Abies ziyuanensis

L.K. Fu et S.L. Mo 1980

Common names

Zhiyuan fir; Zhiyuan lengshan [Chinese] (Farjon 1990).

Taxonomic notes

Syn.: Abies beshanzuensis var. ziyuanensis (L.K. Fu & S.L. Mo) L.K. Fu & Nan Li; A. dayuanensis Q.X. Liu; and A. fabri var. ziyuanensis (L.K. Fu & S.L. Mo) Silba) (Fu et al. 1999).

Description

Trees to 30 m tall and 90 cm dbh, with a straight round trunk and long, horizontally spreading branches. Bark smooth and gray on young trees, becoming pale gray, irregularly scaly, ridged and grooved. Branchlets stout, initially light yellow or brown-yellow, sometimes turning gray-black in 3rd or 4th year, surface ridged and grooved, glabrous or with short hairs in grooves, with circular leaf scars. Vegetative buds ovoid to conical, covered with a coat of white resin resin, the scales triangular, light yellow-brown. Leaves spirally arranged, ascending on upper side of main branchlets, pectinately arranged in 2 lateral sets on lower side and on lateral branchlets, linear, unequal, (1-)1.5-3.5(-4.2) cm × 2.5-3.5 mm, stomata lines in 2 white bands on the lower surface, resin canals 2, marginal, apex emarginate. Pollen cones lateral, in leaf axils, ca. 2 cm long, yellow with red microsporophylls. Seed cones lateral, borne on 5-10 mm long peduncles, green or yellow-green, later dark green-brown, later dark brown at maturity, cylindric-ellipsoid, 7-12 × 3.5- 4.5 cm, rachides persistent. Seed scales at middle of cones flabellate-trapeziform, rarely reniform-trapeziform, 2.3-2.5 × 3-3.3 cm, base auriculate, margin erose-denticulate laterally. Bract scales 21-23 mm long, constricted at middle, distal part spatulate, orbicular, or truncate, apex cuspidate, cusp exserted, reflexed, acute, small. Seeds purple-gray, obtriangular, ca. 10 mm long, 20-24 mm including spotted, shiny, broadly dolabriform wing. Winter buds conical. Pollination May, seed maturity Oct-Nov (Farjon 1990, Fu et al. 1999).

Compared to Abies beshanzuensis M.H. Wu, it has oblong terminal buds, oblong-cylindric (not conical) female cones that are a dark greenish-brown to dark brown when ripe, wider or larger seed scales (especially the exposed abaxial sides), wider apical part of the bract scales (almost round-truncate), and purplish seed wings (Farjon 1990).

Distribution and Ecology

China: I have found two sources for this information and they differ significantly. The more recent assessement, by Fu et al. (1999), places it in hill country at 1400-1800 m elevation in NE Guangxi (Ziyuan Xian), S Hunan (Chengbu Miaozu Zizhixian, Ling Xian, Xinning Xian), and W Jiangxi (Jinggang Shan). An older description, by Farjon (1990), places it in NE Guanxi (Yuanbao Shan, 2081 m, and neighbouring mountains) and SW Hunan (type location: Yinzhulao Shan; between Tongdao, in Ziyuan Xian, and Chengbu, along the borderline between the two provinces). "It is thus confined to the highest mountains in Guangxi (2000-2100 m)."

Remarkable Specimens

No data as of 2022.12.31.

Ethnobotany

No data as of 2022.12.31.

Observations

No data as of 2022.12.31.

Remarks

Citations

Farjon, Aljos. 1990. Pinaceae: drawings and descriptions of the genera Abies, Cedrus, Pseudolarix, Keteleeria, Nothotsuga, Tsuga, Cathaya, Pseudotsuga, Larix and Picea. Königstein: Koeltz Scientific Books.

Fu Li-Kuo, L. Yong-Jun and Mo Sin-Li. 1980. The genus Abies discovered for the first time in Guangxi and Hunan. Acta Phytotaxonomica Sinica 18(2):205-210. Available online at the Journal of Systematics and Evolution.

See also

The species account at Threatened Conifers of the World.

Tang, Shaoqing; Dai, Wenjuan; Li, Mingshun; Zhang, Ying; Geng, Yupeng; Wang, Li; and Zhong, Yang. 2007. Genetic diversity of relictual and endangered plant Abies ziyuanensis (Pinaceae) revealed by AFLP and SSR markers. Genetica 2007.07.28 : 17661154. Abstract: Abies ziyuanensis is a highly endangered fir species endemic to South China. Unlike other Abies species that are distributed in areas with cold climates, A. ziyuanensis is restricted to several isolated island-like localities at subtropical mountains. In this study, we used dominant amplified fragment length polymorphism (AFLP) and co-dominant simple sequence repeats (SSR) markers to infer the genetic structure of A. ziyuanensis. Seven populations consisting of 139 individuals were sampled across their whole distribution. A. ziyuanenesis has a relatively low level of genetic variation, with a mean genetic diversity per population (H_e) of 0.136 (AFLP) and 0.337 (SSR), which is lower than that of other reported endemic species based on the same kind of marker. We observed high population differentiation, with G_st = 0.482 (AFLP) and F_st = 0.250 (SSR), among the seven populations. AMOVA also detected significant differentiation among populations (φ_st (AFLP) = 0.550 and φ_st (SSR) = 0.289) and among regions (φ_ct (AFLP) = 0.139 and φ_ct (SSR) = 0.135) in both marker types. Both ongoing evolutionary forces (e.g., genetic drift resulting from small population size) and historical events (e.g., population contraction and fragmentation during and after the Quaternary glacial cycles) may have contributed to the genetic structure in A. ziyuanensis.