Ageratum maritimum

Kunth in A. von Humboldt et al.

in A. von Humboldt et al., Nov. Gen. Sp. 4(fol.): 117. 1818.

,

4(qto.) 150. 1820.

Common names: Cape Sable whiteweed
Synonyms: Ageratum littorale A. Gray Ageratum littorale var. hondurense B. L. Robinson
Treatment appears in FNA Volume 21. Treatment on page 482. Mentioned on page 481.

Annuals or perennials, 10–50 cm (semisucculent, rhizomatous, forming colonies). Stems decumbent to straggling or creeping (rooting at nodes), glabrous but for puberulous-pilose nodes. Leaf-blades deltate-ovate to oblong, mostly 0.8–4 × 0.5–3 cm, (fleshy) margins toothed, faces glabrous or glabrate. Peduncles glabrous or glabrate. Involucres ca. 3 × 3–4 mm. Phyllaries elliptic-lanceolate, glabrous or glabrate, tips abruptly tapered to nearly obtuse. Corollas lavender or blue to white. Cypselae glabrous; pappi usually blunt coronas ca. 0.1 mm, rarely of separate scales.


Phenology: Flowering year round.
Habitat: Beach sand and nearby thickets, coral soils, salt marshes, hammocks, roadsides
Elevation: 0–10 m

Distribution

V21-1210-distribution-map.gif

Fla., Mexico (Quintana Roo), West Indies (Cuba), West Indies (Hispaniola), Central America (Belize)

Discussion

Plants from Florida (Ageratum littorale, the type from Florida) are described here. Plants of the West Indies and Mexico (broadening the species concept to A. maritimum, the type from Cuba) have various elaborations of vestiture and a more conspicuous pappus–coronas with even to laciniate margins or rings of nearly separate scales mostly 0.2–1.5 mm. In addition to the distinctive relatively small, glabrous or glabrate leaves, plants of A. maritimum are characterized by heads in clusters, usually held well beyond the leaves.

Selected References

None.

Lower Taxa

None.

"fine" is not a number.

... more about "Ageratum maritimum"
not tailed +, truncate +, rounded +  and obtuse +
scarious +
usually ovate +  and lanceolate +
usually terete +  and clavate +
spiciform +, racemiform +, paniculiform +  and corymbiform +
indeterminate +  and determinate +
Guy L. Nesom +
Kunth in A. von Humboldt et al. +
decurrent +
not enlarged +
dissected +, lobed +, toothed +  and entire +
deltate;ovate or elliptic +
papillate +  and rugose +
(4-)5-angled;10-ribbed +
less linear;clavate +
Cape Sable whiteweed +
blue +  and white +
0.1 cm1 mm <br />0.001 m <br /> (?) +
prismatic +
fertile +  and bisexual +
Fla. +, Mexico (Quintana Roo) +, West Indies (Cuba) +, West Indies (Hispaniola) +  and Central America (Belize) +
0–10 m +
glabrate +  and glabrous +
pistillate +, staminate +  and neuter +
winged +  and beaked +
dispersed +
Beach sand and nearby thickets, coral soils, salt marshes, hammocks, roadsides +
cymiform +  and corymbiform +
in usually determinate , rarely indeterminate , arrays +  and singly +
indeterminate +
each +  and sessile +
3 cm30 mm <br />0.03 m <br /> (?) +
campanulate +
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 /> (0.4 cm4 mm <br />0.004 m <br />) +
0.8 cm8 mm <br />0.008 m <br /> (4 cm40 mm <br />0.04 m <br />) +
0.5 cm5 mm <br />0.005 m <br /> (3 cm30 mm <br />0.03 m <br />) +
lanceolate +  and lance-linear +
puberulous-pilose +
2-carpellate +
persistent +
coroniform +
glabrate +  and glabrous +
Flowering year round. +
glabrate +  and glabrous +
30 +  and 40 +
subequal +  and unequal +
in A. von Humboldt et al., Nov. Gen. Sp. +
1818 +  and 1820 +
bearing subulate enations +, hairy +  and bristly +
5 +  and 6 +
aristate +
exalbuminous +
creeping +, decumbent +  and straggling +
prostrate +  and ascending +
appendaged +  and truncate +
hirsutulous +
papillate +
Ageratum littorale +  and Ageratum littorale var. hondurense +
Ageratum maritimum +
Ageratum +
species +
campanulate +
abruptly tapered +  and nearly obtuse +
perennial +  and annual +
10 cm100 mm <br />0.1 m <br /> (50 cm500 mm <br />0.5 m <br />) +
vine +, shrub +  and subshrub +