All Floras      Advanced Search
FOC Vol. 19 Page 326, 327, 328 Login | eFloras Home | Help
FOC | Family List | FOC Vol. 19 | Rubiaceae | Spermacoce

3. Spermacoce exilis (L. O. Williams) C. D. Adams, Fieldiana, Bot., n.s. 33: 316. 1993.

二萼丰花草 er e feng hua cao

Borreria exilis L. O. Williams, Phytologia 28: 227. 1974, based on B. gracilis L. O. Williams, Phytologia 26: 487. 1973, not Scheele (1844), nor Spermacoce gracilis Ruiz & Pavon (1798); B. repens Candolle; S. decandollei Deb & R. M. Dutta, nom. illeg. superfl.; S. mauritiana Gideon; S. repens (Candolle) Fosberg & D. A. Powell (1980), not Willdenow ex Chamisso & Schlechtendal (1828), nor Sessé & Mociño (1893), nor Larrañaga (1923).

Herbs, annual to perhaps perennial, slender, creeping to weakly ascending, to 30 cm tall; stems 4-angled, puberulent to glabrescent, angles winged, wings 0.1-0.5 mm wide, ciliate or ciliolate. Leaves subsessile to shortly petiolate; petiole to 1.5 mm, puberulent to glabrescent; blade drying membranous, ovate or elliptic-oblong, 0.7-30 × 4-15 mm, sparsely puberulent to glabrous throughout or pilose to hispid along midrib abaxially, base obtuse to cuneate, apex acute to obtuse; secondary veins 2 or 3 pairs; stipules pilosulous or hirtellous to glabrescent, sheath 0.5-1 mm, with 5-10 bristles 0.5-2 mm, often glandular. Inflorescences terminal and in uppermost leaf axils, 3-6 mm in diam., several to many flowered; bracts numerous, filiform, 0.5-1.5 mm. Calyx hirtellous to glabrescent; hypanthium portion obovoid, ca. 0.3 mm; lobes 2, linear-lanceolate to triangular, 0.4-0.9 mm. Corolla white, rotate to shortly tubular, 0.5-0.6 mm, outside glabrous, bearded in throat; lobes spatulate triangular, ± as long as tube. Capsules ellipsoid, weakly to strongly flattened at right angles to septum, 1-1.1 × 0.8-1 mm, glabrescent, membranous and sometimes somewhat hyaline, septicidal from apex then both valves loculicidal through septum or sometimes fragmenting; seeds brownish yellow, ellipsoid, ca. 0.8 × 0.4 mm, obtuse at both ends, shiny, surface apparently with numerous fine horizontal striations or ridges (at 10×; but actually with minute transverse pits, visible at 40×). Fl. and fr. almost year-round.

Naturalized in disturbed humid sites at low elevations. Hainan, Hong Kong, Taiwan [apparently native to the Neotropics but exact origin unknown; India, Indonesia, Nepal, Sri Lanka, Vietnam; Africa, Antilles, Australia, Central America, Indian Ocean islands (Mauritius), North America (Mexico), Pacific islands, N South America].

The seeds of this species were illustrated in detail by Chaw and Sivarajan (Bot. Bull. Acad. Sin., n.s., 30: 20, f. 28-30. 1989, as Spermacoce mauritiana). The taxonomy and circumscription of this adventive species here follows Burger and Taylor (Fieldiana, Bot., n.s., 33: 316. 1993). The illustration presented by Deb and Dutta (J. Econ. Taxon. Bot. 5(5): 1045, f. 2. 1984, as S. decandollei) seems to be based on a mixed collection of S. exilis and S. prostrata according to the circumscription of these species here. Both S. exilis and S. prostrata were formerly included in a broadly circumscribed, morphologically heterogeneous "Spermacoce ocymoides Burm. f." Several authors have concluded that this last name applies to a species found only in SE Asia and was incorrectly applied to American and adventive plants (Dessein, Syst. Stud. Spermacoceae (Ph.D. Diss.), University of Leuven, Belgium, 1-403. 2003, and references cited there); presumably the species treated by Bakhuizen f. in the Fl. Java is "true" S. ocymoides.

The description of Spermacoce exilis here includes observations from specimens from outside China; this species has probably been introduced to China more than once, thus it seems useful to include the variation found in adjacent regions that may yet be found in China.


Flora of China @
Browse by
Advanced Search

Flora of China Home




 |  eFlora Home |  People Search  |  Help  |  ActKey  |  Hu Cards  |  Glossary  |