NOVON 9(1): 79-82. 1999.

A New Species of Larix (Pinaceae) from Southeast Tibet and Other Nomenclatural Notes on Chinese Larix

Robert R. Mill

Royal Botanic Garden, 20A Inverleith Row, Edinburgh, EH3 5LR, Scotland, United Kingdom

Abstract. Larix kongboensis, a new species from southeastern Xizang (China) near its borders with Arunachal Pradesh (India), is described. Previously misidentified as L. mastersiana, its affinities with that Sichuan endemic and with L. griffithii (eastern Himalaya) and L. speciosa (Yunnan, Myanmar) are discussed. Within L. potaninii Batalin, variety australis A. Henry ex Handel-Mazzetti has been found to be an earlier name for variety macrocarpa Y. W. Law. The nomenclature of the "Sikkim Larch" is discussed, and it is concluded that Larix griffithii J. D. Hooker, not L. griffithiana Carrière, is the correct name for this species.

In the course of revising the genus Larix for the Flora of China, it was discovered that three specimens from southeastern Xizang named by their original collector as L. mastersiana were not that species. Because they do not match any other species in the group with exserted, reflexed bract scales, they are described below as L. kongboensis.

Larix kongboensis R. R. Mill, sp. nov. TYPE: China. Xizang: Tamnyen La, 29°18¢N, 94°45¢E, alt. 11,000 ft. [3353 m], 21 July 1938, F. Ludlow, G. Sherriff & G. Taylor 4914 (holotype, E; isotype, BM; female cones and mature leaves of current year).

Affinis L. griffithii J. D. Hooker bracteorum apicibus sursum curvatis sed foliis multo minoribus, aestate tantum 9--22 mm (non 30--55 mm) fasciculis densioribus foliorum 40--50 (non 28--36), brachyblastis fertilibus foliatis, strobilis masculis multo brevioribus (6--8 mm, non 10--16 mm) rubescentibus (haud flavescentibus), strobilis femineis maturis 2-plo (non 2.5--3-plo) longioribus quam latioribus differt. A Larice mastersiana Rehder & Wilson apicibus brachyblastorum glabris (non densiuscule flavidopilosis), brachyblastis brevioribus et angustioribus, epidermide foliorum epapillosa, foliis in fasciculis magis numerosis (40--50, non 25--40), et apicibus bracteorum sursum curvatis recedit.

Trees, 9--25 m tall. Bark and branching habit unknown. Long shoots of first year not seen, of second year pale reddish brown, glabrous, of subsequent years pale gray. Short shoots 2--4.5 ´ 4.5--6 mm, broadly obconical; leaf cushions glabrous. Leaves in fascicles of 40--50, linear-oblong, straight or slightly falcate, 6--12 mm in spring, finally 9--22 ´ 0.6--1.1 mm; midrib raised adaxially only proximally; stomatal lines 3--5 on each side of midrib abaxially, none adaxially; epidermis not papillose. Cone-bearing short shoots with leaves; cones short pedunculate (peduncle not more than 4 mm). Pollen cones erecto-patent at 45°, reddish, broadly conical, 6--8 ´ 5.5--6.5 mm. Seed cones at flowering stage not seen. Cone deflexed outward from main shoot axis, gray-brown when ripe, oblong-ellipsoid, 4.5--5 ´ 2.2--2.5 cm; seed scales broadly obovate-reniform, median ones ca. 8 ´ 10 mm, apex broadly rounded, entire or shallowly retuse, abaxial surface minutely whitish pubescent; bract scales exserted, lanceolate, exposed part ca. 8 ´ 5.5 mm, strongly reflexed, tapered gradually then finally more abruptly into a cusp; cusp 1.5--4 mm, turned upward at tip. Seeds not seen. Flowering April. Fruiting late summer--autumn.

The three specimens cited and described as the new species Larix kongboensis were all originally named as L. mastersiana Rehder & Wilson, and one of them is also mentioned under that name in a quotation from Ludlow and Sherriff’s journal (Fletcher, 1975: 88), where the trees concerned are described as "a very fine larch." The area of southeastern Tibet (Xizang, China) in which the specimens were collected lies in Kongbo, from which the epithet is derived. This area, close to the border with Arunachal Pradesh (northeastern India), has yielded numerous new endemic species, primarily as a result of the collecting expeditions by Ludlow et al. and by F. Kingdon-Ward.

