Volume 13 NOVON Number 3 2003 A New Hard Pine (Pinus, Pinaceae) from Taiwan Roman Businsky Silva Tarouca Research Institute for Landscape and Ornamental Gardening (RILOG), 252 43 PruÊhonice, Czech Republic. [email protected] ABSTRACT. Pinus fragilissima Businsky (Pina- TAXONOMY ceae), a new species of Pinus subg. Pinus, is de- During an exploration in 1991 of forest stands in scribed from southeastern Taiwan. Comprised of southern Taiwan, on the eastern (Paci®c) side of the trees with very sparse crown and fragile, symmet- island's central mountain range, a remarkable pop- rical, 6±9 cm long cones with often ¯at apophyses, ulation of a hard pine (5 Pinus subg. Pinus) near it appears to be most closely related to P. luchuensis Wulu village in the northern part of Taitung County Mayr, endemic to the Nansei Islands, and to P. tai- was found. The only species known from Taiwan wanensis Hayata. The latter is circumscribed here showing certain resemblance in general tree habit, as a Taiwan endemic with the exclusion of super- external leaf characters, and some cone characters ®cially similar but probably unrelated mainland to this population is Pinus massoniana Lambert. Chinese pines. These three allied species are clas- Critch®eld and Little (1966), using unpublished si®ed here as the sole representatives of Pinus data at the Taiwan Forest Research Institute, re- subg. Pinus ser. Luchuenses E. Murray. ported P. massoniana only from northern Taiwan. Key words: Pinaceae, Pinus, Pinus subg. Pinus However, Liu (1966) and Li (1975) also reported P. ser. Luchuenses, Taiwan. massoniana in the south, but only from the eastern coastal hills along the border between Taitung and Hualien Counties. Liu (1966: ®g. 33) listed only The author has been studying natural popula- one species of hard pine, P. taiwanensis Hayata, in tions of Eurasian pines for more than ten years, the Wulu region. In a narrow taxonomic concept concentrating on East Asia. The main object of the (excluding Pinus hwangshanensis W. Y. Hsia, see study is a taxonomic revision of Pinus in that re- below), P. taiwanensis is con®ned to middle and gion, the Revision of Pines of East Asia (REPEA) high altitudes of Taiwan, widespread mainly be- Project. Within the framework of this project, the tween 2200 and 2900 m. However, the pine from author undertook a series of research expeditions the vicinity of Wulu occurs near or below 900 m, to East Asia: eight to the People's Republic of Chi- and differs from P. taiwanensis in several morpho- na (1990±2001), two to Japan (1991 and 1997), two logical characters (Table 1). No other indigenous to Vietnam (1994 and 1997), and one to Taiwan hard pine is known from Taiwan. Outside of Taiwan, (1991), Indonesia (1994), and the Philippines the Wulu population approaches P. luchuensis Mayr (2000). The study has been designed to obtain good in some characters (leaf morphology and anatomy, ®eld knowledge, above all of variability within and distinctly broad tree crown); this is a species en- between populations, and to collect representative demic to the nearby ¯at islands of the Nansei (Ryu- herbarium and photographic material of all Asian kyu) Archipelago, northeast of Taiwan (cf. Critch- species of the genus Pinus, allowing a more uniform ®eld & Little, 1966; Yamazaki, 1995). The approach to classi®cation (see also BusinskyÂ, character set found in the Wulu pine is different 1999). from that of the three geographically closest spe- NOVON 13: 281±288. 2003. 282 Novon cies: P. massoniana, P. taiwanensis, and P. luchuen- to)45 to 65(to 80) teeth per cm in the middle part; sis. The Wulu pine also cannot be equated with any sheaths (8±)10±13(±15) mm long in the ®rst year. other pine indigenous to East Asia, either; so as Leaf resin ducts 4 to 6(7); two ducts near leaf edges discussed below it is described here as a new spe- always median, of largest diameter; 1 to 3(4) ducts cies. dorsal, usually of smaller diameter, median or 1 to 2 of them marginal, occasionally submarginal, or Pinus fragilissima BusinskyÂ, sp. nov. TYPE: Tai- near endodermis; usually one duct near the ventral wan. Taitung County: below the great bend of side of small diameter, median to marginal (rarely Southern Cross-Island Highway on S slopes larger and septal). Leaf hypodermis formed mostly about 1 km N of Wulu village, in mixed forest by one layer of cells with relatively thin walls, on W declivity of a stony ridge descending S, sometimes a second layer in scattered patches on alt. 930 m, 238109400N, 1218029E, 18 Dec. the dorsal side. Pollen cones ca. 2.5 cm long. Ovu- 1991, R. Businsky 32172 (holotype, PR; iso- late cones after the ®rst growing season (conelets) types, B, BM, C, G, MO, P, PE, TAI & Her- on 5±10 mm long peduncles, 13±18(±20) mm long barium of the RILOG). Figure 1. and ca. 9±10 mm wide, ovoid