A comprehensive evaluation of the diagnostic characters employed in distinguishing Ferula groessingii from F. licentiana var. tunshanica has led to the conclusion that the two taxa are indeed conspecific. As a result, F. groessingii is hereby recognized as a new synonym of F. licentiana var. tunshanica. This reclassification is supported by a comprehensive comparison of taxonomic features, morphological evidence, and distribution data. The study confirms that key morphological traits including plant height, a hairy coat of stems and leaves, number of inflorescences, and fruit vittae, are critical for the identification of this species complex.

Apiaceae, China, Ferula, new synonym, taxonomy

Ferula L. is one of the largest genera in the Apiaceae family, encompassing approximately 220 species globally (https://powo.science.kew.org/results?q=ferula). It is mainly distributed in the southern part of Europe, Northern Africa, Central Asia, and the Mediterranean region, with Central Asia being the biodiversity hotspot of this genus (Pimenov and Leonov 1993).

Ferula groessingii Riedl & Riedl-Dorn was originally described as a new species endemic to China based on a single fruiting collection made by Licent from Taiqinggong in Qingdao, Shangong Province (Fig. 1). In the protologue, Riedl and Riedl-Dorn (1987) compared F. groessingii with F. bungeana Kitagawa (1956) and F. rigidula Candolle (1830), but they overlooked F. licentiana Handel-Mazzetti (1933) and F. tunshanica Anon. (Jiangsu Institute of Botany 1982), which are distributed in Shanxi, Shaanxi, Henan, Hebei, Hubei, Shandong, Anhui and Jiangsu provinces of China (Fig. 3). Furthermore, since its publication, the name has not received attention and was not included in the Flora Reipublicae Popularis Sinicae (Shen 1992) or in the Flora of China (She and Watson 2005). The name F. groessingii reappeared only in Pimenov’s checklist of the Apiaceae in China (Pimenov 2017). However, for the 30 years following its publication, no other literature mentioned this species name.

Figure 1. 

The holotype specimen of F. groessingii (https://www.jacq.org/detail.php?ID=191435).

During our studies and exploration of the specimens of Ferula in China, we found that F. groessingii is morphologically very similar to F. licentiana var. tunshanica. The objective of this study is to confirm the relationship between F. groessingii and F. licentiana var. tunshanica.

We collected specimens of Ferula groessingii from the type locality in 2023 to 2024. These specimens were deposited at the Herbarium of Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences (XJBI). For the detailed collection information, including coordinates, please refer to the “Specimens examined” section. We carefully checked and studied the specimens from NAS and PE in person, while materials from KUN and WUK were examined through photographs on the Chinese Virtual Herbarium (CVH) website (https://www.cvh.ac.cn/index.php). We also conducted detailed comparisons of F. licentiana var. tunshanica plant images available on the Plant Photo Bank of China (PPBC) website (https://ppbc.iplant.cn/sp/24536). Photographs were taken in the field using a Nikon Z7 II camera. Hairs in the stems and leaves were examined using a dissecting microscope Phenix XTL-165 in the laboratory. In order to prepare tissue sections, the mature fruits were softened before being embedded in paraffin. Following staining, the sections were mounted with neutral balsam, observed under a microscope, and photographed for analysis. Additionally, we compared the protologue of F. groessingii with our observed results.

We found a clear resemblance between F. groessingii and F. licentiana var. tunshanica (Figs 1, 2, Table 1). Field sampling conducted at the type locality of F. groessingii and its detailed comparisons with F. licentiana var. tunshanica revealed that its characters are nearly identical. Key diagnostic morphological features such as the plant being glabrous throughout, with an average height of about 2 m, a solitary and slender stem, as well as the morphology of the inflorescence and fruit vittae were found to be consistent between two taxa (She and Watson 2005). The distribution of F. groessingii matches completely with that of F. licentiana var. tunshanica. The latter is predominantly found on sunny mountain slopes in Shandong, Anhui and Jiangsu provinces (Fig. 3). Consequently, based on these findings, we propose F. groessingii be treated as a synonym of F. licentiana var. tunshanica.

Figure 2. 

Morphology of F. groessingii A habitat B basal leaves C inflorescence D individual E flowering stage F cauline leaves G mericarps, dorsal and commissural aspects H cross section of mericarp: (a) median rib, (b) lateral rib, (c) marginal rib, (d) endosperm, (e) vallecular vitta, (f) commissure vitta. Scale bar: 1 mm.

Figure 3. 

Distribution of F. licentiana, F. licentiana var. tunshanica and F. groessingii. The map is based on a standard map downloaded from the National Natural Resources Ministry’s Standard Map Service website. The boundaries of the base map have not been modified.

The scientific name F. licentiana var. tunshanica has an intriguing taxonomic backstory. It was initially published as F. tunshanica Su in the Flora of Jiangsu (Vol. 2: 935. 1982), where “Su” was explicitly stated to represent a collective author (Jiangsu Institute of Botany). Subsequent treatments, whether the invalid reduction to a variety by Liu et al. (1987) or the inadvertent valid publication (Shen 1992; Yu et al. 2010), correctly cited the name authorship. However, in the Flora of China (She and Watson 2005), “Su” was mistakenly interpreted as referring to Song-Wang Su (S.W. Su) who confirmed not to be the author of this taxon, a misinterpretation that has persisted to this day. With no traceable natural person attributable to the name and in accordance with ICN 2018 Art. 46.9 Ex. 45, the correct citation for F. tunshanica should be Ferula tunshanica Anon. (in Fl. Jiangsu 2: 935. 1982).

Our sincere thanks to the staff of NAS, W, XJBI, KUN, WUK, PE, CVH and PPBC for their help in specimen examination and Dr. Hafiz Muhammad Wariss for modifying the English in this article.