Quercus glauca Thunb.

DENG, Min, LI, Qiansheng, COOMBES, Allen & XU, Jin, 2013, Typification of Quercus acuta Thunb. and Q. glauca Thunb. (Fagaceae), Phytotaxa 137 (1), pp. 27-34 : 31-33

Quercus glauca Thunb. in Murray, Syst. Veg. ed. 14: 858. (1784)

Lectotype (designated here):— JAPAN. “e Japonia”, Thunberg C.P. s.n. [UPS-Thunb 22412] (UPS!, Fig. 4). ≡ Cyclobalanopsis glauca (Thunb.) Oerst .., Vidensk. Meddel. Dansk Naturhist. Foren. Kjøbenhavn 1866: 78 (1866).

Additional specimens cited:

JAPAN. Nagasaki: Maximowicz. Iter secundum s.n. 1863 (K!); Yonekura, K. 96273 [IBSC0074607] ( IBSC!) , Thunberg , C.P. [UPS-Thunb. 22413] ( UPS!) ; Wakayama: Oze Kita-yama-son Higashi-muro-gun, Furuse M. 48462 (K!); Kyushu: Kagoshima Pref. Kimotsuki-gun , Gohei-machi , 11 Oct. 1981, Murata, J. 11873 ( PE!) ; Honshu: Shizuoka pref., Thara-gun, Fujigawa-machi , along the Arinase Riv. alt. 150-350m, 21 Oct. 1978, Tateishi, Y., Murata, J. Akiyama, S. & Midorikawa, K. 4498 (IBSC!, PE!); Without detail locality: Thunberg, C.P. s.n. [LINN-HS 1478.4: http://linnean-online.org/47989/#] (LINN![scan seen]) . CHINA. Anhui: Wu-yi-shan, Dapai , close to the stream, Mao, Z.G. 10654 [PE00310238] ( PE!) ; Guangdong: Lokchong , 10 Oct. 1928, Tsiang, Y. 1334 [P06859365] (P!); Zhaoqing, Qi-Xing-Yang, Yu-Yuang-Feng, alt. 750m, Deng, M. 3747 ( CHS!) ; Guangxi: Longjin, Wu-lian, Ban-Bi village, Sha-Kao shan, alt. 450-600 m, Chen, S.Q. 13449 [IBSC0039555] ( IBSC!) ; Hongkong, Feng-Huang-Shan, Chen , N.Q. 41896 ( IBK!) ;

Jiangsu: I-hsing, Kiangqu, Shen, T. 944 [SYS00031527] ( SYS!) ; Zhejiang: Longquan , Feng-Yang-Shan, NW slope, in the ravine, close to stream, alt. 1600 m, 31 July 1958, Zhang, S.R. 3179 ( KUN!) ; Jiangxi: Lushan , Guang-yin-qiao, close to the ravine, 10 Oct. 1957, Sheng, L.J. 00815 [IBSC0040644] ( IBSC!) ; Qiangshan, Wu-yi-shan, Dong-Keng , 18 Aug. 1958, Lai, S.K. & Nie, M.X. 4281 [IBSC0040645] ( IBSC!) ; Hunan: Dong- an, Shun-huang-shan, Zhi-Hua-Pin, 1 Nov. 2004, alt. 620 m, Liu, J.K. 836 [P05591909] (P![scan seen]) ;

Guizhou: Rongjiang, Yue-liang-shan, in the ravine, S. Guizhou Exped. 3289 ( SZ!) ; Sichuan: Feng-Zhu- Yuan, Xing-zheng Village, by the river, alt. 520m, 13 July , 1964. Zhou, H.F. & Zhang, H.Y. 108981 ( SZ!) ;

Taiwan: Central mountain area, 10 Dec , 1932, Tanaka, T. 13470 [IBSC0043845] ( IBSC!) ; Mt. Bosisan, Taihoku, 21 Jun. 1931, Suzuki s. & Saito, G. 7685 [IBSC0043847] ( IBSC!) ; Taoyuan, Kaoi bridge, 11km NW of Paling on Hwy 7, at Km 39-40, in secondary broadleaf evergreen forest on slopes along road, 24º44'N, 121º20'E, elev. 525, 24 Sept. 1991, Lammers, T.G. 8509 [IBSC0034644] ( IBSC!) .

Habitat: Monsoon broad-leaf evergreen forest.

Distribution: This species is widely distributed in subtropical regions of E and SE Asia.

Leaf epidermal features: The plant materials used for leaf epidermal studies represented typical Q. glauca from Japan. The leaf abaxial surface was covered by platelet wax flake ( Fig. 5 C ). The ALA trichomes ( Figs. 5C & D ) were generally present on the abaxial leaf surface and the hair colour is from white to grayyellow. U trichome was also found, but rare. The epidermal cells were flat, and irregular to polygonal in shape. The stomata were non-typical cyclocytic type. The stomatal size (L × W) is 25.0 ± 0.9 × 20.2 ± 0.5 µm with the stomatal frequency 641.8 ± 7.2/mm 2 .

Observations: The taxonomy of Q. glauca and closely related species ( Q. myrisinifolia Blume , Q. schottkyana Rehder & E.H. Wilson , Q. ciliaris C.C. Huang & Y.T. Chang , Q. hypargyrea (Seemen) C. C. Huang & Y. T. Chang. , Q. oxyodon Miquel. , Q. stewardiana A. Camus ) is confusing because of the sympatric distribution pattern of those species, and continuous morphological variations among the different populations ( Deng 2007). Q. glauca can be distinguished from related species by the prominent secondary leaf veins, the smooth, straight ALA trichomes, the almost glabrous acorn cupule wal1, the one-year acorn maturation and smooth epidermal cells of the abaxial leaf surface. Future studies to compare the morphological variations of different populations of Q. glauca and its relatives are needed to clarify the taxonomic confusion of this group.

Figures

FIGURE 5. Leaf epidermal features of typical Q. acuta and Q. glauca observed under SEM and LM. bar=50 µm. A-B. Q. acuta, black arrows show ALA, white arrows show U; C-D. Q. glauca, showing the platelet wax flake and ALA on leaf abaxial epidermis.