Contains 5 accepted taxa overall.

Characteristics
Spermacoce L.
FALSE BUTTONWEED
The delimitations of Borreria and Spermacoce are yet to be fully worked out, as previous circumscriptions are not monophyletic (Salas et al. 2015; Florentin et al. 2017).
Classification
GENTIANALES
Spermacoce
Citation
SPERMACOCE Linnaeus, Sp. Pl. 102. 1753.
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TYPE: Spermacoce tenuior Linnaeus Lectotypified by Britton & A. Brown, Ill. Fl. N. U.S., ed. 2. 3: 256. 1913.
Species
Scientific Name Common Name Herbarium Specimens Status Photos
Spermacoce glabra SMOOTH FALSE BUTTONWEED Native FACW (NWPL) FACW (DEP)
Spermacoce keyensis FLORIDA FALSE BUTTONWEED Native
Spermacoce latifolia OVAL-LEAF FALSE BUTTONWEED Not Native
Spermacoce prostrata PROSTRATE FALSE BUTTONWEED Native FACW (NWPL)
Spermacoce tetraquetra PINELAND FALSE BUTTONWEED Native
Identification Key
1.  Stems and leaves copiously short-pilose, pilose, or hispid
2
1.  Stems and leaves glabrous to sparingly pubescent
3
2.  Stems conspicuously winged, the wings 0.3-0.5 mm wide; leaves 1.5-4 times longer than wide, with 4-8 lateral veins; trichomes white to red
2.  Stems not winged; leaves (2.5)3-6 times longer than wide, with 1-3(4) lateral veins; trichomes white
3.  Calyx lobes 1-2 mm wide, 1.5-2.3 mm long; fruit glabrous; leaves with evident lateral veins
3.  Calyx lobes 0.2-0.7 mm wide, 0.3-1.5 mm long; fruit pubescent or glabrous
4
4.  Stem nodes usually with a pair of leaves only; calyx lobes 4, 0.2-0.4 mm wide
5
4.  Stem nodes commonly with sessile axillary fascicles of reduced leaves; calyx lobes 2-4, 0.4-0.7 mm wide
7
5.  Stems, leaves, calyx-lobes, and-or flower buds generally plain green without red coloration; leaves usually lacking evident lateral veins; calyx lobes (0.7)1-1.3 mm long, conspicuous, enclosing the corolla or exserted beyond the corolla
5.  Stems, leaves, calyx-lobes, and-or flower buds commonly suffused with red or pink, sometimes plain green without red; leaves commonly with evident lateral veins; calyx lobes 0.3-0.8 mm long, inconspicuous, the corolla exserted beyond the calyx lobes
6
6.  Stem glabrous; corolla lobes 0.5-1 mm long, only slightly longer than the calyx lobes; fruit 1-2 mm long, glabrous to pubescent
6.  Stem usually pubescent below the nodes; corolla lobes 2-4 mm long, more than 2 times longer than the calyx lobes; fruit 2-3 mm long, pubescent
7.  Leaves 0.8-2 cm wide, 2-4(4.5) times longer than wide
7.  Leaves 0.1-1 cm wide, (3.5)4-10 times longer than wide
8
8.  Corolla lobes 0.4-0.8 mm wide, 0.4-1 mm long; anthers 0.4-0.7 mm long; fruit (including persistent calyx lobe) 1.5–2.5 mm long
8.  Corola lobes 0.8-1.2 mm wide, 1-2.5 mm long; anthers 0.8-1.1 mm long; fruit (including persistent calyx lobe) 2.5-5 mm long
8
9.  Stems and branches many from the base of the plant, weakly lax to erect; deltoid prickles (0.1–0.5 mm long) along leaf blade midvein usually absent or 1-2 at the blade base; corolla lobe 1.5-2.5 mm long; fruit (including persistent calyx lobe) 2.5-4 mm long, dehiscent, somewhat open or cylindric, usually 2-seeded
9.  Stems single or many (especially when mowed) from the base of the plant, typically few to unbranched in the basal 1⁄2 of the plant, mostly erect (unless mowed); corolla lobe 1-1.5 mm long; fruit (including persistent calyx lobe) 4-5 mm long, indehiscent, flattened, usually 1-seeded with the other locule abortive
Genus Synonyms
Synonym Full Citation Basionym Type
Arbulocarpus Arbulocarpus Tennant, Kew Bull. 1957: 386. 1958. TYPE: Arbulocarpus sphaerostigmus (A. Richard) Tennant (Hypodematium sphaerostigmum A. Richard) Substitute name for Hypodematium A. Richard 1848, non Kunze 1833.
Chaenocarpus Chaenocarpus Necker ex A. Jussieu, in Cuvier, Dict. Sci. nat., ed. 2. 8: 50. 1817. TYPE: Non designatus.
Dichrospermum Dichrospermum Bremekamp, Bull. Jard. Bot. Etat 22: 75. 1952. TYPE: Dichrospermum congense Bremekamp
Hypodematium Hypodematium A. Richard, Tent. Fl. Abyss. 1: 348. 1848, non Kunze 1833. TYPE: Hypodematium sphaerostigmum A. Richard Lectotypified by Hiern, in Oliver, Fl. Trop. Afr. 3: 240. 1877. = Arbulocarpus Tennant 1958.
Paragophyton Paragophyton K. Schumann, Bot. Jahrb. Syst. 23: 454. 1897. TYPE: Paragophyton spermacocinum K. Schumann 1897.
Spermacoceodes Spermacoceodes Kuntze, Revis. Gen. Pl. 3(2): 123. 1898. TYPE: Non designatus.