Lasthenia sect. Amphiachaenia

(Nuttall) R. Chan

Madroño 48: 205. 2002.

Basionym: Burrielia sect. Amphiachaenia Nuttall Trans. Amer. Philos. Soc., n. s. 7: 381. 1841
Synonyms: Undefined sect. Baeria Fischer & C. A. Meyer
Treatment appears in FNA Volume 21. Treatment on page 338. Mentioned on page 337, 341, 346.

Annuals or perennials. Leaves entire or ± toothed. Involucres campanulate to depressed-hemispheric, hemispheric, or obconic. Phyllaries ± persistent or falling with cypselae, distinct. Receptacles narrowly conic to conic (subulate in L. leptalea), muricate or papillate, glabrous. Ray corollas bright-yellow, laminae 2.5–16 mm, floral pigments turning deep red in dilute aqueous alkali. Disc corolla lobes 5; anther appendages deltate to sublanceolate or subulate (broadened distal to bases); style apices ± deltate with apical tufts of hairs and subapical fringes of shorter hairs. Cypselae to 4 mm; epappose or pappose. 2n = 16, 32, 48.

Distribution

w United States, nw Mexico

Discussion

Species 4 (4 in the flora).

Perennial lasthenias are found only in sect. Amphiachaenia. Epappose plants of sect. Amphiachaenia are more likely to be found in coastal populations and may constitute entire local populations.

Key

1 Stems glabrous proximally, villous distally; phyllaries usually 4–6, glabrous but for apices; receptacles subulate, papillate; anther appendages subulate; interior w California Lasthenia leptalea
1 Stems ± hairy throughout, sometimes more so distally; phyllaries 4–16, hairy; receptacles conic, muricate; anther appendages deltate to sublanceolate; Arizona, California, Oregon > 2
2 Perennials; coastal Oregon Lasthenia ornduffii
2 Annuals or perennials; coastal or inland Arizona, California, Oregon > 3
3 Annuals; leaves entire; pappi usually of (2–)4(–6) opaque, white (aging to brown), ovate-lanceolate, aristate scales, sometimes 0; Arizona, California (includingChannel Islands) Lasthenia gracilis
3 Annuals or perennials (if perennial, only in coastal California); leaves entire or with 3–5+ teeth; pappi 0, or of 1–7 translucent (rarely opaque), brown (rarely white), linear to subulate, aristate scales; n California, s Oregon Lasthenia californica
48 +, 32 +  and 16 +
deltate +  and sublanceolate or subulate +
not tailed +, rounded +  and obtuse +
connate +  and distinct +
subequal +
scarious +
usually ovate +  and lanceolate +
usually deltate +  and lanceolate +
paniculiform +, glomerate +  and corymbiform +
indeterminate +  and determinate +
Raymund Chan +  and Robert Ornduff† +
(Nuttall) R. Chan +
decurrent +
Burrielia sect. Amphiachaenia +
compound +  and simple +
winged;ribbed;winged;ribbed +
tuberculate +  and rugose +
barbellulate +  and barbellate +
yellow +  and orangish +
pappose +  and epappose +
hairy +  and glabrous +
4 +  and 18 +
papillate +
usually cylindric +  and obovoid +
fertile +  and bisexual +
fertile +  and bisexual +
w United States +  and nw Mexico +
hairy +  and glabrous +
pistillate +, staminate +  and neuter +
winged +  and beaked +
dispersed +
in more or less corymbiform arrays +  and singly +
indeterminate +
homogamous +  and heterogamous +
each +  and sessile +
0.3 cm3 mm <br />0.003 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
campanulate;depressed-hemispheric hemispheric or obconic +
0.25 cm2.5 mm <br />0.0025 m <br /> (1.6 cm16 mm <br />0.016 m <br />) +
sessile +  and petiolate +
toothed;entire +
papillate +
deltate +
dentate to pinnatifid or palmatifid +  and entire +
2-carpellate +
persistent +
of 1 +  and 12+ aristate +
aristate +, truncate +, laciniate +  and fimbriate +
scarious-margined +
weakly +  and flat +
glabrous +, glabrate +, woolly +  and tomentose +
3 +  and 18 +
papillate +  and muricate +
narrowly conic;conic +
chan2001b +  and chan2002a +
exalbuminous +
branched +  and simple +
sprawling +, prostrate +  and decumbent +
appendaged +  and truncate +
hirsutulous +  and glabrous +
papillate +
Undefined sect. Baeria +
Lasthenia sect. Amphiachaenia +
Lasthenia +
section +
campanulate +
toothed +  and entire +
40 cm400 mm <br />0.4 m <br /> (60 cm600 mm <br />0.6 m <br />) +
perennial +  and annual +
0 cm0 mm <br />0 m <br /> (40 cm400 mm <br />0.4 m <br />) +
shrub +  and subshrub +