Senecio ser. Nemorenses Gagnidze (1974: 16)

Fei, Wen-Qun, Li, Hui-Min, Ren, Chen & Yang, Qin-Er, 2021, Nuclear ITS / ETS sequence data indicate the membership of Senecio racemulifer, but not S. acutipinnus and S. graciliflorus, within the genus Jacobaea (Asteraceae, Senecioneae), Phytotaxa 512 (3), pp. 129-146 : 140-141

Senecio ser. Nemorenses Gagnidze (1974: 16)

Type:— Senecio nemorensis Linnaeus (1753: 870) .

= Jacobaea sect. Graciliflorae Sennikov in Sennikov & Averyanov (2008: 98), syn. nov.

Type:— Jacobaea graciliflora (Candolle) Sennikov in Sennikov & Averyanov (2008: 98) [= Senecio graciliflorus Candolle (1838: 365) ].

Notes:—When Sennikov & Averyanov (2008) transferred Senecio acutipinnus and S. graciliflorus to Jacobaea as J. acutipinnus and J. graciliflora respectively, they established J. sect. Graciliflorae to accommodate the two species. Jeffrey & Chen (1984), Chen (1999), and Chen et al. (2011) had previously placed both of them within S. ser. Nemorenses. Since our results indicate that both S. acutipinnus and S. graciliflorus should be retained within Senecio , here we reduce J. sect. Graciliflorae to the synonymy of S. ser. Nemorenses.

Senecio acutipinnus Handel-Mazzetti (1936: 1127) . Jacobaea acutipinna (Hand.-Mazz.) Sennikov in Sennikov & Averyanov (2008: 98), syn. nov.

Type:— CHINA. Yunnan, Longchuan Jiang-Nu Jiang divide (= Shweli-Salwin divide), lat. 25°20′ N, ca. 3400 m, Oct 1917, G. Forrest 16044 (lectotype designated by Jeffrey & Chen (1984: 368): E00385523 !, isolectotype: K000852129 !). Figs. 4 , 5 .

Descrption:—Herbs, perennial, rhizomatous. Shoots semirosulate. Stems solitary or few-fasciculate, weakly trailing below, producing roots and vegetative rosettes from the defoliate nodes, ascending to erect above, 60–150 cm long, unbranched except for the inflorescence, fulvous-puberulous when young.Basal and lower stem leaves withered and shed by anthesis, median stem leaves petiolate, oblong-lanceolate, 4–10 cm long, 2–4 cm broad, runcinate-pinnatipartite into a small, linear-lanceolate, acute terminal lobe and 14–20 oblong-lanceolate or lanceolate, acute, apically mucronulate, entire or obscurely denticulate, basally somewhat contracted lateral lobes, papyraceous, subglabrous adaxially, pallid and sparsely puberulous on the veins abaxially; petioles slender, 1–2.5 cm long, glabrous, exauriculate; upper leaves becoming gradually smaller. Capitula discoid, numerous in terminal compound corymbs, crowded, nodding; peduncles slender, 1–3 mm long, fulvous-puberulous, bearing 2–3 linear-subulate bracteoles. Involucres cylindrical-campanulate, ca. 6 mm long, 1.5–2 mm broad, calyculate; bracts of calyculus 1 or 2, linear-subulate, ca. 2 mm long; phyllaries 5, oblong-linear, ca. 1 mm broad, obtuse, apically dark and on upper margins, herbaceous with narrow scarious margins, glabrous. Disk florets 2–4; corolla orange-yellow, ca. 8 mm long, with 3–3.5 mm long tube and infundibuliform limb; lobes ovate-triangular, 1–2 mm long, acute, apically papillose. Anthers linear, ca. 2 mm long, obtusely shortly auriculate at the base, appendages ovate-lanceolate; anther collars rather elongated, little dilated at the base. Style arms ca. 1.2 mm long. Achenes cylindrical, ca. 2.5 mm long, glabrous. Pappus ca. 6.5 mm long, white. 2 n = 40.

Distribution:— Senecio acutipinnus is distributed in China (western Guizhou, western and southeastern Yunnan) and Vietnam (Lao Chau).

Senecio graciliflorus Candolle (1838: 365) . Jacobaea graciliflora (Candolle) Sennikov in Sennikov & Averyanov (2008: 98), syn. nov. Fig. 6

Type:— INDIA. Kumaon, 1830, R. Blinkworth s.n. in Wall. Cat. 3149/259 A (lectotype designated here: G00329591 !; isolectotypes: BM00035583 !, K000102344 !, P00743055 !, P00743056 !, P00743058 !, PH 00010086!) .

