HARVARD PAPERS IN BOTANY 4(1): 322-326.
Alexei K. Skvortsov
Main Botanic Garden, Russian Academy of Sciences, 127276 Moscow, Russia.
Abstract. Among collections in the herbarium of the Arnold Arboretum (A), I detected and here describe two new species of Salix (Salicaceae): S. cacuminis from North Korea and S. bouffordii from Yunnan.
Keywords: Eastern Asia, morphology, North Korea, Salicaceae, Salix, taxonomy, Yunnan.
While studying specimens of Salix L. for the Flora of China Project in the collections of the Arnold Arboretum (A) and the Kunming Institute of Botany (KUN), I found specimens of two apparently yet undescribed species.
Salix cacuminis A. Skvortsov sp. nov. (sect. Myrtosalix Kern.). TYPE: NORTH KOREA. Provincia, N. Kankyo, Montes Setsurei (1300--2310 m) ad et prope cacuminem, 26 Aug. 1917. E. H. Wilson 9023 (A). Fig. 1.
Frutex humilis squarrosus. Rami breves fusci glabri, ramuli novelli pills longis irregulariter longitudinalibus vestiti. Gemmae maturae ovatae apice acuto, carinis lateralibus inconspicuis, 3--5 min longi, primo pilis longitudinalibus vestitae, dein glabrescentes lucidae rubescenti-brunneae. Folia petiolis 2--5 mm longis sulcatis, stipulis parvulis (2--3 mm lg.) lanceolatis leviter curvatis apice glandulis 1--3; lamina obovata., apice obtusata v. rotundata, ad 45 x 20 mm magna, margine integerrima, superne et ad margines primo pilis mollibus vestita, dein glabrescens, subtus glabra glaucescens.
Amenta mascula non visa. Feminea pedunculis crassis 6--15 mm longis suffulta, pedunculi cataphyllis paucis parvis subtus villosis instructi. Bracteae nigrescentes utrinque pilis irregulariter longitudinalibus vestitae. Nectarium 1 ovatum v. quadrangulare ad 0.7 mm longum. Capsulae subsessiles ovato-lanceolatae ca. 5 mm longae in stylum sensim abeuntes, primo pilis taeniatis undulatis v. crispulis iridescentibus vestitae, dein (in parte superiore saltem) glabrescentes. Stylus ad 1 mm longus, ad medium vel supra bifidus, stigmata 0.2--0.4 mm longa bifida.
Habitatio: In montibus Koreae Septentrionalis, e loco unico adhuc reperta.
Affinitas. E speciebus sect. Myrtosalix praecipue S. saxatili Turcz. et S. khokhriakovii A. Skvortsov affinis, sed sine dubio ab ambas sat distincta. S. saxatilis differt a nostra specie foliis vulgo minoribus ellipticis acutis, margine minute denticulatis; amentis longioribus strictissimis cum bracteis nigris reflexis et pilis longis strictis obsitis; capsulis distincte pedicellatis tenuioribus. S. khokhriakovii autem differt habitu depresso, foliis minoribus vulgo estipulatis glaberrimis, illis anni praecedentis emarcidis ad ramulis persistentibus.
Sect. Myrtosalix is a well-circumscribed natural group, consisting of 12 to 15 species inhabiting arctic-subarctic and alpine-subalpine regions of northern Eurasia and North America. Members of the section are low or prostrate, or even creeping shrubs. In China, representatives of the section (Salix berberifolia Pallas and S. rectijulis Ledeb.) can be found only in the Altai Mountains. Discovery of a new member of the section in Korea is interesting, especially because the mountains of North Korea are already known to possess widely disjunct stations for several boreal and alpine Siberian willows, namely, Salix nummularia Anderss. (from Korea, described as S. vulcani Nakai), S. divaricata Pallas (described as S. orthostemma Nakai and S. metaformosa Nakai), S. berberifolia Pallas, and S. jenisseensis (Fr. Schmidt) Flod. (described as S. rectispica Nakai ex Flod).
Wilson’s specimen 9023 has been kept at A under the name Salix orthostemma Nakai. But the latter (being a local race of S. divaricata) clearly belongs to sect. Arbuscella. The safest diagnostic difference is in the character of pubescence. The upper surface of the leaves (especially the younger ones) in Salix cacuminis is provided with long, very thin, and disorderly disposed hairs, whereas the leaves of S. divaricata are glabrous or (rarely) with straight silky hairs. The pubescence of the capsules in S. cacuminis consists of rather disorderly wavy or curly hairs, looking gray when seen without magnification but beautifully iridescent when inspected under a strong lens, and rather fugitive. In Salix divaricata (as in other species of sect. Arbuscella), the ovaries are fully or partly covered with straight adpressed hairs, not iridescent and not lost while capsules ripen.
Besides the specimen Wilson 9023, I did not find further specimens of S. cacuminis, at least in A, PE, KUN, and LE.
