Malacothamnus aboriginum

(B. L. Robinson) Greene

Leafl. Bot. Observ. Crit. 1: 208. 1906.

Common names: Indian Valley bushmallow
Endemic
Basionym: Malvastrum aboriginum B. L. Robinson in A. Gray et al., Syn. Fl. N. Amer. 1(1,2): 311. 1897
Synonyms: Sphaeralcea aboriginum (B. L. Robinson) Jepson
Treatment appears in FNA Volume 6. Treatment on page 285. Mentioned on page 280, 281.

Subshrubs or shrubs, 2–3 m, branches ± stout, indument grayish to tawny, shaggy-tomentose, stellate hairs sessile or stalked, many-armed. Leaf-blades ovate, broadly ovate, or round, 3-lobed or 5-lobed, 4–7 (–12) cm, thin or thick, surfaces: sparsely to densely grayish to tawny-short-stellate-hairy, basal sinus open, not overlapping. Inflorescences interrupted, spicate or racemose, flower clusters sessile or subsessile, subtended by conspicuous bracts, usually densely flowered, usually 10 flowers per node; involucellar bractlets distinct or basally connate, subcordate, narrow-elliptic, or ± round, 6–15 × (1–) 3–9 mm, 2/3 to exceeding calyx length. Flowers: calyx strongly plicate, angled or winged in bud, 8–17 mm, lobes subcordate, ovate, or ± round, 5–11 × 3.5–10 mm, slightly longer than broad, ca. 2 times tube length, apex abruptly acuminate, stellate-hairy, hairs many-armed; petals pale-pink to rose, 1–2 cm. Mericarps 2.5–3.5 mm. 2n = 34.


Phenology: Flowering Apr–Jun, Aug–Oct.
Habitat: Chaparral
Elevation: 100–800(–1700) m

Discussion

Malacothamnus aboriginum occurs principally in the central inner Coast Ranges and in the Laguna Mountains in San Diego County. There, plants have involucellar bractlets about 1 mm wide but otherwise appear to be M. aboriginum; these have sometimes been assigned to M. densiflorus. The character of the often connate, wide involucellar bractlets is distinctive of M. aboriginum.

Selected References

None.

Lower Taxa

None.
... more about "Malacothamnus aboriginum"
loculicidal +
stellate-hairy +
acuminate +
David M. Bates +
(B. L. Robinson) Greene +
not overlapping +
cordate +  and truncate or cuneate +
Malvastrum aboriginum +
7 cm70 mm <br />0.07 m <br /> (12 cm120 mm <br />0.12 m <br />) +
4 cm40 mm <br />0.04 m <br /> (7 cm70 mm <br />0.07 m <br />) +
5-lobed;3-lobed;round;ovate;5-lobed;3-lobed;round;ovate;5-lobed;3-lobed;round;ovate;ovate +
thick +  and thin +
asymmetric +  and symmetric +
ovate +  and round rhombic or reniform unlobed or palmately 3-lobed 5-lobed or 7-lobed +
conspicuous +
0.1 cm1 mm <br />0.001 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
connate +  and distinct +
0.6 cm6 mm <br />0.006 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
round +, narrow-elliptic +  and subcordate +
0.3 cm3 mm <br />0.003 m <br /> (0.9 cm9 mm <br />0.009 m <br />) +
not accrescent +
0.8 cm8 mm <br />0.008 m <br /> (1.7 cm17 mm <br />0.017 m <br />) +
indehiscent +  and loculicidal +
Indian Valley bushmallow +
white +, usually rose +  and pale-pink pinkish mauve or mauve +
campanulate +  and subrotate +
100–800(–1700) m +
sparse;copious +
subterminal +
flowered +, subsessile +, sessile +  and clusters +
unisexual +  and bisexual +
subglobose-obovate +, disclike +  and not inflated +
Chaparral +
many-armed +, stalked +  and sessile +
bifurcate +
spicate +  and interrupted +
tough-fibrous +
connate +  and distinct +
simple +, stipulate +, sessile +, subsessile +  and petiolate +
distichous +  and alternate +
slightly longer than broad +
round +, ovate +  and subcordate +
0.35 cm3.5 mm <br />0.0035 m <br /> (1 cm10 mm <br />0.01 m <br />) +
entire +  and serrate +
smooth-walled +  and 1-celled +
asymmetrically suborbicular +  and obovoid-reniform +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
7-14-carpellate +
pale-pink;rose +
adnate +  and distinct +
1 cm10 mm <br />0.01 m <br /> (2 cm20 mm <br />0.02 m <br />) +
Flowering Apr–Jun, Aug–Oct. +
Leafl. Bot. Observ. Crit. +
minutely stellate-hairy or rarely glabrous +  and papillate-stellate +
black +  and brown +
hairy +  and glabrous +
obovoid-reniform +
persistent +
sessile +  and subsessile +
ascending;erect +
filiform +, linear +  and capitate +
1-2 times number of carpels +
filiform +  and subulate +
7-14-branched +
tawny-short-stellate-hairy +
Sphaeralcea aboriginum +
Malacothamnus aboriginum +
Malacothamnus +
species +
shrub +  and subshrub +
glabrate +  and densely hairy +
monoecious +, dioecious +  and hermaphroditic +