Description:—Herbs, perennial, rhizomatous. Stems solitary, erect, 50–120 cm tall, branching in upper part, sparsely pubescent when young, glabrescent. Leaves petiolate, radical and lower stem leaves withered by anthesis, median stem leaves ovate or ovate-oblong, 10–25 cm long, 6–12 cm broad, pinnatipartite into an oblong-lanceolate, acuminate or acuminate-caudate, terminal lobe and 8–10 oblong-lanceolate, long acuminate, coarsely serrate lateral lobes, papyraceous, sparsely shortly adpressed-pubescent adaxially and especially on main veins abaxially; petioles slender, 2–4.5 cm long, basally somewhat dilated but exauriculate; upper leaves becoming smaller, less deeply divided and with fewer lateral lobes. Capitula obscurely radiate, numerous in terminal and upper axillary compound corymbs; peduncles slender, 3–5 mm long, densely fulvous-puberulous, linear-bracteolate. Involucres narrowly cylindrical, 8–9 mm long, 1.5–2 mm broad, calyculate; bracts of calyculus 4 or 5, linear-subulate, 2–3 mm long, puberulous; phyllaries 5, linear, ca. 8 mm long, ca. 1 mm broad, apically obtuse and puberulous, herbaceous with narrow scarious margins, sparsely minutely puberulous, obscurely 3-veined. Ray florets 1 or 2; corolla yellow, filiform, apically truncate or with a minute ray much shorter than the style arms; disk florets 3 or 4; corolla yellow, ca. 8 mm long, with ca. 3.5 mm long tube and infundibuliform limb; lobes ovate-triangular, ca. 1 mm long, acute, apically papillose. Anthers linear, ca. 2.2 mm long, obtusely auriculate or sagittate at the base, appendages ovate-lanceolate; anther collars rather broad, somewhat dilated at the base. Style arms ca. 1.8 mm long. Achenes cylindrical, ca. 2.5 mm long, glabrous. Pappus 4–5 mm long, white. 2 n = 40.

Distribution:— Senecio graciliflorus is widely distributed in China (Sichuan, Xizang, Yunnan), India (Sikkim), Kashmir, and Nepal. It was also recorded to occur in Malaysia and Vietnam ( Sennikov & Averyanov 2008, Chen et al. 2011), but we did not see any material from these two countries. Jeffrey & Chen (1984), Chen (1999), and Chen et al. (2011) all wrongly recorded this species to occur in Guizhou, China based on a collection (E.E. Maire s.n., E) from Io-chan (= Yao Shan, literally meaning “Medicine Mountain”). This mountain, however, is actually situated in Qiaojia county in northeastern Yunnan.

Notes:—There are some incongruences between the original description and current definition of Senecio graciliflorus . This species was originally described as having radiate capitula with 6 or 7 phyllaries, 3–5 ray florets with oblong ligules, and 5 or 6 disk florets ( Candolle 1838). However, the name is currently applied to a species which has disciform capitula with 5 phyllaries, 1 or 2 filiform female florets, and 3 or 4 disk florets. The problem is caused by the admixture of one of its type gatherings. Senecio graciliflorus has two type gatherings, R. Blinkworth s.n. from Kumaon in northern India (syntype: G00329591; isosyntypes: BM00035583, K000102344, P00743055, P00743056, P00743058, PH 00010086) and N. Wallich s.n. from Gosain Than (= Shishapangma) in Xizang, China (syntype: G00329592; isosyntypes: BM00035584, K000102345, and K000102346), the latter being mixed. The fourth sheet (as indicated by the number “4” at the right top) of G00329592 and the right specimen on the sheet of K000102346 have radiate capitula and match the original description of S. graciliflorus much better. However, they belong to the currently accepted S. royleanus Candolle (1838: 366) . Other elements of N. Wallich s.n., as well as all the specimens of R. Blinkworth s.n., are all characterized by having disciform capitula and thus belong to S. graciliflorus as currently defined.

If Senecio graciliflorus is typified based on the elements better matching its original description, i.e. the fourth sheet of G00329592 or the right specimen of K000102346, it will become conspecific with S. royleanus . Moreover, although S. graciliflorus and S. royleanus were published simultaneously, we cannot synonymize S. graciliflorus with S. royleanus to alleviate the nomenclatural disruption, because Hooker (1881) once reduced S. royleanus to the synonymy under S. graciliflorus , and this treatment needs to be followed. Therefore, this designation will affect two quite stable names which have fairly consistent delimitations and are currently widely accepted in all modern regional and national Floras. In addition, these nomenclatural changes would cause further perplexities, especially to non-taxonomists, because the species to which S. graciliflorus and S. royleanus are currently applied are extremely similar in morphology (differing almost entirely only in some floral features) and often sympatric in distribution (both occurring from Kashmir to Bhutan in western and southern Himalayas). To better serve nomenclatural stability, here we designate the G00329591 sheet of R. Blinkworth s.n. as the lectotype of S. graciliflorus following Recommendation 9A.4 of the Shenzhen Code ( Turland et al. 2018).

Figures

FIGURE 4. Selected specimens of Senecio acutipinnus. A. China, Guizhou, Leishan county, X.L. Yu 14111003 (CSF). B. China, Yunnan, Yongde county, E.D. Liu & Z.F. Xu 3422 (KUN).

FIGURE 5. Senecio acutipinnus in the wild (Wenshan county, Yunnan, China). A. Habitat. B. Habit. C. Rhizome and roots. D. Proximal to distal stem leaves. E. Synflorescence. F. Capitula. G. Phyllaries (abaxial side). H. Disc florets. I. Achene and pappus. Photographed by Wen-qun Fei.

FIGURE 6. Senecio graciliflorus in the wild (Lhünzê, Xizang, China). A. Habitat. B. Habit. C. Rhizome and roots. D. Leaf. E. Synflorescence. F. Capitula. G. Phyllaries (abaxial side). H. Ray florets. I. Disc florets. Photographed by Long Wang.