Flora of Dominica, Part 2 - Smithsonian Institution Libraries

NUMBER 77 ASTERACEAE 41
Eupltorium celtidifoliwn Lamarck, 1788,2:406.--Domin, 193Od:M.
Eupltoriwn plkatwn Urban, 1907,5:523.
Sprawling glabrescent subshrubs; leaves opposite, shortly
petiolate, 3-veined but often with a pair of veins below,
conspicuously (with magnification) dark gland-dotted beneath,
margins distantly sermlate, apex long-tapered, base obtuse to
rounded; inflorescence loose; heads small, 7-20-flowered;
involucral bracts 7-16, in 1-2 series; receptacle slightly
convex, naked; anther appendages wider than long, very short;
style base unenlarged, stylar appendages distinctly enlarged
apically, smooth; achenes 5-ribbed, ribs setiferous, wpopodium
short and narrowed below; pappus of many capillary
bristles, 2-3 mm long.
Northern South America into Antilles; occasional weed in
Dominica, apparently in f drier sites: Clarke Hall (Ernst 1262,
Stern & Wasshausen 2398), Petit Coulibri (Whitefoord 4665,
a)02), Riviere Douce (Eggers 68), Rosehill (Eggers 541),
South Chiltem (Ernst 1876), Soufriere (Lloyd 737).
Luctuca Linnaeus
(by K. Chambers)
Lactuca sativa
Lactuca sativa haeus. 1753:795.-Adjanohoun et al., 1985:83, pl. 50.
Lettuce.
Glabrous annual herb with milky sap; leaves alternate, upper
ovate to orbicular, lower variable, apiculate-sermlate, auriculate-clasping;
inflorescence a large panicle, branchlets with
numerous clasping bracts; involucre of several series; receptacle
flat, naked; florets yellow, all ligulate and 5-toothed;
achenes oblanceolate, flattened, with a slender beak to apex,
pappus of silky bristles.
Widely cultivated plant; new record for Dominica (perhaps
escaping): Clarke Hall (Chambers s.n.).
Melanthera Rohr
Views on typification of the generic name were summarized
by Nicolson (1981a:491), arguing that the generic name should
rest on a Rohr collection (at C) from Martinique that has been
variously identified as M. nivea (Linnaeus) Small, M. panduriform‘s
Cassini and M. aspera var. glabriuscula (Kuntze) Parks,
not on the type of a species name. This is contrary to Art. 10
(ZCBN), which says a generic name is typified on the type of a
species name.
Melanthera aspera
Melanthera aspera (Jacquin) Steudel ex Small, 1909:164.-Fawcett in Fawcett
& Rendle, 1936,7(5):232.-Parks, 1973: 190.
Calea aspera Jacquin, 1788, Coll., 2:290, 1789, Icon., 3:13, pl. 583.
Melonthera deltoidea Michaux, 1803. 2:107, “Melananthero,” nom. illeg.
[incl. type of Calea aspera Jacquin].-Grisebach, 1861 :372.
Herb; leaves opposite, dentate; capitula mostly solitary on
peduncles to 10 cm long; involucral bracts in 2-3 series;
receptacle convex, pales shortly aristate; corollas tubular;
achenes 4-angled, with 2-4 caducous bristles.
Weed of Caribbean and northern South America; apparently
rarely collected on Dominica: Marigot (Hodge 774).
The binomial is attributed to Steudel (1841, 2:113), but he
didn’t accept the name, treating “M. aspera Rich.” as a
synonym of M. deltoidea Michaux. The binomial also appears
(attributed to L. Richard) in Sprengel(1821,2:135; 1822,3:40)
apparently as a nomen nudum.
Our material presumably falls in Melanthera aspera Steudel
ex Small var. glabriuscula (Kuntze) Parks. At least one recent
worker, Nash (in Standley and Steyermark, 1976,12:264), feels
that M. aspera is conspecific with Melanthera nivea (Linnaeus)
Small. Domin (193Od:77) reported Imray 162 (K) from
Dominica as M. nivea.
Mikania Willdenow, nom. cons.
A widespread species, Mikania cordifolia (Linnaeus f.)
Willdenow, has been reported for Dominica by VBlez
(1957:81) but no specimens have been seen. Medicinal usage
for that species was reported by Adjanohoun et al. (1985:85, pl.
52). Specimens from Guadeloupe (Stehle 5466, Duss 2814) and
Martinique (Duss 310) have been seen, the latter misidentified
and cited by Urban as M. scandens (= M. micrantha here). It
usually has cordate leaves with toothed margins of M.
micrantha but is densely pubescent and has distinctly longer
involucres (6-8 mm) and achenes (3-4 mm).
1. Leaves thick-coriacous; heads small (involucre 2 mm
long); plants of summits of high mountains . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . M. ovalis
1. Leaves thin-coriaceous to membranous: heads larger
(involucre 4-8 mm long); plants of middle to lower
elevations.
2. Inflorescences ending in pedicelled heads: leaves membranous,
usually cordate at base with toothed margins
. . . . . . . . . . . , . . . . . . . . , . M. micrantha
2. Inflorescences ending in 3 sessile heads; leaves thincoriaceous,
usually rounded at base with entire margins.
3. Heads smaller (involucre 4-5 mm); achenes shorter
(2-3 mm) . . . . . , . . . . . . . . M. hookeriana
3. Heads larger (involucre 6-7 mm); achenes longer
(4-5 mm) . . . . . . . . . . . . . . . . M. iiatifolia
Mikania hookeriana
Mikania hookeriaw A.P. Candolle, 1836,5:195.
Mikanicr badieri A.P. Candolle, 1836, 5:194.-Urban, 1907, 5:219.--DOmin,
193Od:67.--Stehl6, 1954b371.
Mikania hap^ Grisebach, 1861:363.
Mikania hookriano var. badieri (A.P. Candolle) Robinson, 1934x51.
Herbaceous, twining vines; leaves opposite, thinly coriaceous,
base rounded, margins entire; heads C sessile; involucre