Dudleya cymosa subsp. marcescens

Moran

Madroño 14: 106, fig. 1. 1957,.

EndemicConservation concern
Synonyms: Dudleya marcescens (Moran) P. H. Thomson
Treatment appears in FNA Volume 8. Treatment on page 183. Mentioned on page 177, 180, 186.
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Caudices often branching, 0.2–0.7 cm diam. Leaves withering in summer; rosettes 8–15-leaved; blade green, oblanceolate, 1.5–3 (–5) × 0.5–1.5 cm, apex acute to subobtuse, surfaces not farinose, glaucous. Inflorescences: floral shoots 5–15-leaved, 4–10 cm; cincinni 1–2, (1–) 3–5-flowered, 1–4 cm. Petals bright-yellow, often marked with red, 10–14 × 2.5–3.5 mm. 2n = 34.


Phenology: Flowering spring.
Habitat: With moss and lichens in very thin soil on sheer north-facing cliffs
Elevation: 300-400 m

Discussion

Of conservation concern.

Subspecies marcescens is known from the Santa Monica Mountains, Ventura and Los Angeles counties; it is considered fairly threatened (California Native Plant Society, http://cnps.web.aplus.net/cgi-bin/inv/inventory.cgi). This is the most distinct and distinctive of the subspecies of Dudleya cymosa, very different from subsp. cymosa but more or less connected by subsp. ovatifolia, also in the Santa Monica Mountains. It differs in its slender caudex, small leaves, and few flowers, and is one of only two members of subg. Dudleya whose leaves wither in early summer and are not replaced until after the first rains, often in late fall. The other is D. parva, growing some 13 kilometers to the north. In habit, they resemble subg. Hasseanthus, which differs in its slow-growing underground stems with crowded leaves and its open flowers. As noted by M. Dodero (1996), these two also are paedomorphic forms.

Selected References

None.

Lower Taxa

None.
perigynous +  and hypogynous +
acute +  and subobtuse +
Reid V. Moran +
0.5cm +  and 3cm +
Echeveria cymosa +
3 cm30 mm <br />0.03 m <br /> (5 cm50 mm <br />0.05 m <br />) +
1 cm10 mm <br />0.01 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
1.5 cm15 mm <br />0.015 m <br /> (3 cm30 mm <br />0.03 m <br />) +
lobed +  and toothed +
oblanceolate +
0.1 cm1 mm <br />0.001 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
0.5 cm5 mm <br />0.005 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
1-3 times bifurcate also with lateral branches +, simple +  and not twisted +
bifurcate +
1-3 times bifurcate also with lateral branches +
0.3 cm3 mm <br />0.003 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
0.3 cm3 mm <br />0.003 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
0.2 cm2 mm <br />0.002 m <br /> (1 cm10 mm <br />0.01 m <br />) +
0.2 cm2 mm <br />0.002 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
elongate +
1cm;3.5cm +
whorled +, opposite +  and alternate +
(1-)3-5-flowered +
5 cm50 mm <br />0.05 m <br /> (17 cm170 mm <br />0.17 m <br />) +
1 cm10 mm <br />0.01 m <br /> (4 cm40 mm <br />0.04 m <br />) +
5-gonal +  and tubular +
2-4-branched +
obpyramidal +
300-400 m +
30 cm300 mm <br />0.3 m <br /> (50 cm500 mm <br />0.5 m <br />) +
4 cm40 mm <br />0.04 m <br /> (10 cm100 mm <br />0.1 m <br />) +
0.1 cm1 mm <br />0.001 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
branched +  and simple +
erect;pendent +
erect;spreading +
With moss and lichens in very thin soil on sheer north-facing cliffs +
axillary +  and terminal +
sessile +, petiolate +  and subclasping +
alternate +  and crowded +
persistent +
spreading +  and ascending +
usually connivent;adjacent +
wider than tall +
semi-inferior +  and superior +
tenuinucellate +, crassinucellate +  and bitegmic +
0.5 cm5 mm <br />0.005 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
perigynous +  and hypogynous +
bright-yellow +
10mm;14mm +
ascending +  and erect +
0.1 cm1 mm <br />0.001 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
Flowering spring. +
(3-)4-5(-12)[-30+]-carpellate +
not gibbous +
cross-ribbed +  and ribbed +
1 +  and many +
Endemic +  and Conservation concern +
adnate +  and free +
antipetalous +
2-branched +  and simple +
distinct +
glaucous +  and not farinose +
Dudleya marcescens +
Dudleya cymosa subsp. marcescens +
Dudleya cymosa +
subspecies +
outcurved +
cylindric +  and 5-gonal +
perennial +, biennial +  and annual +