Salix bouffordii A. Skvortsov sp. nov. (sect. Eriostachyae Schneid.). TYPE: REIPUBLICA POPULARIS SINICA. Provincia Yunnan, Yangbi Xian, Diancang Shan (latus occid.), prope Dajiuping, ca. 3400 m, 30 Junio 1984. Expeditio Botanica Sino-Americana 642 (collectores B. Bartholomew, D. E. Boufford, H. W. Li, C. G. Ma, D. H. Nicholson, T. S. Ying, S. W. Yu). (Holotype: A; Isotype: KUN, MHA). Fig. 2.
Frutex erectus (ad 70 cm altus) ramosissimus. Ramuli anni praecedentis glabri griseo-brunnei, ramuli novelli dense breviter subadpesse pilosi. Folia petiolis 2--5 mm longis pilosis, stipulis minutis dissectis glandulosis; lamina ad 50 x 20 mm magna obovata v. oblanceolata (latitudine maxima in parte superiore), apice subacuta v. obtusata, margine prope apicem dentulis parvulis paucis, supra plana primo adpresse pilosa dein plus-minusve glabrescens, subtus nervis lateralibus 7--11 paribus prominentibus pubescentia conspicue argyracea pulchre notatis.
Amenta mascula non visa. Feminea serotina pedunculos 10--30 min longos foliis parvis 2--5 instructos terminantia, submatura ad 45 mm longa., pedunculo proprio longiora. Bracteae pallidae v. dilute castanei v. leviter purpurascentes, ca. 1.4--1.8 x l.0 mm dimetientes, apice rotundatae v. retusae v. emarginatae, utrinque facie breviter laxe pilosae. Nectarium unicum adaxiale lineare 0.8--1.2 mm longum. Capsulae (sub) sessiles, maturae 2.5--3.5 mm. longae, breviter ovatae ab ima basi dense adpresse pilosae. Styli 1.0--1.2 mm longi, ad 1/3 (vel ima basi tantum) connati, dein divergentes, purpurascentes; stigmata parvula (0.1--0.2 mm), subintegra v. indistincte biloba.
Habitatio: in subalpinis jugi montium Diancang Shan videtur endemica.
Species affines: Orientali-Himalaicae S. eriostachya Anderss. et S. thomsoniana Anderss.; Orientali Tibetica S. zayulica C. Wang et C. F. Fan; Yunnanica S. resecta Diels. A S. bouffordii differunt: S. eriostachya - foliis ellipticis (latitudine maxima ad medium laminae) apice acuto, planis, subtus nervis lateralibus haud prominentibus pubescentia conspicue argentea destitutis, nectario ovato, quadrato v. fere cordato 0.5--0.8 mm longo, stigmatibus distinctius bilobis; S. thomsoniana et S. zayulica - habitu prostrato, trunco repent radicante, amentis vulgo pedunculo proprio brevioribus, capsulis (imabasi saltem), glabrescentibus; S. resecta - statura altiore, foliis adultis subtus glaucis glabris, capsulis majoribus (3.0--4.5 mm longis) apice acutioribus, maturis plus minusve glabrescentibus, stylis ad 1/2--2/3 connatis.
Paratypus: Yunnan, Dali Xian, Diancang Shan, prope praedium herbarum medicinalium Huadianba, alt. 3100 mm, 19 Jul 1984, Expeditio Botanica Sino-Americana 1151 (A, KUN).
Hanc speciem nomine indagatoris florae Chinensis diligentissimi Universitatis Harvardianae sodalis cl. Davidi E. Bouffordii ornamus.
Contrary to sect. Myrtosalix, sect. Eriostachyae, established by Schneider (1916), as yet remains a rather confused entity. Salix eriostachya Anderss. seems not to be represented in China, and sect. Eriostachyae is not mentioned in Flora Reipublicae Popularis Sinicae (Vols. 20--24, 1984). The Chinese species referred by Schneider to this section, in Flora Reipublicae Popularis Sinicae, are placed with sect. Psilostigmatae Schneid. I believe sect. Eriostachyae may be retained, but its circumscription should be considerably changed. Besides Salix eriostachya and S. bouffordii, to the section should be referred S. thomsoniana, S. zayulica, and S. resecta (the latter in FRPS is referred to sect. Eriocladae Hao), as well as S. annulifera Marq. & Airy-Shaw and S. floccosa Burkill. The latter is the type of sect. Floccosae Hao. Thus, sect. Floccosae Hao becomes a synonym of sect. Eriostachyae Schneid. Still more species may be referred after further consideration. Specimens of Salix bouffordii at KUN have been preserved under the name S. resecta Diels.
Acknowledgments: I express my deep gratitude to the Flora of China Project and to Dr. Peter H. Raven for the support that enabled me to continue my studies of eastern Asian willows, as well as to colleagues at the Harvard University Herbaria and the Beijing and Kunming Institutes of Botany Herbaria for their hospitality and manifold assistance.
Literature Cited
Schneider C. K. 1916. Salicaceae, Salix. Pages 40--179 in C. S. Sargent, ed., Pl. Wilson. Vol. 3. University Press, Cambridge, Massachusetts.
