Then, the quality and quantity of extracted DNA were tested using 1% agarose gel electrophoresis and high-quality DNA was sequenced on Illumina NovaSeq platform at Personalbio (Shanghai, China) according to the standard Illumina sequencing protocols (
In addition, total genomic DNA was also employed to amplify the Internal Transcribed Spacer (ITS) regions and the 30 µl amplification system was performed, which included 2 µl extracted total DNA, 10 µl ddH2O, 15 µl Taq MasterMix (CWBio, Beijing, China), 1.5 µl of 10 pmol µl−1 forward primers ITS4 (5’-TCC TCCGCT TAT TGATAT GC- 3’) and 1.5 µl of 10 pmol µl−1 reverse primers ITS5 (5’-GGA AGTAAA AGTCGT AAC AAG G-3’ (
The plastome of this species was de novo assembled by NOVOPlasty v.2.6.2 (
To investigate the phylogenetic position of this species, 62 complete plastome data and 62 ITS sequences were employed to reconstruct the phylogenetic trees, and Hydrocera triflora was selected as outgroup (Suppl material
We investigated carefully the morphology of this new species and observed that its distinctive morphological features are its flower, inflorescences, dorsal petal, lower petal, lateral united petals and lower sepal, such as it has purple-red or light purple-red flowers with 7–12 pairs of lateral veins. The inflorescences are axillary, slightly shorter than the leaf length or approximately equal to the leaf blade in length, 3–9 flowered arranged in a one-sided raceme on the inflorescence axis. The dorsal petal is orbicular approximately 15 mm in diameter, with a concave apex and obtuse tip, the mid-vein on the back thickening with narrow wings, wings 2-angled. The lower petal is gradually narrowing at the base into a sickle-shaped spur approximately 2 cm long; lateral united petals 2-lobed, auricle linear approximately 2 cm, elongate, inserted into spur (Fig.
Comparative morphological characters of I. yingjingensis and related species.
Characters | I. yingjingensis | I. siculifer | I. drepanophora | I. lateristachys | I. imbecilla | I. faberi |
---|---|---|---|---|---|---|
Plant height (cm) | 30–130 | 30–60 | 100 | 40–100 | 40–60 | 60–70 |
Leaf shape | ovate or elliptic | ovate-lanceolate or elliptic-lanceolate | ovate-lanceolate | obovate-lanceolate | ovate or ovate-oblong | ovate-lanceolate or elliptic |
Leaf length (cm) | 5–22 | 5–13 | 6–13 | 0.5–15 | 5–11 | 5–15 |
Leaf width (cm) | 3.5–7 | 2.5–5 | 2–4 | 6 | 2.5–4 | 2.5–4.5 |
Length of petiole (cm) | 0.5–4 | 1.5–3 | 5 | 2–4 | 2–4 | |
Lateral veins | 7–12 | 5–11 | 7–9 | 6–8 | 5–8 | |
Inflorescence | unilateral cyme | cyme | cyme | unilateral cyme | ||
Pedicel length | 12–29 | 15–20 | 10–20 | |||
Flower | 3–9 | 5–8 | 3–6 | 2 | 2 | |
Bracts | base, lanceolate | base, lanceolate | base, ovate-lanceolate | base, 2mm | ovate-lanceolate, 3–5mm | lanceolate, 2–3 mm |
Flower colour | purple-red or light purplish-red | yellow | yellow | red, light red or white | light red | purple-red |
Dorsal petal | orbicular, 15 mm, with a concave apex, the mid-vein on the back thickening with narrow wings, 2-angled | nearly circular, with the mid-rib on the back thickening into narrow wings | orange-yellow, slightly stalked | 1.5–1.8 cm, top concave, with a blunt pointed head, deeply bifid at the base, the mid-vein on the back thickening with narrow wings, 2-angled | 7–8 mm, with 2 shallow clefts at the top, the mid-rib on the back thickened, with a cockscomb-like projection | orbicular, 13–17 mm, concave or 2-cleft at the top, blunt, deeply bifid at the base, with thickened mid-rib on the back, with wings |
Lateral united petals | 2-lobed, auricle linear, 2 cm long, inserted into spur | 2-lobed | 2-lobed | auticula dorsalis in filum 1–1.5 mm latum, 1–1.3 cm long | 2-lobed, auticula dorsalis in filum | 2-lobed, auticula dorsalis in filum |
Lower sepal | sickle-shaped, the eaves are boat-shaped, and the mouth is flat | narrowly funnel-shaped, with a beak-like short point at the apex | upper edge of the lip petal has a green elongated lobe | angular, 2.5–3 cm long, with an oblique blunt mouth | 12–15 mm long; the mouth is oblique and tapering towards the tip, narrowing downwards | angular, 3–4cm, mouth is oblique, with a small point, bending inwards or straight from the middle |
Spur | sickle-shaped spur, 2cm | introrse or extrorse stamens | long spirally inwardly curved | straight | straight or sickle-shaped | |
Lateral sepals | ovate, 2–4 × 2 mm, with a pointed apex | narrowly elliptic, with an acute apex | sickle-shaped, 2 mm long, light green | diamond-shaped, about 2 mm long, with a truncated base and three veins | oval-shaped, 4 × 1.5–2 mm, with a long tapering tip at the top | green, egg-shaped, 6–8 × 3–5mm, with 3–5 veins and a thickened mid-rib |
Flowering period | July to October | May to October | August | August to September | August to September | |
Capsule | clavate | clavate | clavate | clavate, 2.5–3 cm | Narrow linear , 2.5–3 cm |
In further investigation of this species, we also observed its micromorphology of pollen grains under the scanning electron microscope. The results showed that the pollen grains of this species had a unique micromorphology, characterised by single-grain pollen with a flattened spherical shape. Its polar view was capsule-like, irregular and reticulated (Fig.
