Present on Pacific Islands?  yes

Threat only at high elevations?  no

Other Latin names:  Borreria ovalifolia M. Martens & Galeotti, Spermacoce ernstii Fosberg & D. Powell

Common name(s): [more details]

English: broadleaf false buttonweed

Habit:  herb

Description: 

Genus: "Annual or perennial herbs or small subshrubs; stems prostrate or erect, usually 4-angled, glabrous to hispid or scabrid.  Leaves opposite or pseudowhorled, usually lanceolate to ovate or elliptic, sessile or petiolate, stipules adnate to petioles, forming a sheath, margins with 1 to numerous filiform setae.  Flowers usually small, perfect, sessile, in axillary or terminal, usually many-flowered clusters subtended by 1-2 or more pairs of bract-like leaves, stipule-derived bracteoles with setae; hypanthium obovoid, turbinate, or sometimes with intermediate teeth; corolla funnelform or salverform, the tube usually very slender, the lobes (3) 4, spreading, valvate in bud; stamens 4, inserted on corolla tube or throat, usually exserted; ovary 2-celled, ovules 1 per cell, attached to middle of septum; style filiform, exserted.  Fruit either a 2-walved capsule dehiscing from apex downward and the septum disappearing, or of 2 dimorphic mericarps, one dehiscent, the other indehiscent.  Seeds 2, usually glossy brown, oblong, ellipsoid, or ovoid, usually reticulate, ventrally grooved" (Wagner et al., 1999; pp. 1171, 1173).

Species: "Annual herbs to 40 cm tall, often branched near the base and with few distal branches, leafy stems 0.5-2 mm thick, with 4 longitudinal ribs ca. 0.2 mm high, glabrous or minutely puberulent at the nodes; stipule sheath 0.5-3 mm high, often obscured by the inflorescences, with 3-11 awns 1-5 mm long.  Leaves opposite (occasionally pseudoverticillate) with 2-4 smaller axillary leaves, petioles 0-5 mm long, with lateral margins continuous with the leaf margins; leaf blades 6-48 mm long, 2-16 mm broad, elliptic to narrowly elliptic, elliptic-lanceolate or ovate-elliptic, apex acute, base acute to cuneate, drying membranaceous, brownish or dark green above, glabrous or with a few scabrous hairs above, subglabrous or with minute (0.1-0.2 mm) stiff hairs beneath, scabrous on the edges, 2º veins 2-5/side.  Inflorescences axillary and verticillate or terminal and subtended by 2-6 leaves, 2-4 mm high, 3-6 mm broad, with few (5-12) flowers.  Flowers with 4 calyx lobes 0.6-1.1 mm long, 0.1-0.2 mm broad, linear-aculeate, persisting; corolla minute.  Fruits ca. 2 mm long and 2 mm broad when opened, body of the capsule ca. 1.5 mm long, glabrous externally or minutely (o.05-0.1 mm) hispid distally; seeds (1.3-) 1.5-1.8 mm long, 0..8-0.9 mm broad, very finely reticulate (x 10) and minutely pitted (x 40), dark reddish brown" (Berger & Taylor, 1993; pp. 317-318).

Habitat/ecology:  In Costa Rica, "weedy plants of open sites in evergreen and partly deciduous areas of the Meseta Central, 900-1400 m elevation" (Berger & Taylor, 1993; pp. 317-318).

Propagation:  Seed

Native range:  "The species ranges widely, from the southern United States to South America, the West Indies, and the Old World" (Berger & Taylor, 1993; pp. 317-318).

Presence:

