Malacothrix
desertdandelion, malacothrix
1–15 (usually from basal rosettes), usually erect, sometimes ± prostrate, usually branched (scapiform in M. californica), usually glabrous (sometimes piloso-hirsute, stipitate-glandular, or tomentose to arachnose or puberulent, at least proximally or in leaf axils).
usually basal and cauline;
sessile;
blades mostly oblong or lanceolate to obovate, oblanceolate, or spatulate (often pinnately lobed), ultimate margins entire or ± dentate (faces usually glabrous, sometimes piloso-hirsute or tomentose to arachnose or puberulent).
not inflated distally, usually bracteate.
usually broadly to narrowly campanulate, sometimes hemispheric, (5–22+ ×) 2–22+ mm diam.
flat to ± convex, pitted or smooth, sometimes bristly, epaleate.
15–270;
corollas yellow or white (sometimes reddish or lavender abaxially; outer ligules exserted 1–15 mm).
either (without calyculi) 25–80+ in 4–6+ series and orbiculate to oblong, lance-oblong, lanceolate, or linear, unequal, or (with calyculi) 12–25+ in 2–3 series and oblong or lanceolate to linear, subequal;
margins ± hyaline, 0.05–2.5 mm, apices obtuse to acute or acuminate.
0 (outer phyllaries intergrading with inner) or of 3–30+, ± deltate or lanceolate to linear or subulate, subequal to unequal bractlets (in 1–2 series distinct from phyllaries, margins usually hyaline, faces usually glabrous, sometimes arachnose, rarely stipitate-glandular).
usually in corymbiform to paniculiform arrays (borne singly in M. californica).
(monomorphic) stramineous to brown or purplish brown, ± prismatic or cylindro-fusiform, not beaked, ribs 15 (often 5 more prominent than others, apices of ribs sometimes projecting and forming coronas subtending pappi), usually glabrous (sometimes minutely hirtellous or muriculate);
pappi 0, or (single or double) persistent, whitish, crenate crowns or rings of (1–)8–25+ teeth (mostly 0.05–0.1 mm) plus 0–6, coarse, smooth bristles (setiform scales), all in ± 1 series, subtending (i.e., exterior to) the readily falling, inner (or single and only) pappi of 15–35, basally coherent, white, fine, smooth to barbellulate or (proximally) ± plumose bristles in 1 series (falling all together or in groups).
= 7, 9.
Malacothrix
Species 20 (18 in the flora).
(Discussion copyrighted by Flora of North America; reprinted with permission.)
1. Perennials (sometimes flowering first year) | → 2 |
1. Annuals | → 3 |
2. Corollas medium yellow; persistent pappi 0 | M. incana |
2. Corollas white (usually each with abaxial purple stripe); persistent pappi of fimbriate crowns or 20–25, blunt teeth (0.01–0.05 mm) plus 0 bristles | M. saxatilis |
3. Involucres hemispheric; phyllaries orbiculate (outer) to oblong or linear, hyaline margins 1–2.5 mm wide | M. coulteri |
3. Involucres usually ± campanulate (to hemispheric in M. sonchoides); bractlets of calyculi and/or phyllaries ovate to lanceolate, linear, or subulate, hyaline margins 0.05–0.3(–1) mm wide | → 4 |
4. Stems seldom branched (heads usually borne singly on scapiform peduncles); cypsela ribs: 5 more prominent than others | M. californica |
4. Stems branched (heads usually in corymbiform to paniculiform arrays); cypsela ribs ± equal, or 5 more prominent than others | → 5 |
5. Cauline leaves not or seldom notably reduced distally (Channel Islands, California) | → 6 |
5. Cauline leaves usually reduced distally (M. clevelandii and M. similis are known from Channel Islands, California) | → 9 |
6. Persistent pappi usually 0, rarely of 1–2 bristles; pollen 70–100% 3-porate | → 7 |
6. Persistent pappi of 15–20 teeth (0.01–0.1 mm) plus 1–2 bristles; pollen 70–100% 4-porate | → 8 |
7. Stems erect or ± prostrate (forming mats); proximal cauline leaves usually fleshy (lobes nearly equal, apices obtuse); San Miguel, Santa Cruz, and Santa Rosa islands | M. indecora |