Larix mastersiana Rehder & Wilson is an endangered species, endemic to a small area of western Sichuan. It differs from L. kongboensis in several characters, notably the pale yellowish-pilose leaf "cushions," longer and relatively narrower short shoots, fewer (25--40) leaves per fascicle which have a papillose epidermis, and the bract scales whose apical cusp is not turned upward at the tip.

Larix kongboensis is closer to L. griffithii in its characters and distribution, and the latter occurs in Bhutan, Nepal, and Sikkim, and has been recorded from Xizang (Law et al., 1978: 171--173). It is possible that at least some of the Xizang records of L. griffithii actually belong to L. kongboensis. Larix griffithii differs by its fewer, much longer leaves (3--5.5 cm), its usually leafless cone-bearing short shoots, much larger, yellowish pollen cones, and seed cones twice as long and 2.5--3´ as long as broad (not 2´ as long as broad). Characters L. kongboensis shares with L. griffithii but not L. mastersiana include the upturned apex of the bract scales, the non-papillose leaf epidermis, and the glabrous leaf cushions.

The only other Chinese larch with reflexed bract scales is Larix speciosa W. C. Cheng & Y. W. Law. Specimens of this have been seen from Yunnan as well as northern Myanmar; again, it has been recorded from Xizang but verification is necessary. It is easily separable from L. kongboensis by its stout, often very long short shoots (up to 3 cm), longer leaves (2.5--5.5 cm), pollen cones much larger (1.6--2.2 cm), chocolate-colored mature cones, and bract scales whose apical cusp is not turned upward at the tip.

Paratypes. CHINA. Southeastern Xizang: Lunang, Rong Chu, Kongbo, 29°44¢N, 94°48¢E, 10,500 ft. [3200 m], fairly common at the upper limit of spruce and pine, 12 Apr. 1947, F. Ludlow, G. Sherriff & G. Taylor 12376 (BM, E; male cones and old female cone of previous year); Natrampa-Lung, Chayul Chu, 11,500 ft. [3505 m], tree 30--80 ft., rocky slopes and rhododendron and bamboo jungle, transition zone, 27 Apr. 1936, F. Ludlow & G. Sherriff 1367 (E, BM; spring leaves).

Larix potaninii Batalin var. australis A. Henry ex Handel-Mazzetti, Symb. Sin. 7(1): 14. 1929. TYPE: China. NW Yunnan: "prope fines Tibeto-Birmanicas inter fluvios Lu-djiang (Salween) et jiou-diang (Irrawadi or. sup.), in jugi Tschiangschel, 27°52¢[N], lateris utriusque regione temperata in silvis mixtis, substr. micoschistaceo," 2850--3500 m, 2 & 5 July 1916, H. F. von Handel-Mazzetti 9176 (Diar. Nr. 1754,[17]70) (holotype, W not seen; isotype, E).

Larix potaninii Batalin var. macrocarpa Y. W. Law, in W. C. Cheng, L. K. Fu & C. Y. Cheng, Acta Phytotax. Sin. 13(4): 84. 1975. Syn. nov. TYPE: China. Central Yunnan: 2800--3600 m, Feng Guomei 9347 (holotype, PE not seen).

Augustin Henry’s neglected varietal epithet appears as a very brief note in Handel-Mazzetti’s account of Larix (Handel-Mazzetti, 1929), but as the minuscule description mentions that the cones are 7 cm long, it is sufficient to equate the name with Y. W. Law’s variety macrocarpa based on material from Muli, southwestern Sichuan. The Edinburgh isotype (Handel-Mazzetti 9176) consists of two packets mounted on a herbarium sheet, one containing only leaves and bearing a label "Larix Potaninii Bat. var. nova australis Henry det. A. Henry," the other containing only cones and unlabeled, but with a loose ticket within labeled "ad No. 9176 Larix Potaninii var. australis." Three of the four cones measure 4.8--5.5 cm; the fourth is slightly incomplete. They are thus at the minimum of the range allowed for variety macrocarpa by Y. W. Law, and at the maximum found in variety potaninii. They are also smaller than variety australis as described by Handel-Mazzetti.