to elliptic cylindrical, erect, subterminal, usually in whorls of 3 to 5. The Arbor usque 30 m alta, corona conspicue sparse dif- fusa, lata; folia (12±)16±20(±22) cm longa, canalibus re- exposed part of the scales of the basal quarter of siniferis 4 ad 6(7), plerumque medialibus et interdum the conelet rounded, without a distinct keel or mu- (sub)marginalibus; strobili ovuliferi hornotini fere 9±10 cro; the other scales often show a considerably el- mm lati, pedunculis 5±10 mm longis, squamis mucronatis evated area with a distinct transverse keel without praeter partem strobilorum basalem; strobili maturi (5±)6± 9(±10) cm longi, fragiles, patentes vel leviter re¯exi; discernible apex, dorsally depressed, with short apophyses plerumque prominentes, non tumidae. A Pinus mucro situated eccentrically on the ventral side, massoniana differt imprimis canalibus resiniferis foliorum beginning from the swollen decurrent base and ori- plerumque medialibus et umbonibus strobilorum maturo- ented backward over the keel. Mature seed cones rum plerumque prominentibus, non planis et concavis; a spreading or slightly re¯exed on slender 5±10 mm P. taiwanensi differt imprimis foliis longioribus, strobilis maturis longioribus, fragilibus et coronis arborum sparse long peduncles, symmetrical, ovoid to oblong con- diffusis; a P. luchuensi differt imprimis strobilis maturis ical, fragile, (5±)6±9(±10) cm long, 5±8 cm wide longioribus et fragilibus, non suberectis, apophysibus when open; usually persistent for a few years, fall- plerumque pyramidalibus, non rotundatis vel tumidis et ing mostly without peduncle. Cone scales thin, coronis arborum sparse diffusis. densely arranged, 120 to 220, the largest 20±30 Tall trees attaining a height of 30 m with con- mm long and 12±15 mm wide, with length/width spicuously sparse crowns 20 m or more wide, ratio 1.5±2.5, often broader below the middle than branches spreading, remarkably frangible, with the apophysis width. Apophyses cinnamon brown, in leaves falling during the second to third year. Bark outline irregularly transverse obtrullate, 11±14 mm developing late, initially irregularly scaly, on trunks wide, with rounded to broadly cuneate distal edge, of old trees conspicuously thick, deeply longitudi- 6 broadly pyramidal (not rounded or tumid), with nally ®ssured and forming ribs often around 10 cm conspicuous, sharp transverse keel and generally thick. Annual branches uninodal, relatively long; concave, depressed proximal side (often with raised shoots of the current year relatively thin (fertile proximal corner). Umbo slightly sunken, but usu- shoots with conelets 3±6 mm thick), yellow-brown, ally prominent, transverse, (2±)2.5±4(±4.5) mm initially slightly pruinose, glossy, with inconspicu- wide on seed scales, pyramidal or roo¯ike, keeled, ous shallow and narrow grooves formed by the de- often depressed on the proximal side, with minute, current bases of the primary bracts; areolae among slender, ca. 0.2±0.5 mm long, erect or recurved them low and relatively ¯at. Shoots of the previous mucro. Seeds ca. 4±5.5 3 2.2±3 mm, with wings year gray-brown. Buds cylindrical, up to ca. 3 cm 11±25 3 4.5±7.5 mm. long, with scales in the upper half loose to erecto- Etymology. The speci®c epithet (denoting ``fra- patent, narrowly lanceolate, with inconspicuous gilest'') refers to the remarkably frangible branches dorsal keel, brown in the middle, paler toward the and branchlets, more so than for all other East lacerate margins, with long white fringes; scales not Asian pines, and to the fragile consistency of the persistent at the bases of shoots. Leaves in fascicles scales of mature seed cones. of 2, occasionally in 3s on fertile shoots, (12±)16± 20(±22) cm long, (0.9±)1.0±1.2(±1.35) mm wide DISTRIBUTION AND ECOLOGY (fresh), pale green, relatively ®ne and ¯exible, straight or slightly bent; amphistomatic; edges ir- Pinus fragilissima was observed only in a rela- regularly and rather densely acute-serrate, with (35 tively small valley system of the Hsinwulu River, Volume 13, Number 3 Businsky 283 2003 Pinus fragilissima from Taiwan Figure 1. Pinus fragilissima BusinskyÂ. ÐA. Fertile branchlet in winter season (current shoot, with top of previous year's shoot) with leaf fascicles, terminal bud and ovulate cones. ÐB. Mature closed cone. ÐC. Open seed cone. ÐD. Cross sections at the middle of leaves showing position of resin ducts. ÐE. Open seed cone of another individual. A±D from R. Businsky 32172, holo- and isotypes, and E from R. Businsky 32173, paratype. A, B, C, E: the same scale bar. All drawn by Ludmila BusinskaÂ. 284 Novon Table 1. Comparison of Pinus fragilissima with three morphologically most similar species: P. taiwanensis, P. luchuensis, and P. massoniana (compiled from the author's ®eld collections of natural populations, see Appendix 1).