This species exhibited a typical quadripartite structure (Fig.
Category of Genes | Group of gene | Name of gene |
---|---|---|
Self-replication | Ribosomal RNA genes | rrn4.5, rrn5, rrn16, rrn23 |
Transfer RNA genes | trnC-GCA, trnD-GUC, trnE-UUC, trnF-GAA, trnG-GCC, trnG-UCC*, trnH-GUG, trnI-CAU, trnK-UUU*, trnL-CAA, trnL-UAA*, trnL-UAG, trnM-CAU, trnP-UGG, trnQ-UUG, trnR-UCU, trnS-GCU, trnS-GGA, trnS-UGA, trnT-UGU, trnT-GGU, trnV-GAC, trnV-UAC*, trnY-GUA, trnW-CCA, trnfM-CAU, trnA-UGC*, trnI-GAU*, trnN-GUU, trnR-ACG | |
Ribosomal protein (small subunit) | rps2, rps3, rps4, rps7, rps8, rps11, rps12**, rps14, rps15, rps16*, rps18, rps19 | |
Ribosomal protein (large subunit) | rpl2*, rpl14, rpl16*, rpl20, rpl22, rpl23, rpl32, rpl33, rpl36 | |
RNA polymerase | rpoA, rpoB, rpoC1*, rpoC2 | |
Translational initiation factor | infA | |
Genes for photosynthesis | Subunits of photosystem I | psaA, psaB, psaC, psaI,psaJ, ycf3**, ycf4 |
Subunits of photosystem II | psbA, psbB, psbC, psbD, psbE, psbF, psbH, psbI, psbJ, psbK, psbL, psbM, psbN, psbT, psbZ | |
Subunits of cytochrome | petA, petB*, petD*, petG, petL, petN | |
Subunits of ATP synthase | atpA, atpB, atpE, atpF*, atpH, atpI | |
Large subunit of Rubisco | rbcL | |
Subunits of NADH dehydrogenase | ndhA*, ndhB*, , ndhC, ndhD, ndhE, ndhF, ndhG, ndhH, ndhI, ndhJ, ndhK | |
Other genes | Maturase | matK |
Envelope membrane protein | cemA | |
Subunit of acetyl-CoA | accD | |
Synthesis gene | ccsA | |
ATP-dependent protease | clpP** | |
Component of TIC complex | ycf1 | |
Genes of unknown function | Conserved open reading frames | ycf2, ycf15 |
We employed 62 complete plastomes and 62 ITS sequences to reconstruct the phylogeny of this new species. Although the plastome data and ITS sequence yielded incongruent tree topologies, both strongly supported the fact that this new species clustered with other Impatiens members, belonging to the genus Impatiens. In the plastome-based and ITS-based phylogenetic tree, the results of the Maximum Likelihood (ML) and Bayesian Inference (BI) analyses generated well-resolved topologies and the topologies were highly identical as expected (Fig.
Phylogenetic trees constructed by Maximum Likelihood (ML) and Bayesian Inference (BI). The bootstrap values (BS) of ML and posterior probabilities (PP) of BI are listed at each node. (*) represents the node with PP = 1.00/BS = 100. “–“ means the values < 0.50/50. Red background indicates the newly-sequenced unknown Impatiens species A plastomes-based tree B ITS-based tree.
China is recognized as a significant hotspot for the distribution of Impatiens. It offers a variety of habitat conditions for the genus Impatiens and breeds a variety of Impatiens resources, including regional endemics and Chinese-specific varieties. Due to the complexities associated with collection and identification, there is a lack of comprehensive and in-depth floristic surveys for the genus Impatiens in China. As a result, the resource status and phylogenetic relationships of the genus Impatiens in China, especially in key and vulnerable areas, are still unclear. Therefore, strengthening the floristic surveys and specimen collection of the Impatiens genus, especially in these critical and vulnerable regions, is an important task for the current research in taxonomy and floristics.
Through the investigation and research of the genus Impatiens in the Yingjing area, it has been found that the distribution points and population numbers of I. yingjingensis are relatively small, mainly being found in the valley, forest edge and roadsides at altitudes of 1400–2100 m in the areas of Mount Yunwu. Surveys and protection have not received adequate attention and it is essential to strengthen the investigation of the local resources of I. yingjingensis and conduct systematic research on the species diversity of the genus Impatiens in Yingjing County.