Larix griffithii J. D. Hooker, Himal. Journal 1: 255--256 (as "Saar," without Latin name), 2: 44 & 481 (Jan. 1854). SYNTYPES: [Nepal] Nango Mt., J. D. Hooker (K); [Sikkim] Lachen, J. D. Hooker & Thomson (K).

Abies griffithiana J. D. Hooker ex Lindley & Gordon, J. Roy. Hort. Soc. London 5: 214. 1850, nom. subnud. No type designated.

Larix griffithiana hort. ex Carrière, Traité Gen. Conif. 278. Jun. 1855.

The name of the Sikkim larch has vacillated between Larix griffithiana and L. griffithii almost since the species was first named, due in part to the two epithets appearing within one month of each other. There is disagreement even in the most recent treatments: Grierson and Long (1983) used L. griffithiana Carrière, Farjon (1990) L. griffithiana (Lindley & Gordon) Carrière, and Silba (1986) L. griffithii Hook. f. A similar confusion exists when several popular books on trees are compared.

Carrière’s epithet griffithiana originally appeared as Abies griffithiana J. D. Hooker ex Lindley & Gordon (1850). However, Lindley and Gordon’s description merely reads "A tree 40 to 60 feet high (The Sikkim Larch)"; the distribution, "Eastern Nepal, Sikkim," is also given. This description contains no characters that diagnose this larch against any other species of Larix, or indeed against any other tree. It is not considered enough to validate Lindley and Gordon’s name, and the epithet griffithiana should be considered to date from Carrière’s first adequate description, published in June 1855.

Hooker’s epithet griffithii is generally considered to date from July 1855, when it appeared in Hooker’s Illustrations of Himalayan Plants (Hooker, 1855) as Larix griffithii J. D. Hooker & Thomson; Hooker himself (1888) cited this reference as the place of publication, with L. griffithiana Gordon, Abies griffithiana Lindley & Gordon, and Pinus griffithii Parlatore listed as the only synonyms. It would thus be antedated, by one month, by L. griffithiana Carrière, of whose publication Hooker (and also Bean, 1908) seems to have been unaware; hence the preponderance of use of griffithiana in most, but not all, recent literature, including Flora Reipublicae Popularis Sinicae.

However, Hooker also published the name in his Himalayan Journals (Hooker, 1854), both volumes of which were published in January 1854, 18 months before Larix griffithiana Carrière. In volume 1, pp. 255--256, there is a detailed description of a larch, with two vernacular names, but no Latin epithet. Hooker had discovered the tree at Nango Mountain, eastern Nepal (Bean, 1908). The description reads as follows: "December 5 [1848].--...We descended at first through rhododendron and juniper, then through black silver-fir (Abies Webbiana), and below that, near the river, we came to the Himalayan larch; a tree quite unknown, except from a notice in the journals of Mr. Griffith, who found it in Bhotan. It is a small tree, twenty to forty feet high, perfectly similar in general characters to a European larch, but with larger cones, which are erect upon the very long, pensile, whip-like branches; its leaves,--now red--were falling, and covering the rocky ground on which it grew, scattered amongst other trees. It is called ‘Saar’ by the Lepchas and Cis-Himalayan Tibetans, and ‘Boarga-sella’ by the Nepalese, who say it is found as far west as the Cosi river; it does not inhabit Central or West Nepal, nor the North-West Himalaya."

The first actual mention of the name Larix griffithii is in volume 2, p. 44, which is the usual citation found in the literature, generally qualified by the statement "nomen" or "nom. nud." (e.g., Bean, 1908). Hooker was here describing the conifers of a steep hill in the Lachen valley, near a point where the river divides, and where some stacks of different conifer woods were stored for export to Tibet. Discussing this wood pile, Hooker wrote, "Of these the larch (Larix Griffithii, ‘Sah’) splits well, and is the most durable of any; but the planks are small, soft and white."

The vernacular name "Sah" is presumably a different rendering of "Saar" used in volume 1, p. 255, and could be used to argue that he was referring in both places to the same taxon. However, what is more significant is that it is clear from the index to the whole work that the plant supplied with a full description but no Latin name in the first volume belongs to the same species as the one given a name but only a description of its sawn plants in the second. The index entries on p. 481 of volume 2 read:

Larch, Himalayan, i. 255; sketch of, ii. 55.

