Delphinium drepanocentrum ( Brühl 1896: 101 ) Munz (1968: 94)

Yuan, Qiong & Yang, Qin-Er, 2022, Taxonomic studies on the genus Delphinium (Ranunculaceae) from China (XXII): Clarifying morphological distinction between D. drepanocentrum and D. umbrosum and synonymizing D. umbrosoides with D. drepanocentrum, Phytotaxa 572 (3), pp. 243-258 : 244-250

publication ID	https://doi.org/ 10.11646/phytotaxa.572.3.3
DOI	https://doi.org/10.5281/zenodo.7328073
persistent identifier	https://treatment.plazi.org/id/BB6E6A41-FFF4-7974-FF12-FDB32452F913
treatment provided by	Plazi
scientific name	Delphinium drepanocentrum ( Brühl 1896: 101 ) Munz (1968: 94)
status

Treatment

Delphinium drepanocentrum ( Brühl 1896: 101) Munz (1968: 94) View in CoL . Figs. 1–5 View FIGURE 1 View FIGURE 2 View FIGURE 3 View FIGURE 4 View FIGURE 5 .

≡ D. altissimum var. drepanocentrum Brühl ex Huth (1895: 419) View in CoL .

≡ D. altissimum subsp. drepanocentrum Brühl (1896: 101) View in CoL .

≡ D. umbrosum subsp. drepanocentrum ( Brühl 1896: 101) Chowdhury ex Mukerjee (1960: 293) View in CoL .

≡ D. drepanocentrum ( Brühl 1896: 101) Tamura (1968: 100) View in CoL .

≡ D. umbrosum var. drepanocentrum (Brühl ex Huth 1895: 419) Wang & Warnock View in CoL in Wang et al. (1995: 385), syn. nov.

Type:— NEPAL. Sankhuwasabha District , towards Wallanchún, G. King’s collectors s.n. (JE00016325!). Fig. 1 View FIGURE 1 .

= D. umbrosoides Wang (2020: 180) View in CoL , syn. nov.

Type:— CHINA. Xizang: Dinggyê (= Dingjie), Chentanggou , Meinühu , alt. 4151 m, moist places at forest margin, 15 July 2013, PE Xizang Exped. 3526 (holotype PE02288889!, isotype PE02288891!). Fig. 4 View FIGURE 4 .

Description:—Perennial herbs. Rootstock thickened, woody. Stems erect, 40–60 cm tall, simple or nearly so, spreading yellowish hispid. Leaves papery; lowest leaves withered by anthesis; proximal and middle leaves long petiolate; petioles 10–20 cm long, densely spreading yellowish hispid, somewhat dilated at base; blades somewhat pentagonal, papery, hispid on both surfaces, 5–10 cm long, 5–8 cm broad, base cordate, (3–) 5-lobed to 1–2 cm from the base, lobes broadly rhombic, base cuneate, incised dentate, or sometimes shallowly 3-lobulate, then dentate; leaves gradually reduced upward, distal ones smaller, shortly petiolate, 3-lobed, the uppermost becoming trifoliolate bracts 2–3 cm long. Inflorescence a terminal, simple and secund raceme, 10–30 cm long, 5–20-flowered, densely spreading yellowish glandular-hispid; upper bracts linear to lanceolate-elliptic, 1–2 cm long; pedicels erect, densely spreading yellowish glandular-hispid, 1–4 cm long; bracteoles distal, oblong-linear, 7–8 mm long, ca. 1 mm broad. Sepals bluepurple, abaxially appressed hispid; upper sepal ovate, 1.2–1.3 cm long, 8 mm broad, obtuse, spur subulate, strongly recurved or merely recurved-spreading, 2–2.2 cm long, base 2.5 mm in diameter, narrowed into a very slender tip; lateral sepals elliptic-oblong, 1.2–1.3 cm long, 5–6 mm broad, apex rounded-truncate; lower sepals asymmetrically oblong-elliptic, 1–1.1 cm long, 5 mm broad, apex rounded. Petals bluish; lamina glabrous, pointed, subentire, spur very slender, ca. 2 cm long. Staminodes oblong, 6.5 mm long, 3 mm broad, 2-lobed; lobes linear-oblong, white or yellowish barbate; claws ca. 5 mm long. Stamens glabrous. Carpels 3; ovaries puberulent. Follicles puberulent.

