Crocanthemum aldersonii

(Greene) Janchen in H. G. A. Engler et al.

in H. G. A. Engler et al., Nat. Pflanzenfam. ed. 2, 21: 305. 1925.

Common names: Alderson rushrose
Basionym: Helianthemum aldersonii Greene Erythea 1: 259. 1893
Synonyms: H. scoparium var. aldersonii (Greene) Munz
Treatment appears in FNA Volume 6. Treatment on page 402. Mentioned on page 401, 407, 408.

Subshrubs. Stems erect, 30–65 cm, glabrate to sparsely stellate-pubescent. Leaves cauline; petiole 0.5–1.5 mm; blade linear, 10–21 (–26) × 0.9–2 mm, surfaces stellate-pannose, lateral-veins obscure abaxially. Inflorescences terminal, broad panicles, branches spreading, usually curved, stellate-pannose; chasmogamous flowers 1–3 per branch; cleistogamous 0. Pedicels 5–13 mm, stellate-pubescent with no or sparse glandular-hairs; bracts 1–2.5 × 0.3–0.5 mm. Chasmogamous flowers: outer sepals linear, 1.3–2 (–2.8) × 0.3 mm, inner sepals 4.7–7 (–8) × 2–3 mm, apex acuminate or acute, calyx stellate-pubescent, hairs to 1 mm; petals obovate, 8–12 × 6–8 mm; capsules 3.5–4.3 × 2.3–2.7 mm, glabrous.


Phenology: Flowering Mar–Jun.
Habitat: Chaparral on slopes and in canyons
Elevation: 100–1200 m

Distribution

V6 758-distribution-map.jpg

Calif., Mexico (Baja California)

Discussion

Crocanthemum aldersonii occurs from Orange and San Bernardino counties south into Baja California. Although traditionally placed within a broadly circumscribed C. scoparium, the tall habit, paniculate inflorescence, and acuminate to acute inner sepals of C. aldersonii are more similar to those of C. suffrutescens. The calyx of C. aldersonii occasionally has stellate hairs with thickened bases, a characteristic always present in C. suffrutescens. The tall inflorescence, curved inflorescence branches, and relatively large corollas are unique among Pacific slope species of Crocanthemum.

Selected References

None.

Lower Taxa

None.

"broad" is not a number.

... more about "Crocanthemum aldersonii"
acute +  and acuminate +
Bruce A. Sorrie +
(Greene) Janchen in H. G. A. Engler et al. +
Helianthemum aldersonii +
2.1 cm21 mm <br />0.021 m <br /> (2.6 cm26 mm <br />0.026 m <br />) +
1 cm10 mm <br />0.01 m <br /> (2.1 cm21 mm <br />0.021 m <br />) +
scale-like +  and not lobed +
0.09 cm0.9 mm <br />9.0e-4 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
0.1 cm1 mm <br />0.001 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
0.03 cm0.3 mm <br />3.0e-4 m <br /> (0.05 cm0.5 mm <br />5.0e-4 m <br />) +
stellate-pannose +
stellate-pubescent +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.43 cm4.3 mm <br />0.0043 m <br />) +
0.23 cm2.3 mm <br />0.0023 m <br /> (0.27 cm2.7 mm <br />0.0027 m <br />) +
Alderson rushrose +
Calif. +  and Mexico (Baja California) +
100–1200 m +
connate +  and distinct +
chasmogamous +  and cleistogamous +
loculicidal +
Chaparral on slopes and in canyons +
0 cm0 mm <br />0 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
umbellate +, thyrsiform +  and cymose +
racemose +, paniculate +  and corymbose +
0.7 cm7 mm <br />0.007 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
0.47 cm4.7 mm <br />0.0047 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
0.2 cm2 mm <br />0.002 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
stipulate +  and estipulate +
whorled +, opposite +  and alternate +
undulate +  and revolute +
0.2 cm2 mm <br />0.002 m <br /> (0.28 cm2.8 mm <br />0.0028 m <br />) +
0.13 cm1.3 mm <br />0.0013 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
0.3 cm3 mm <br />0.003 m <br /> (?) +
6-12-carpellate +, 5-carpellate +, 3-carpellate +  and 2-carpellate +
crassinucellate +  and bitegmic +
orthotropous +
stellate-pubescent +
0.5 cm5 mm <br />0.005 m <br /> (1.3 cm13 mm <br />0.013 m <br />) +
crumpled +  and imbricate +
yellow +, white +, red +, purple +, pink +, dark red +  and green +
distinct +
8mm;12mm +
obovate +
0.6 cm6 mm <br />0.006 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
Flowering Mar–Jun. +
in H. G. A. Engler et al., Nat. Pflanzenfam. ed. +
persistent +
not dimorphic +
glabrate +  and sparsely stellate-pubescent +
30 cm300 mm <br />0.3 m <br /> (65 cm650 mm <br />0.65 m <br />) +
3 +  and 1 +
sessile +  and petiolate +
stellate-pannose +
H. scoparium var. aldersonii +
Crocanthemum aldersonii +
Crocanthemum +
species +