Larix Griffithii, i. 255; ii. 44.

From these it is obvious that Hooker knew that his description of "Saar" in the first volume was of Larix griffithii, which should thus not be considered a nomen nudum in this publication but validated by an indirect reference (Art. 32.5 of ICBN, Greuter et al., 1994), via the index, to the description in volume 1. Since the two volumes were simultaneously published, the name can be taken to date from January 1854. Larix griffithii Hooker is thus the correct name for the Sikkim Larch. "Sikkim Larch" (as used by Mitchell, 1974) is a better English name for this species than "Himalayan Larch," which is sometimes used (as for example by Hooker), because of the existence of another Himalayan larch, L. himalaica W. C. Cheng & L. K. Fu.

As Hooker (1854) mentioned incidentally, Larix griffithii was in fact first discovered by William Griffith, on 10 May 1838, in Bhutan, "above Woolookha, 9,600 ft." Griffith (1848: 189, no. 1010) gave a short Latin description: "Arbor parva, ramulis elongatis pendulis, foliis plurimis complanatis, conis ascendentibus, squamis rubro fuscis, longe apiculatis, apiculo viridi deflexo." However, his entry is merely labeled "Larix sp." The supporting specimen is at K.

Acknowledgments. The Royal Botanic Garden, Edinburgh, is supported by The Scottish Office Agriculture, Environment and Fisheries Department.

Literature Cited

Bean, W. J. 1908. Larix Griffithii. Bot. Mag. 134: t. 8181.

Farjon, A. 1990. Pinaceae. Drawings and Descriptions of the Genera Abies, Cedrus, Pseudolarix, Keteleeria, Nothotsuga, Tsuga, Cathaya, Pseudotsuga, Larix and Picea. Regnum Veg. 121.

Fletcher, H. 1975. A Quest of Flowers. Edinburgh Univ. Press, Edinburgh.

Greuter, W., F. R. Barrie, H. M. Burdet, W. G. Chaloner, V. Demoulin, D. L. Hawksworth, P. M. Jørgensen, D. H. Nicolson, P. C. Silva, P. Trehane & J. McNeill. 1994. International Code of Botanical Nomenclature (Tokyo Code). Regnum Veg. 131.

Grierson, A. J. C. & D. G. Long. 1983. Flora of Bhutan, Vol. 1. Royal Botanic Garden, Edinburgh.

Griffith, W. 1848. Posthumous Papers Bequeathed to the Honourable, the East India Company, and Printed by Order of the Government of Bengal. Vol. II. Itinerary Notes of Plants Collected in the Khasyah and Bootan Mountains, 1837--38, in Affghanistan and Neighbouring Countries, 1839 to 1841. By the late William Griffith, Esq., F.L.S. Arranged by John McClelland, F.L.S. Bishop’s College Press, Calcutta.

Handel-Mazzetti, H. F. von. 1929. Symbolae Sinicae Botanische Ergebnisse der Expedition der Akademie der Wissenschaften in Wien nach Südwest-China. 1914/1918. Part 7(1). Julius Springer, Wien.

Hooker, J. D. 1854. Himalayan Journals; or, Notes of a Naturalist in Bengal, the Sikkim and Nepal Himalayas, the Khasia Mountains, &c. John Murray, London.

---. 1855. Illustrations of Himalayan Plants chiefly selected from drawings made for J. F. Cathcart Esq. of the Bengal Civil Service. Privately published, London. [Frequently attributed, wrongly, to Cathcart in the literature.]

---. 1888. Coniferae. In: J. D. Hooker, Flora of British India 5: 643--655.

Law, Y.-W., W.-C. Cheng & L. K. Fu. 1978. Larix. In: Cheng W.-C. & L.-K. Fu (editors), Fl. Reipubl. Popularis Sin. 7: 168--196.

Lindley, J. & G. Gordon. 1850. A catalogue of coniferous plants, with their synonyms. J. Hort. Soc. London 5: 193--228.

Mitchell, A. 1974. A Field Guide to the Trees of Britain and Northern Europe. Collins, London.

Silba, J. 1986. Encyclopaedia Coniferae. Phytologia Memoirs VIII. Corvallis, Oregon.