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86. Spermacoce Linnaeus, Sp. Pl. 1: 102. 1753.
丰花草属 feng hua cao shu
Authors: Tao Chen & Charlotte M. Taylor
Bigelovia Sprengel (1824), not Smith (1819), nor Sprengel (1820), nor Bigelowia Rafinesque (1817), nor Candolle (1836, nom. cons.); Borreria G. Meyer (1818, nom. cons.), not Borrera Acharius (1810) [Fungi].
Herbs, annual or perennial, subshrubs, or low shrubs [rarely dioecious], unarmed. Raphides present. Leaves opposite, sometimes borne on very short axillary stems and these plus long-stem leaves appearing whorled or fascicled, without domatia; stipules persistent, fused to petiole bases or leaves, sheath truncate to broadly rounded or broadly triangular, usually thinly textured, with (1 or)2-11 bristles to multi-fimbriate, bristles occasionally glandular at apex. Inflorescences terminal and/or axillary, capitate or glomerulate, several to many flowered, sessile, bracteate, often partially enclosed in an expanded stipule sheath; bracts usually filiform-laciniate or stipuliform. Flowers sessile or subsessile, bisexual, monomorphic [or rarely distylous or unisexual]. Calyx limb deeply to completely 2- or 4[-8]-lobed, lobes sometimes unequal in pairs. Corolla white sometimes flushed with blue or pink [to sometimes pink, red, blue, or violet], salverform to funnelform, inside variously glabrous throughout, pubescent in throat or throughout, or usually with a ring of pubescence at stamen insertion; lobes 4, valvate in bud [and infrequently with abaxial horns or appendages]. Stamens 4, inserted in corolla throat to near base of tube, included or exserted; filaments short or developed; anthers dorsifixed. Ovary 2-celled, ovules 1 in each cell, axile near middle of septum; stigma capitate or 2-lobed with lobes short to linear, included or exserted. Fruit capsular, ellipsoid to subglobose, septicidally then loculicidally dehiscent with valves remaining joined at base [or sometimes separating completely or remaining connected at apex or partially schizocarpous with 1 valve loculicidal and 1 valve indehiscent], papery to thickly textured, with calyx limb persistent; seeds medium-sized, ellipsoid to subglobose, with ventral (i.e., adaxial) groove, with testa thin, smooth to variously ornamented including minutely pitted to rugose, ruminate, and/or reticulate; endosperm corneous or fleshy; cotyledons leaflike; hypocotyl terete, basiscopic.
About 250-300 species: widespread in tropical to warm temperate regions worldwide with several species widely naturalized; seven species (four introduced) in China.
These species were treated in the genus Borreria by W. C. Ko (in FRPS 71(2): 205-210. 1999); B. shandongensis as treated by Ko is here considered a synonym of Diodia teres. Borreria has traditionally been separated from Spermacoce based on fruit dehiscence, with both of the fruit valves dehiscent in Borreria vs. one dehiscent and one indehiscent in Spermacoce (vs. both indehiscent in Diodia), but based on pantropical surveys of this group and molecular data the majority of authors today include Borreria in Spermacoce (Verdcourt, Fl. Trop. E. Africa, Rub. (Pt. 1), 339-374. 1976; Deb & Dutta, J. Econ. Taxon. Bot. 5(5): 1037-1063. 1984; Chaw & Peng, J. Taiwan Mus. 40(1): 71-83. 1987; Dessein, Syst. Stud. Spermacoceae (Ph.D. Diss.), University of Leuven, Belgium, 1-403. 2003). The treatment here follows recent neotropical studies as to the separation of and names used for the adventive neotropical species (Burger & Taylor, Fieldiana, Bot., n.s., 33: 1-333. 1993; C. D. Adams, Flora Mesoamericana, in prep.). In particular, seed coat sculpture or texture is informative at the species level, though it must be observed at high magnification (Dessein, loc. cit.); Chaw and Sivarajan (Bot. Bull. Acad. Sin., n.s., 30: 15-24. 1989) illustrated seed coats of many Chinese species. Pollen is also informative in this group (e.g., Dessein et al., Australian J. Bot. 18: 367-382. 2005) but is incompletely studied.
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1 |
Corolla relatively small, with tube plus lobes 0.5-1 mm, with corolla tube shorter than, ± equal to, or slightly longer than calyx lobes; calyx lobes 2 or 4; mature fruit 0.6-1.1 × 0.3-1 mm |
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(2) |
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Corollas larger, with tube alone 0.5-10 mm and longer than calyx lobes; calyx lobes 4; mature fruit 1-5 × 1-3.5 mm |
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(3) |
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2 (1) |
Stem angles narrowly winged; leaf blade ovate or elliptic-oblong, 4-15 mm wide; seed coat apparently covered by numerous fine horizontal striations or ridges. |
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3 S. exilis |
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Stems smooth to angled, angles without wings; leaf blade narrowly elliptic-oblong to elliptic, 1-10 mm wide; seed coat with coarse rounded pits arranged in longitudinal (i.e., vertical) rows. |
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5 S. prostrata |
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3 (1) |
Fruit 1-2 × 1-1.5 mm; leaves linear-oblong or narrowly elliptic, 2.5-16 mm wide; corolla tubes 0.5-1.5 mm |
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(4) |
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Fruit 2.2-5 × 1.5-3.5 mm; leaves elliptic, ovate-oblong, oblong-ellipsoid, obovate, or spatulate, 3-40 mm wide |
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(5) |
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4 (3) |
Leaves linear-oblong, 2.5-6 mm wide; seeds appearing smooth. |
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6 S. pusilla |
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Leaves narrowly elliptic to lanceolate, 4-16 mm wide; seeds transversely ruminate-rugose with irregular deep grooves. |
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7 S. remota |
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5 (3) |
Leaf blade elliptic or ovate-oblong, usually widest near middle, 12-75 × 6-40 mm; plants often drying yellowish green; corolla tube 2-3 mm. |
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1 S. alata |
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Leaf blade oblong-elliptic, obovate, or spatulate, usually widest above middle, 10-30 × 3-18 mm; plants usually drying dull green to grayish; corolla tube 2.5-10 mm |
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(6) |
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6 (5) |
Mature seeds 2-2.5 mm, oblong to elliptic-oblong in outline, brown; corolla tube slender, 6.5-10 mm. |
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2 S. articularis |
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Mature seeds 2.2-3 mm, elliptic to elliptic-oblong in outline, black; corolla tube funnelform, 2.5-4.5 mm. |
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4 S. hispida |
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Lower Taxa
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