Boerhavia triquetra

S. Watson

Proc. Amer. Acad. Arts 24: 69. 1889.

Treatment appears in FNA Volume 4. Treatment on page 24. Mentioned on page 19, 23.

Herbs, annual; taproot tapered, soft or ± woody. Stems erect or ascending, occasionally decumbent, moderately or profusely branched, primarily distally, 1–5 dm, minutely puberulent with bent hairs basally, glabrous or minutely puberulent distally. Leaves mostly in basal 1/2 of plant; larger leaves with petiole 4–8 [–15] mm, blade broadly ovate or oval to lanceolate, 10–21 [–35] × 6–8 [–13] mm (distal leaves smaller, proportionately narrower), adaxial surface usually glabrous, rarely minutely puberulent, abaxial surface paler than adaxial, glabrous, neither surface punctate, base round [obtuse], margins shallowly sinuate, apex acute, obtuse, or round. Inflorescences terminal or axillary, forked ca. 3–6 times ± evenly (or clearly unevenly), diffuse, with sticky internodal bands; branches usually terminating in umbels or flowers borne singly, usually well beyond leaves. Flowers: pedicel 0.3–4.5 mm; bracts at base of perianth quickly deciduous, 2, linear-lanceolate to lanceolate [ovate], 0.5–0.6 mm; perianth whitish to pale-pink or purplish, campanulate beyond constriction, 1 mm; stamens 2–3, included or barely exserted. Fruits 1–7 per umbel, straw colored or gray-brown, obpyramidal, 2.5–3.1 × 1.3–1.9 mm (l/w: 1.6–2.1), base stipelike, apex round-truncate, glabrous; ribs 3–4 (–5), acute or winglike, tapering to pedicel, slightly rugose or undulate near sulci; sulci 0.5–1 times as wide as base of ribs, coarsely transversely rugose, smooth or very faintly papillate.


Phenology: Flowering summer–late fall.
Habitat: Sandy or gravelly areas in deserts
Elevation: [0-]100-300 m

Distribution

V4 34-distribution-map.gif

Ariz., Calif., Mexico (Baja California), Mexico (Baja California Sur), Mexico (Sonora)

Discussion

Boerhavia triquetra, very narrowly defined here by a predominance of 3- and 4-ribbed fruits, is uncommon in the flora, known to occur only on low deserts near the Colorado River and southward around the Sea of Cortez. The species has few- or 1-flowered terminal inflorescences. Its relationship to, and distinctness from, B. intermedia, needs clarification. In the area of the type locality, Bahia de los Angeles, on the east coast of Baja California, some plants have only 3- and 4-winged fruits, whereas most will have 3-, 4-, and some 5-winged fruits. The five-winged fruits do not differ from those of B. intermedia, a species common on the peninsula. Intergradient plants occur on the peninsula and on islands in the gulf.

Selected References

None.

Lower Taxa

None.

"thin" is not a number."dm" is not declared as a valid unit of measurement for this property.

... more about "Boerhavia triquetra"
puberulent +  and glabrous +
Richard W. Spellenberg +
S. Watson +
glutinous +
symmetric +  and asymmetric +
deciduous +
stipelike +  and round +
unequal +
woody +, leathery +  and fleshy +
2.1 cm21 mm <br />0.021 m <br /> (3.5 cm35 mm <br />0.035 m <br />) +
0.8 cm8 mm <br />0.008 m <br /> (1.3 cm13 mm <br />0.013 m <br />) +
1 cm10 mm <br />0.01 m <br /> (2.1 cm21 mm <br />0.021 m <br />) +
oval;lanceolate +
6mm;8mm +
deciduous +  and persistent +
distinct +
linear-lanceolate +  and lanceolate +
minute +  and not accrescent +
corollalike +  and petaloid +
Ariz. +, Calif. +, Mexico (Baja California) +, Mexico (Baja California Sur) +  and Mexico (Sonora) +
[0-]100-300 m +
curved +  and straight +
inconspicuous +  and showy +
1 +  and 80 +
chasmogamous +  and bisexual +
gray-brown +  and straw colored +
2.5mm;3.1mm +
1 (?) +  and 7 (?) +
obpyramidal +
coriaceous +
0.13 cm1.3 mm <br />0.0013 m <br /> (0.19 cm1.9 mm <br />0.0019 m <br />) +
Sandy or gravelly areas in deserts +
thyrsiform +, cymose +  and pedunculate +
axillary +  and terminal +
3-6 times diffuse with sticky internodal bands +
unequal +
(4-)5-lobed +
pubescent +  and glabrous +
0.03 cm0.3 mm <br />3.0e-4 m <br /> (?) +  and 0.45 cm4.5 mm <br />0.0045 m <br /> (?) +
campanulate +
constricted +
1 cm10 mm <br />0.01 m <br /> (?) +
0.8 cm8 mm <br />0.008 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
0.4 cm4 mm <br />0.004 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
Flowering summer–late fall. +
Proc. Amer. Acad. Arts +
glandular-pubescent +, glabrous +  and smooth +
3 +  and 4 +
undulate +, tapering +, winglike +  and acute +
thick +  and thin +
fibrous;fleshy +
membranaceous +
ribbed +, 10-ribbed +  and 5-ribbed +
pubescent +, glabrous +  and warty +
wrinkled +
exserted +  and included +
ascending +  and erect +
fusiform +  and linear +
filiform +
papillate +  and rugose +
0.5-1 times as wide as base +
woody +  and soft +
Boerhavia triquetra +
Boerhavia +
species +
umbellate +, subumbellate +, spicate +  and cymose +
capitate +  and subcapitate +
singly +  and racemose +
gland-tipped +
expanded +
pubescent +, glabrous +  and glandular +
fusiform +  and ropelike +