Through field observation and literature review, I. yingjingensis was found to bear the closest morphological resemblance to I. lateristachys, I. drepanophora, I. siculifer, I. imbecilla and I. faberi. However, their distinct differences were noted. The key features that distinguish I. yingjingensis and I. lateristachys are lower sepal and lateral sepals. Lower sepal in I. yingjingensis is sickle-shaped, the leaves are boat-shaped and the mouth is flat, while the lower sepal in I. lateristachys is angular with an oblique blunt mouth. The lateral sepals in I. yingjingensis are ovate with a pointed apex, while the ones in I. lateristachys are diamond-shaped with a truncated base and three veins, about 2 mm long. The most notable feature that distinguishes I. yingjingensis from I. drepanophora and I. siculifer is flower colour. I. yingjingensis has purple-red or light purplish-red flowers, whereas the flowers in I. drepanophora and I. siculifer are yellow. In addition, I. yingjingensis can be easily distinguished from I. imbecilla by the bracts. Bracts in I. yingjingensis are lanceolate, while I. imbecilla has ovate-lanceolate bracts. Additionally, the dorsal petal between I. yingjingensis and I. imbecilla is also different., The dorsal petal of I. yingjingensis is 2-angled, orbicular with a concave apex and the mid-vein on the back thickening with narrow wings, whereas two shallow clefts at the top, the mid-rib on the back thickened and a cockscomb-like projection of dorsal petal are observed in I. imbecilla. I. yingjingensis can be clearly distinguished from I. faberi by their lateral sepals. The ovate lateral sepals with a pointed apex are detected in I. yingjingensis, but green, egg-shaped and a thickened mid-rib of lateral sepals with 3–5 veins are found in I. faberi (Table
Although the explicit systematic position of I. yingjingensis remains undefined, both phylogenetic trees based on plastome data and ITS sequences, strongly supported that I. yingjingensis is nested within the genus Impatiens, indicating its affiliation with the genus. Consistent with
Impatiens yingjingensis can be distinguished by the following morphological features from related species of Impatiens: purple-red or light purple-red flowers; inflorescence with 3–9 flowers; lower petal gradually narrowing at the base into a sickle-shaped spur approximately 2 cm long; lateral united petals 2-lobed, auricle linear approximately 2 cm, elongate and inserted into spur.
The species is named after Yingjing County, Sichuan Province, China, which is the type locality. The Chinese name is given as “荥经凤仙花”.
Herbs annual, 30–130 cm tall, glabrous, stems fleshy, erect or ascendant, branched, basal nodes swollen adventitious roots. Leaves alternate, petiolate or subsessile on upper stem; leaf blades ovate-oblong, 5–22 × 3.5–7 cm, membranaceous, abaxially puberulent, with 2 stipitate glands at base, base cuneate, margin crenate, apex acuminate; lateral veins 7–12 pairs, petioles 0.5–4 cm long. Inflorescences axillary, slightly shorter than the leaf length or approximately equal to the leaf blade in length, unilateral cyme, 3–9 flowers; pedicels 12–29 mm long, with bracts above base; flowers relatively large, purple-red or light purple-red, 2–3.5 cm long; lateral sepals ovate, ca. 3 × 2 mm, entire, apex acuminate, mucronulate; dorsal petal orbicular, approximately 15 mm in diameter, with a concave apex and obtuse tip, the mid-vein on the back thickening with narrow wings, wings 2-angled; lower petal sickle-shaped, 2.5 cm long and the mouth is flat, gradually narrowing at the base into a sickle-shaped spur, approximately 2 cm long; lateral united petals 2-lobed, the lower lobe approximately 0.5 cm long, the upper lobe oblong and approximately 1 cm long, auricle linear and approximately 2 cm, elongate, inserted into spur. Capsule clavate, 2–5 cm long, hairless. Seed ellipsoid, dark brown to black (Figs
The flowering period is from July to October and the fruiting period is from August to November.
I. yingjingensis is distributed in Yingjing County, Sichuan Province, China, at altitudes of 1400–2100 m.
(paratypes). China. Sichuan: Yingjing County, at the forest edge and in valleys, 29°36.76'N, 102°44.23'E, 1534 m alt., 24 August 2022, P. Liang & L.J. Zhang 202208001, P. Liang & L.J. Zhang 202208002, P. Liang & L.J. Zhang 202208003, P. Liang & L.J. Zhang 202208004, P. Liang & L.J. Zhang 202208005, P. Liang & L.J. Zhang 202208006 (SZ).
The authors have declared that no competing interests exist.
No ethical statement was reported.
No funding was reported.
Investigating: XS, MF, JW, JL, WQ, YJ, LF. Writing-original draft: XS, BS, BY. Writing-review and editing: XS, BS, BY.
Xinqiang Song https://orcid.org/0009-0008-9818-2493
Biao Yang https://orcid.org/0000-0002-2181-8640
All of the data that support the findings of this study are available in the main text or Supplementary Information.
Plastomes data and ITS sequence included in phylogenetic analyses with GenBank accession
Data type: xlsx