Distribution and habitat:— Delphinium drepanocentrum is currently known from China (southern Xizang) and eastern Nepal ( Fig. 6 View FIGURE 6 ). It grows on grassy slopes, at forest margins or along stream sides at altitudes of (2800–) 3400–4100 m above sea level. Munz (1965) stated that the type material of this species was collected from western Sikkim and Grierson & Long (1984) recorded the occurrence of this species in Sikkim, but the type material was actually collected from eastern Nepal, not from Sikkim ( Fig. 1 View FIGURE 1 ). We have not as yet seen any authentic material of D. drepanocentrum from Sikkim. According to Gogoi et al. (2021), this species indeed does not occur in Sikkim.

Phenology:—Flowering from late July to September; fruiting from September to early October.

Additional specimens examined (barcodes are given when available):— CHINA. Xizang: Dinggyê, CMTTE 966 (GXMG); Nyalam, Xizang Chin. Trad. Med. Exped. 1554 (HNWP, PE) .

NEPAL. Dolakha District, L. Dhwoj 641 (E), S. Noshiro et al. 20710179 (E); Ramechhap District, H. Ohba et al. 8580473 (E, KATH025854); Sankhuwasabha District, L.W. Beer 10010 (BM), L.W. Beer 25391 (BM), H. Ohba et al. 9153384 (E, KATH021483), T.B. Shrestha & D.P.Joshi 405 (BM), M.N. Subedi 228-1991 (KATH019645); Solukhumbu District, J.H. Haas 2969 (BM), F. Miyamoto et al. 9584270 (E, KATH018985, KATH018986), F. Miyamoto et al. 9592173 (BM, E, KATH019444), F. Miyamoto et al. 9592401 (BM, E), F. Miyamoto et al. 9596217 (KATH022207), F. Miyamoto et al. 9596431 (KATH022206, KUN0137427), F. Miyamoto et al. 9596436 (KATH02220), F. Miyamoto et al. 9596500 (E, KATH019464), M. Wakabayashi et al. 9720162 (E), M. Wakabayashi et al. 9730190 (E, KATH025274), M.F. Watson et al. DNEP3 BX93 (E, KATH006216, KATH095106); Taplejung District, Curzon 81 (K), J.D.A. Stainton 1142 (BM, E), J.D.A. Stainton 1144 (BM, E), KEKE 508 (E); Without precise locality, L.W. Beer et al. 8400 (BM), L. Dhwoj 0191 (BM, E).

