1	Fruits glandular-pubescent or minutely pubescent; plants perennial		(2)
+	Fruits glabrous (rarely with some minute pubescence in sulci); plants annual or perennial		(4)
2 (1)	Leaves mostly distributed throughout plant; inflorescences axillary or terminal; branches spreading-villous or hispid to minutely and finely pubescent; flowers usually more than 5 per cluster; fruits narrowly obovate and tapering at both ends or clavate, apex round or narrowly round-conic		2 Boerhavia coccinea
+	Leaves mostly concentrated in basal 1/2 of plant; inflorescences mostly terminal; branches glabrate or glabrous; flowers usually borne singly or up to 5 per cluster, occasionally more; fruits oblong-clavate or obpyramidal, apex round, broadly conic, or truncate		(3)
3 (2)	Perianths wine red or brick red, 2-4.5 mm; stamens well exserted; flowers usually borne singly on slender pedicels; fruits oblong-clavate, minutely pubescent, some- times with minute gland-tipped hairs		3 Boerhavia gracillima (in part)
+	Perianths purplish red to reddish pink or nearly white, 1-1.5 mm; stamens included or barely exserted; flowers usually in tight clusters of 2-5 at ends of branches; fruits obpyramidal, conspicuously stipitate-glandular		1 Boerhavia diffusa
4 (1)	Plants perennial; fruit ribs rounded or bluntly round-angled		(5)
+	Plants annual; fruit ribs obtusely to acutely angled, ribs sometimes winglike, rarely bluntly round-angled		(8)
5 (4)	Bracts at base of perianths soon deciduous after anthesis; perianths wine red to brick red; sulci of fruit usually smooth		3 Boerhavia gracillima (in part)
+	Bracts at base of perianths persistent; perianths red-pink, pink-lavender, pink, or white; sulci of fruit smooth or papillate		(6)
6 (5)	Leaves linear to lanceolate, rarely ovate; perianths 4-7 mm; stamens usually 5; surface of sulci smooth.		6 Boerhavia linearifolia
+	Leaves ovate to round; perianths 2.5-10 mm; stamens 3-8; surface of sulci minutely papillate		(7)
7 (6)	Perianths 5-10 mm; stamens (4-)5-8; edges of fruit ribs rounded, not overhanging sulci		4 Boerhavia anisophylla
+	Perianths 2.5-3 mm; stamens 3-5; edges of fruit ribs sharp, slightly over- hanging sulci		5 Boerhavia ciliata
8 (4)	Branches of inflorescence densely glandular-villous, rarely minutely pubescent or glabrous, without sticky bands on distal internodes; bracts at base of perianth 1.5-4 mm, ovate (occasionally lance-acuminate in B. wrightii), persistent; fruits 4- or 5-ribbed, ribs never winglike		(9)
+	Branches of inflorescence usually glabrous, sometimes minutely pubescent but not glandular, often with sticky bands on distal internodes; bracts at base of perianth 0.4-1.8 mm, usually lanceolate or narrower, deciduous; fruits (3-)5-ribbed, ribs sometimes winglike		(10)
9 (8)	Fruits 4(-5)-ribbed; inflorescences racemose or spicate, axis 10-35 mm		12 Boerhavia wrightii
+	Fruits 5-ribbed; inflorescences subcapitate or capitate, axis 0-2.5 mm		13 Boerhavia purpurascens
10 (8)	Terminal portions of inflorescences spicate or racemose		(11)
+	Terminal portions of inflorescences subracemose, subumbellate, umbellate, or capitate, or flowers borne singly		(13)
11 (10)	Fruits broadly obovoid (l/w: usually 1.7-2.1), usually overlapping in inflorescence; sulci and ribs slightly rugose; sulci usually about 0.5 times as wide as base of ribs; stems usually glandular and spreading-pilose basally		14 Boerhavia spicata
+	Fruits narrowly obovoid or obpyramidal (l/w: usually 2.1-3.1), overlapping in inflorescence or remote; sulci and ribs slightly rugose to smooth; sulci 0.1-1 times as wide as base of ribs; stems puberulent, often sparsely pilose, rarely glandular basally		(12)
12 (11)	Epidermal surface of sulci papillose; sulci 0.5-1 times as wide as base of ribs; sides of ribs strongly rugose		15 Boerhavia torreyana
+	Epidermal surface of sulci glabrous; sulci 0.1-0.3 times as wide as base of ribs; sides of ribs smooth or slightly rugose		16 Boerhavia coulteri
13 (10)	Fruits 3-4(-5)-ribbed, ribs acute or winglike		(14)
14 (13)	Inflorescences capitate clusters on short peduncles among leaves and terminal on branches; fruit tapering to stipelike base distal to pedicels		11 Boerhavia pterocarpa
+	Inflorescences repeatedly forked, ending in umbels or single flowers, usually well beyond leaves; fruit tapering to pedicels, without stipelike base		9 Boerhavia triquetra 28!-!Fruits (3-)5-ribbe
15	Sulci of fruits smooth or very slightly rugose; fruits with 5 winglike ribs		10 Boerhavia megaptera
+	Sulci of fruits slightly to prominently rugose; fruits with (4-)5 angular ribs		(16)
16 (15)	Terminal flower clusters usually precise umbels, all pedicels attaching at 1 node; occasionally terminal inflorescences 1-flowered; fruits 2-3.2 mm		8 Boerhavia intermedia
+	Terminal flower clusters irregularly umbellate or subracemose, at least some pedicels attaching well below others; terminal inflorescences rarely 1-flowered; fruits 2.7-4 mm		7 Boerhavia erecta