Pacific
Country/Terr./St. & Island group	Location	Cited status & Cited as invasive & Cited as cultivated & Cited as aboriginal introduction?	Reference & Comments
Commonwealth of the Northern Mariana Islands (US) Northern Mariana Islands	Rota Island	introduced	Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce (1979) (p. 278)
Commonwealth of the Northern Mariana Islands (US) Northern Mariana Islands	Saipan Island	introduced	Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce (1979) (p. 278)
Commonwealth of the Northern Mariana Islands (US) Northern Mariana Islands	Tinian Island	introduced	Raulerson, L. (2006) (p. 66)
Federated States of Micronesia Chuuk Islands	Puluwat (Pwonowót) Atoll	introduced invasive	Manner, H. I./Mallon, E. (1989) (p. 60) Voucher cited: Manner & Mallon 208 (GUAM) Rare
Federated States of Micronesia Kosrae Island	Kosrae Island	introduced invasive	Lorence, David H./Flynn, Tim (2005) (p. 22) Voucher ctied: Lorence 7872 (PTBG)
Federated States of Micronesia Yap Islands	Yap (Waqab) Island		Swarbrick, John T. (1997) (p. 97)
Guam Guam Island	Guam Island	introduced	Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce (1979) (p. 278)
Kiribati Tungaru (Gilbert) Islands	Abemama Atoll	introduced invasive	Space, James C./Imada, Clyde T. (2004) (p. 76) Voucher specimen collected: Imada 2003-138 (BISH 697750)
Kiribati Tungaru (Gilbert) Islands	Butaritari Atoll	introduced invasive	Space, James C./Imada, Clyde T. (2004) (p. 78) Voucher specimen collected: Imada 2003-53 (BISH 697668)
Kiribati Tungaru (Gilbert) Islands	Tarawa Atoll	introduced invasive	Space, James C./Imada, Clyde T. (2004) (p. 75) Voucher specimen collected: Imada 2003-42 (BISH 697657)
Marshall Islands Ratak Chain	Arno Atoll	introduced invasive	Vander Velde, Nancy/Vander Velde, Brian (2007) (p. 11) "Common to abundant; in lawns and ruderal areas".
Marshall Islands Ratak Chain	Maloelap Atoll		Vander Velde, Nancy (year unknown)
Palau Palau (main island group)	Angaur Island	introduced	Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce (1979) (p. 278)
Palau Palau (main island group)	Babeldaob Island		Raulerson, L./Rinehart, A. F./Falanruw, M. C. (1996)
Palau Palau (main island group)	Kayangel (Ngcheangel) Island	introduced	Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce (1979) (p. 278)
Palau Palau (main island group)	Koror Island	introduced	Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce (1979) (p. 278)
Palau Palau (main island group)	Peleliu Island	introduced	Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce (1979) (p. 278)

Pacific Rim
Country/Terr./St. & Island group	Location	Cited status & Cited as invasive & Cited as cultivated & Cited as aboriginal introduction?	Reference & Comments
Colombia Colombia	Colombia (Republic of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2007)
Costa Rica Costa Rica	Costa Rica (Republic of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2007)
Ecuador (Mainland) Ecuador	Ecuador (Republic of) (continental)	native	U.S. Dept. Agr., Agr. Res. Serv. (2007)
Mexico Mexico	Mexico (United Mexican States)	native	U.S. Dept. Agr., Agr. Res. Serv. (2007)
Nicaragua Nicaragua	Nicaragua (Republic of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2007)

Additional information:  Additional online information about Spermacoce ovalifolia is available from the Hawaiian Ecosystems at Risk project (HEAR).

Taxonomic information about Spermacoce ovalifolia may be available from the Germplasm Resources Information Network (GRIN).

References:

Berger, W., ed. 1993. Flora Costaricensis. Fieldiana Botany New Series, No. 33: Family #202 Rubiaceae.

Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce. 1979. A geographical checklist of the Micronesian dicotyledonae. Micronesica 15:1-295.

Lorence, David H./Flynn, Tim. 2005. Checklist of the plants of Kosrae. Unpublished checklist. National Tropical Botanical Garden, Lawai, Hawai‘i. 23 pp.

Manner, H. I./Mallon, E. 1989. An Annotated list of the vascular plants of Pulawat Atoll. Micronesica 22:23-63.

Raulerson, L. 2006. Checklist of Plants of the Mariana Islands. University of Guam Herbarium Contribution 40:1-69. .

Raulerson, L./Rinehart, A. F./Falanruw, M. C. 1996. A botanical reconnaissance of the proposed Compact-impact road alignment on Babeldaob Island, Republic of Palau. U. of Guam Herbarium Cont. No. 32. 78 pp.

Space, James C./Imada, Clyde T. 2004. Report to the Republic of Kiribati on invasive plant species on the islands of Tarawa, Abemama, Butaritari and Maiana. Cont. no. 2003-006 to the Pac. Biol. Surv. USDA Forest Service and Bishop Museum, Honolulu. 103 pp.

Swarbrick, John T. 1997. Weeds of the Pacific Islands. Technical paper no. 209. South Pacific Commission, Noumea, New Caledonia. 124 pp.

U. S. Government. 2006. Integrated Taxonomic Information System (ITIS) (on-line resource).

U.S. Dept. Agr., Agr. Res. Serv. 2007. National Genetic Resources Program. Germplasm Resources Information Network (GRIN). Online searchable database.

Vander Velde, Nancy. 0. Nancy Vander Velde, pers. com.

Vander Velde, Nancy/Vander Velde, Brian. 2007. Arno plants [preliminary working listing of plant species]. Unpublished checklist, 13 pp.