Notes:— Huth (1895) described Delphinium altissimum var. drepanocentrum on the basis of a single specimen, G. King’s collector s.n. (JE; Fig. 1 View FIGURE 1 ), from the neighborhood of Wallanchún in Sankhuwasabha District, eastern Nepal ( Fig. 6 View FIGURE 6 ). According to the protologue, this variety was characterized by having sickle-shaped, incurved spur of sepals and hirsute carpels (“calcari falcato-incurvo, carpellis hirsutis”). Based on the same collection, Brühl (1896) published it as a subspecies of D. altissimum , i.e. D. altissimum subsp. drepanocentrum , with an excellent line illustration and a brief description: “a middle-sized herb; the whole stem covered with dirty-yellow more or less deflexed, partly glandular hairs; blade of leaves hairy above, subhirsute beneath; bracteoles close to the flower, linear; sepaline spur longer than the sepals, sickle-shaped; ovaries hirsute”. Munz (1968), in January, without giving any reason, raised D. altissimum subsp. drepanocentrum to specific rank, proposing the combination D. drepanocentrum (Brühl) Munz. Tamura (1968) , in November, also raised D. altissimum subsp. drepanocentrum to specific rank. proposing the combination D. drepanocentrum (Brühl) Tamura. In his remarks, Tamura (1968) stressed that this species was distinguished from D. altissimum mainly by the yellowish indumentum on stem, petioles, both sides of leaves, especially on veins of abaxial surface, pedicels, sepals and carpels. He further elaborated on the morphological distinction between the two species. The hairs in D. drepanocentrum were various in length; some of them were spreading, glandulose and swollen near the base, some of them were curled or deflexed and eglandulose. On the lower part of stem, the hairs were sparse and usually curled, on the pedicels and outside of sepals, they were more dense and partly spreading, and on the carpels subvillose and not spreading. Leaf-lobes were ovate- or obovate-rhombic, regularly laciniate-dentate into the laciniae with obtuse or round tips. Bracteoles were approximate to the flower, flowers 30–38 mm long, and the spurs distinctly longer than the sepals, sickle-shaped or nearly straight. While in D. altissimum , the stem was pubescent but usually glabrous downwards, and the hairs white, curled and eglandulose, though sometimes the hairs on petioles, abaxial side of leaves and carpels were somewhat similar to those of D. drepanocentrum . Sepals were covered with white curled and eglandulose hairs and carpels glabrous or hairy. Bracteoles were usually distant from the flowers, flowers smaller than those of D. drepanocentrum , and spurs usually slightly longer than the sepals, straight or slightly curved. Tamura (1968) stated that D. drepanocentrum was distributed in western Sikkim and eastern Nepal. Hara (1979) and Rau (1993) accepted the specific status of D. drepanocentrum proposed independently by Munz (1968) and Tamura (1968). Tamura’s (1968) combination, published several months later, is an illegitimate isonym and has been rejected.

However, without giving any reason, Mukerjee (1960) transferred Delphinium altissimum subsp. drepanocentrum to D. umbrosum Handel-Mazzetti (1931: 278) as a subspecies, i.e. D. umbrosum subsp. drepanocentrum . This treatment was accepted by Wang (1979) in his account of the genus Delphinium from China in the Flora Reipublicae Popularis Sinicae vol. 27. He noted that this subspecies was different from subsp. umbrosum by having stems shorter, 50–70 cm tall, ca. 6 mm thick (vs. taller, 60–110 cm tall, 5–12 mm thick at base), and densely spreading hirsute, with the hairs 1–3 mm long (vs. retrosely appressed puberulous, with the hairs 0.1–0.9 mm long) and also by having bracteoles 1.5–1.8 mm (vs. 0.5–0.6 mm) broad, and that it was distributed in China (southern Xizang), India (Sikkim) and Nepal. Wang & Warnock in Wang et al. (1995) treated this taxon as a variety, proposing the combination D. umbrosum var. drepanocentrum (Brühl) Wang & Warnock. They noted that this combination was necessitated by the editorial policy of the Flora of China Project to recognize only one infraspecific rank within a genus and that use of variety as the infrageneric rank for the Chinese Delphinium required fewer new combinations than use of subspecies. This treatment was adopted by Wang & Warnock (2001) in their account of the Chinese Delphinium in the Flora of China vol. 6 and by Wang (2020) in his recently published treatise “A revision of the genus Delphinium (Ranunculaceae) of China (II)”.

We agree with Munz (1968) and Tamura (1968) that Delphinium drepanocentrum should be recognized as an independent species of its own. This Himalayan species ( Figs. 1–5 View FIGURE 1 View FIGURE 2 View FIGURE 3 View FIGURE 4 View FIGURE 5 ) is somewhat similar to D. umbrosum ( Figs. 7–9 View FIGURE 7 View FIGURE 8 View FIGURE 9 ) in leaf division and bracteoles distal on the pedicel (close to the flower), but very readily distinguishable by having thicker and papery (vs. thinner and membranous) leaves mostly basal and persistent (vs. mostly cauline, with the basal ones usually having withered) at anthesis, and spreading hirsute (vs. appressed puberulent) stem, petioles, inflorescence axis and pedicels. Geographically, the two species are remarkably disjunctive, with D. drepanocentrum distributed in southern Xizang (Dinggyê, Nyalam), China and Nepal, whereas D. umbrosum endemic to northwestern Yunnan, China ( Fig. 6 View FIGURE 6 ).

