Oxytheca

Nuttall

Proc. Acad. Nat. Sci. Philadelphia 4: 18. 1848.

Common names: Puncturebract
Etymology: Greek oxys, sharp, and theke, case, alluding to awned involucre
Synonyms: Eriogonum sect. Oxytheca (Nuttall) Roberty & Vautier
Treatment appears in FNA Volume 5. Treatment on page 434. Mentioned on page 221, 435.
 TaxonIllustrator 
FNA5 P44 Oxytheca dendroidea s dendroidea.jpegOxytheca dendroidea subsp. dendroidea
Acanthoscyphus parishii var. parishii
Sidotheca caryophylloides

Herbs, annual; taproot slender. Stems arising directly from the root, erect to spreading, slender, solid, not fistulose or disarticulating into ringlike segments, sparsely to densely glandular. Leaves persistent through anthesis or quickly deciduous, essentially basal, rosulate; petiole indistinct; blade linear to spatulate, margins entire. Inflorescences terminal, cymose; branches mostly dichotomous, not brittle or disarticulating into segments, round, glabrous or sparsely glandular; bracts 3–5, distinct or connate basally, opposite and linear to narrowly triangular, positioned to side of node, 3-lobed and broadly triangular, or forming a perfoliate disk, leaflike to scalelike, awned, occasionally glandular, glabrous to pubescent. Peduncles present or absent, erect or deflexed, slender or stout. Involucres 1 per node, not ribbed, tubular, narrowly turbinate; teeth (3–) 4, erect to spreading, awn-tipped. Flowers 2–10 per involucre at any single time during full anthesis; perianth white to rose or greenish yellow, broadly campanulate when open, narrowly urceolate when closed, glabrous or pubescent abaxially; tepals 6, connate 1/4–1/3 their length, monomorphic or dimorphic, entire apically; stamens 9; filaments basally adnate, glabrous or minutely papillate basally; anthers cream to pink or red, ellipsoid to oval. Achenes usually included, light to dark-brown or maroon, not winged, globose-lenticular, glabrous. Seeds: embryo curved. x = 20.

Distribution

w North America, s South America

Discussion

Species 3 (3 in the flora).

Oxytheca is allied to Eriogonum subg. Ganysma, specifically E. spergulinum and its close relatives. It is distinguished from Eriogonum by the awned involucral lobes. Several species of Oxytheca are food plants for the small dotted-blue butterfly (Philotiella speciosa).

Key

1 Inflorescence bracts connate into perfoliate disk; leaf blades glabrous, with ciliate margins Oxytheca perfoliata
1 Inflorescence bracts not connate into perfoliate disk; leaf blades densely hirsute or strigose and sparsely glandular, without ciliate margins > 2
2 Involucres pedunculate at proximal nodes; awns of inflorescence bracts 0.2-0.5 mm; leaf blades linear to linear-oblanceolate Oxytheca dendroidea
2 Involucres subsessile; awns of inflorescence bracts 1-3 mm; leaf blades broadly oblanceolate to spatulate Oxytheca watsonii

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

... more about "Oxytheca"
light;dark-brown or maroon +
globose-lenticular +
cream +  and pink or red +
ellipsoid +  and oval +
James L. Reveal +
Nuttall +
stipelike +
awn-tipped +  and simple +
linear;spatulate +
pubescent +  and glabrous +
scale-like +  and leaflike +
disarticulating +  and dichotomous +
not brittle +
glandular +  and glabrous +
just below the soil surface or and above the soil surface +  and spreading +
Puncturebract +
w North America +  and s South America +
Greek oxys, sharp, and theke, case, alluding to awned involucre +
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 +
connate +  and free +
turbinate +  and tubular +
nonmembranous +
deciduous +  and persistent +
bractlike +
pubescent +  and glabrous +
lobed +, undulate +, crisped +, crenulate +  and entire +
connate +  and distinct +
glabrous +  and pubescent +
not swollen +
orthotropous +
accrescent +
curved +  and straight +
deflexed;erect +
erect to deflexed +
stout +  and slender +
white;rose or greenish yellow +
pubescent +  and glabrous +
urceolate +  and campanulate +
accrescent +
fleshy +, indurate +  and membranous +
with extrafloral nectaries +  and not articulate +
homostylous +  and 3-carpellate +
Proc. Acad. Nat. Sci. Philadelphia +
ertter1980a +
, +  and solid +
slender;stout +
disarticulating +  and solid +
decumbent to spreading or erect +  and prostrate +
erect +  and spreading +
pubescent +  and glabrous +
not fistulose +
slender +
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. Oxytheca +
chambered +, , +  and solid +
Oxytheca +
Polygonaceae subfam. Eriogonoideae +
1/4 +  and 1/3 +
lobed +  and laciniate +
coriaceous +
erect +  and spreading +
persistent +
membranous +
pubescent +  and glabrous +
3 +, 2 +  and 1 +