Stenogonum

Nuttall

Proc. Acad. Nat. Sci. Philadelphia 4: 19. 1848.

Common names: Two-whorl buckwheat
Etymology: Greek stenos, narrow, and gonos, seed, alluding to achene
Synonyms: Eriogonum sect. Stenogonum (Nuttall) Kuntze
Treatment appears in FNA Volume 5. Treatment on page 431. Mentioned on page 220, 433.
 TaxonIllustrator 
FNA5 P43 Stenogonum salsuginosum.jpegStenogonum salsuginosum
Goodmania luteola
Gilmania luteola

Herbs, annual; taproot slender. Stems arising directly from the root, spreading to decumbent, solid, not fistulose or disarticulating into ringlike segments, glabrous or minutely strigose or glandular. Leaves usually persistent through anthesis, basal and rosulate or basal and cauline, alternate; petiole present (basal leaves); blade narrowly lanceolate to oblanceolate or spatulate to orbiculate, margins entire. Inflorescences terminal, cymose; branches mostly dichotomous, not brittle or disarticulating into segments, round, minutely strigose or glandular, glabrous; bracts 3 per node, connate basally, scalelike, triangular, not awn-tipped, glabrous or sparsely glandular. Peduncles straight or flexed, slender to filiform, sometimes absent. Involucral-bracts in 2 whorls of 3, connate proximally, lanceolate, not awn-tipped. Flowers (6–) 9–15 per involucral cluster at any single time during full anthesis; perianth yellow to reddish yellow, broadly campanulate when open, narrowly urceolate when closed, pilose abaxially; tepals 6, monomorphic, entire apically; stamens 9; filaments basally adnate, glabrous; anthers yellow, oval. Achenes usually included, light-brown, not winged, 3-gonous, glabrous. Seeds: embryo curved. x = 20.

Distribution

w United States

Discussion

Species 2 (2 in the flora).

Stenogonum is clearly allied to Eriogonum subg. Ganysma, specifically E. trichopes and its close relatives. The genus is readily distinguished from Eriogonum by an involucre reduced to a series of two foliaceous whorls of three lanceolate bracts.

Key

1 Leaves basal; peduncles flexed; stems mostly erect, sparsely glandular Stenogonum flexum
1 Leaves basal and cauline; peduncles straight; stems mostly spreading, glabrous Stenogonum salsuginosum

"/2" is not declared as a valid unit of measurement for this property.

... more about "Stenogonum"
light-brown +
3-gonous +
James L. Reveal +
Nuttall +
stipelike +
awn-tipped +  and simple +
narrowly lanceolate;oblanceolate or spatulate +
not awn-tipped +
glandular +  and glabrous +
triangular +  and scale-like +
disarticulating +  and dichotomous +
not brittle +
glabrous +, glandular +  and strigose +
just below the soil surface or and above the soil surface +  and spreading +
Two-whorl buckwheat +
w United States +
Greek stenos, narrow, and gonos, seed, alluding to achene +
unisexual +  and bisexual +
disarticulating +  and solid +
decumbent to erect +  and prostrate +
unwinged +  and winged +
black +, red +, brown +  and yellowish +
exserted +  and included +
pubescent +  and glabrous +
spheroidal +, 4-gonous +, lenticular +, biconvex +, discoid +, 3-gonous +  and 2-gonous +
cymelike +, paniclelike +, racemelike +  and spikelike +
urceolate +, campanulate +, turbinate +, prismatic +  and cylindric +
nonmembranous +
alternate +  and rosulate +
persistent +
cauline +  and basal +
bractlike +
pubescent +  and glabrous +
lobed +, undulate +, crisped +, crenulate +  and entire +
not swollen +
orthotropous +
accrescent +
erect to deflexed +
filiform;flexed +
yellow;reddish yellow +
urceolate +  and campanulate +
accrescent +
fleshy +, indurate +  and membranous +
with extrafloral nectaries +  and not articulate +
homostylous +  and 3-carpellate +
Proc. Acad. Nat. Sci. Philadelphia +
reveal1977a +
, +  and solid +
slender;stout +
disarticulating +  and solid +
decumbent to spreading or erect +  and prostrate +
spreading +  and decumbent +
glandular +, strigose +  and glabrous +
not fistulose +
penicillate +, fimbriate +  and capitate +
deciduous +  and persistent +
2-lobed +  and cylindric +
coriaceous +  and membranous +
consisting of a series +  and tubular +
distinct +
erect;spreading or recurved +
spreading;erect +
Eriogonum sect. Stenogonum +
chambered +, , +  and solid +
Stenogonum +
Polygonaceae subfam. Eriogonoideae +
lobed +  and laciniate +
coriaceous +
persistent +
membranous +
pubescent +  and glabrous +
3 +  and 2 +