Wang (2020) described Delphinium umbrosoides on the basis of a single collection, PE Xizang Exped. 3526 (PE; Fig. 4 View FIGURE 4 ), from Dinggyê (= Dingjie) in southern Xizang, China. In the protologue, the author stated that it was similar to D. umbrosum in having 3-partite leaves, racemose inflorescence, linear bracteoles close to the flower, and sepals shorter than the sepaline spur, but remarkably differed by having shorter plant 11–16 cm (vs. 60–110 cm) tall and 3–4 leaves all basal and persistent (vs. leaves basal and cauline, with the basal leaves having withered at anthesis). Wang (2020) also noted the holotype ( Fig. 4A View FIGURE 4 ) was an abnormally developed plant, with the pedicel of a flower at the base of the raceme strongly elongated while the other parts strongly abbreviated, but the isotype ( Fig. 4B View FIGURE 4 ) was a normally developed plant, with the raceme not yet mature and containing only flowering buds. According to the field record, this collection was made on 15 July , 2014, not yet the usual flowering period of the plant in question. Our specimen survey at GXMG resulted in the discovery of a Delphinium specimen, CMTTE 966 (GXMG; Fig. 5 View FIGURE 5 ), from the exact type locality of D. umbrosoides , i.e. Chengtanggou in Dinggyê , southern Xizang. A comparison of the type specimens of D. umbrosoides with this specimen and those of D. drepanocentrum from Nepal ( Fig. 1 View FIGURE 1 , 2 View FIGURE 2 ) and from Nyalam in southern Xizang ( Fig. 3 View FIGURE 3 ) indicates clearly that D. umbrosoides , which is characterized by, among other characters, having spreading hirsute stem, petioles, inflorescence axis and pedicels, should be conspecific with D. drepanocentrum . We therefore place D. umbrosoides in synonymy with D. drepanocentrum herein.

Some collections from Cona in southern Xizang , China, including Anonymous 75-1841 (PE), PE Xizang Exped. 6282 (PE), Qinghai-Xizang Supplem. Exped. 75-1642 (KUN, PE), Qinghai-Xizang Supplem. Exped. 75-1720 (KUN, PE), and Qinghai-Xizang Veg. Exped. 2471 (PE), have been identified in 1976 and 2017 respectively as Delphinium umbrosum subsp. drepanocentrum on the determination slips (two sheets of the collection PE Xizang Exped. 6282 shown in Figure 10 View FIGURE 10 ), and Wang (2020) cited two of them, Xizang Supplem. Exped. 75-1642 ( Fig. 11A, B View FIGURE 11 ) and Xizang Supplem. Exped. 75-1720 ( Fig. 11C, D View FIGURE 11 ), under D. umbrosum var. drepanocentrum . These collections are indeed somewhat similar to D. drepanocentrum in the position of bracteoles on pedicels (the bracteoles close to the flower), but they differ remarkably by having somewhat deeply divided leaves, more leafy stems, densely appressed strigose stems, petioles, inflorescence axis and pedicels, and sparsely pubescent or subglabrous follicles. They should belong to a hitherto undescribed species. In addition, Wang (2020) referred another collection from Cona, PE Xizang Exped. 6212 (PE), to D. conaense Wang in Wang & Li (1987: 34). This collection should also belong to the hitherto undescribed species while D. conaense is certainly conspecific with D. bhutanicum Munz (1967: 507) , a species hitherto recorded to occur only in Bhutan ( Grierson 1984). Geographically Cona is closely adjacent to eastern Bhutan. We will report these two species and place D. conaense in synonymy with D. bhutanicum elsewhere.