Flora of China
  FOC Vol.13 (2007)              | Family List  Thymelaeaceae  PDF     | Link Font:+ Big | - Small
   17. Thymelaeaceae  A. L. Jussieu
瑞香科   rui xiang ke
Authors:Wang Yinzheng (王印政); Michael G. Gilbert, Brian Mathew, Christopher D. Brickell, Lorin I. Nevling


Shrubs or small trees, rarely herbs, evergreen or deciduous. Bark tough and fibrous. Leaves opposite or alternate, rarely some ternate, estipulate; blade simple, entire, pinnately veined, articulate at base. Plants mostly bisexual, sometimes dioecious. Inflorescences terminal or subterminal, less often axillary, sometimes on brachyblasts, sessile or pedunculate, basically racemose, sometimes capitate, spicate, umbelliform, or fascicled. Flowers usually actinomorphic, bisexual or unisexual (plants then mostly dioecious), bracteate (sometimes bracts forming an involucre) or ebracteate, sessile or pedicellate. Calyx tubular, campanulate, or infundibuliform, usually corollalike, 4- or 5(or 6)-merous, mostly caducous, sometimes circumscissile, or persistent; lobes imbricate. Petals absent or represented by 4-12 scales, inserted at or near throat of calyx tube (Aquilaria). Stamens 2 to many, usually as many as calyx lobes and opposite them or twice as many. Hypognous disk usually present at base of ovary, scalelike, annular or cup-shaped, sometimes absent. Ovary superior, 1- or 2-loculed, sessile or shortly stipitate; ovules solitary in each locule, pendulous, anatropous; style filiform, caducous, sometimes very short or obscure, terminal or eccentric; stigma capitate, globose, subglobose, subclavate, or pyramidal, sometimes papilose. Fruit mostly indehiscent, dry or fleshy, sometimes a loculicidal capsule (Aquilaria). Seeds with or without endosperm, embryo straight.

About 48 genera and ca. 650 species: widely distributed in both hemispheres; nine genera and 115 species (89 endemic) in China.

The phloem contains very strong fibers, which make the bark of many species very suitable for the manufacture of high-quality paper such as that used for bank notes. The stems are extremely supple and difficult to break and are used as a substitute for string. Most species are poisonous and some are important medicinally.

"Stellera formosana" (H. L. Li, Woody Fl. Taiwan, 619. 1963) and "Daphne formosana" (Halda, Genus Daphne, 83. 2001) were not validly published because they were based on "Chamaejasme formosana" (Hayata, Icon. Pl. Formosan. 6 [Gen. Ind. Fl. Formos.]: 64. 1917), which was itself not validly published because it lacked a description or diagnosis. The illustrations suggest that this plant is a species of Daphne. It was described as having a circumscissile calyx, which, if true, would exclude it from Daphne, and 4-merous flowers not enclosed in any bracts, which would place it in Diarthron. The specimens listed by Hayata proved to be Daphne arisanensis, but the material described and illustrated by Li and Halda is clearly not that species nor any of the other species recorded from Taiwan. This apparently distinctive endemic must remain effectively nameless until authentic material can be located to serve as a type and a validating description can be published in the appropriate genus.

Huang Shuchung & Zhang Zerong. 1999. Thymelaeaceae. In: Ku Tsuechih, ed., Fl. Reipubl. Popularis Sin. 52(1): 287-400.

1Calyx with petaloid appendages adnate to or inserted in throat; ovary 2-loculed; fruit a loculicidal capsule; trees.1  Aquilaria    沉香属
+Calyx without petaloid appendages; ovary 1-loculed; fruit an indehiscent berry, drupe, or nut; shrubs, subshrubs, or herbs, sometimes a small tree(2)
2(1)Calyx tube articulate above ovary, circumscissile in fruit(3)
+Calyx tube not articulate, persistent or caducous, not circumscissile(4)
3(2)Flowers 5- or 6-merous; inflorescence with involucre, terminal, capitate, not elongating in fruit.9  Stellera    狼毒属
+Flowers 4-merous; inflorescence without involucre, terminal, often elongating in fruit, or axillary.8  Diarthron    草瑞香属
4(2)Annual herbs, mainly branched well above base, roots not thickened; hypogynous disk very reduced or absent; inflorescence terminal, lax, elongated, spikelike; calyx tube 2-4 mm.7  Thymelaea    欧瑞香属
+Perennials, if herbaceous or suffrutescent then with stems rarely branched above base and roots often thickened; hypogynous disk present; inflorescence a compact raceme, spike, or head, sometimes grouped into panicles, or axillary fascicles subtended by n(5)
5(4)Style long, stigma narrowly terete, ± clavate.6  Edgeworthia    结香属
+Style very short or obscure, stigma capitate(6)
6(5)Inflorescence sessile, or if pedunculate, flower buds not enclosed within an involucre; calyx lobes spreading at anthesis(7)
+Inflorescences long pedunculate, flower buds enclosed in conspicuous calyxlike involucre; calyx lobes erect at anthesis(8)
7(6)Hypogynal disk of distinct scales, inflorescences racemose, paniculate, or spicate, less often capitate; leaves opposite or alternate.2  Wikstroemia    荛花属
+Hypogynal disk annular and oblique or cup-shaped, margins entire or lobed to parted or developed on one side, inflorescences capitate or fascicled, rarely spicate or racemose; leaves usually alternate, rarely opposite.3  Daphne    瑞香属
8(6)Inflorescence an axillary 5-10-flowered head, calyx white within.4  Eriosolena    毛花瑞香属
+Inflorescence a panicle of many terminal and subterminal (3 or)4(-7)-flowered heads, calyx red within.5  Rhamnoneuron    鼠皮树属
   Lower Taxon
  • Aquilaria  Lamarck  沉香属
  • Daphne  Linnaeus  瑞香属
  • Diarthron  Turczaninow  草瑞香属
  • Edgeworthia  Meisner  结香属
  • Eriosolena  Blume  毛花瑞香属
  • Rhamnoneuron  Gilg  鼠皮树属
  • Stellera  Linnaeus  狼毒属
  • Thymelaea  Miller  欧瑞香属
  • Wikstroemia  Endlicher  荛花属