7. Stems erect (not forming mats); proximal cauline leaves usually not fleshy (lobes usually unequal, apices acute or obtuse); Anacapa, San Clemente, San Nicolas, and Santa Barbara islands | M. foliosa |
8. Calyculi 0; phyllaries 31–49 in 5–6+ series, hyaline margins 0.6–1 mm wide; Anacapa and Santa Cruz islands, California | M. squalida |
8. Calyculi of 7–11 bractlets; phyllaries 9–13 in 2–3 series, hyaline margins 0.1–0.2 mm wide; Anacapa Island, California | M. junakii |
9. Corollas 4–10 mm; outer ligules exserted 1–4 mm | → 10 |
9. Corollas (7–)10–23+ mm; outer ligules exserted 5–15+ mm | → 14 |
10. Proximal cauline leaves (pinnately lobed, lobes 3–5 pairs, ± equal, bases white-hairy) ± fleshy; persistent pappi of crenate crowns plus 0 bristles; pollen 70–100% 3-porate. | M. phaeocarpa |
10. Proximal cauline leaves (pinnately lobed or not) not fleshy; persistent pappi of 8–24+ teeth plus 1–2 bristles; pollen 3- or 4-porate | → 11 |
11. Proximal cauline leaves oblanceolate to lance-linear; corollas pale yellow; cypselae ± cylindro-fusiform or prismatic, 1.2–1.8 mm (ribs extending to apices, 5 more prominent than others); persistent pappi of 14–24+ needlelike teeth plus 1 bristle (mainly California) | → 12 |
11. Proximal cauline leaves obovate to narrowly oblanceolate; corollas white or pale yellow; cypselae ± cylindro-fusiform, 1.7–2.3 mm (ribs not extending to apices, ± equal); persistent pappi of 8–18 teeth plus 1–2 bristles (Arizona, California, Nevada) | → 13 |
12. Stems branched mostly distally, glabrous; cauline leaves: margins usually dentate; cypselae (stramineous to brown) 1.2–1.8 mm; pollen 3-porate (mean diam. 25 µm) | M. clevelandii |
12. Stems branched mostly proximally; cauline leaves: margins usually entire; cypselae 1.4–1.7 mm (purplish brown); pollen 4-porate (mean pollen diam. 30 µm) | M. similis |
13. Corollas white or pale yellow; cypselae 1.7–2 mm (bases slightly expanded, distal 0.3 mm smooth); pollen 70–100% 3-porate | M. sonorae |
13. Corollas usually yellow, sometimes white; cypselae 1.7–2.3 mm (bases not expanded, distal 0.1–0.2 mm smooth); pollen 70–100% 4-porate | M. stebbinsii |
14. Proximal cauline leaves pinnately lobed (lobes 2–6+ pairs, filiform or triangular to oblong, subequal to unequal, apices acute), not fleshy, ultimate margins dentate or entire; cypsela ribs ± equal | → 15 |
14. Proximal cauline leaves pinnately lobed (lobes 3–8 pairs, ± oblong to triangular, ± equal, apices obtuse or acute), ± fleshy, ultimate margins usually dentate; cypsela ribs ± equal or 5 more prominent than others | → 16 |
15. Proximal cauline leaves usually pinnately lobed (lobes filiform); receptacles bristly; cypselae ± cylindro-fusiform (sometimes weakly 5-angled, ribs extending to apices). | M. glabrata |
15. Proximal cauline leaves sometimes pinnately lobed (lobes relatively broad, triangular to deltate); receptacles not bristly; cypselae ± cylindro-fusiform (ribs not extending to apices, distal 0.3 mm of cypselae smooth) | M. fendleri |
16. Corollas white or yellow (usually with lavender abaxially); cypselae 1.2–2 mm; persistent pappi 0 | M. floccifera |
16. Corollas lemon or medium yellow; cypselae 1.8–4 mm; persistent pappi of 12–25+ irregular, blunt teeth plus 0–6 bristles | → 17 |
17. Distal cauline leaves narrowly triangular to linear (bases usually ± dilated, ± clasping); persistent pappi of crenate crowns or 12–25+ teeth plus 0 bristles. | M. sonchoides |
17. Distal cauline leaves ± elliptic to linear (bases narrowly cuneate); persistent pappi of 12–15 teeth plus 0–6 bristles | M. torreyi |
CA
OR
Flora NW
PNW Herbaria
WildflowerSearch
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USDA Plants Database
