Cecropiaceae: Coussapoa and Pourouma, with an ... - CNCFlora

Introduction
are more closely related to the Urticaceae than attached, entire, palmately-incised, or peltate and
to the Moraceae. Poikilospermum shows more radially-incised; venation pinnate, (sub)palmate,
urticaceous features, including the typical urti- trinervate, or radial; stipules fully amplexicaul
caceous cystoliths, than the other five genera (cf. and connate. Inflorescences in the leaf axils, usu-
Berg, 1989c; Bonsen & ter Welle, 1983). All gen- ally in pairs, unisexual, branched, with the flowera
match the Urticaceae in the (sub)basal at- ers ? solitary or clustered in heads or spikes, or
tachment of the ovule and the absence of milky unbranched with a single head or spike, bracteate
sap. They are, however, clearly different from or ebracteate. Staminate flowers with 2-4 free or
the Urticaceae in the absence of urticaceous (i.e., connate tepals; stamens 1-4; pistillode absent.
explosive) stamens. Such stamens are inflexed in Pistillate flowers with 2-4 connate tepals; pistil
the bud and, at anthesis, bend suddenly and one, ovary free from the perianth, unilocular;
elastically outward, throwing out the pollen. The ovule one, (sub)basally attached; stigma one,
African and Neotropical genera have a truly penicillate to peltate. Fruit an achene or somewoody
habit (cf. Bonsen & ter Welle, 1983). Oth- times (in Coussapoa) ? drupaceous, enveloped
er features which characterize the family are strict by a ? fleshy perianth; seed small, with endodioecy,
watery sap that turns black after exposure sperm, or large and without endosperm; embryo
to the air, the common occurrence of palmately- straight, cotyledons equal and flat or thickened.
incised leaves and, in certain species, radially- A pantropical family with six genera and apincised,
peltate leaves, large stipules (connected proximately 180 species.
with the protection of young inflorescences), and
adventitious aerial roots. While these roots are
manifest as stilt-roots in most genera, in Cous- Key to the Neotropical Genera
sapoa they are associated with the hemi-epi- 1. Lamina peltate, radially-incised. ...... Cecropia.
phytic habit and in Poikilospermum with the 1. Lamina basally attached, entire or palmately-inclimbing
habit.
cised.
The inflorescences of the 2. Staminate flowers with 1 or with 2 or 3 con-
Cecropiaceae vary nate
from being branched, with a + loose
stamens; pistillate flowers sessile, in gloarrange-
bose (to ellipsoid) heads; fruits small; stipule
ment of the flowers (as in some staminate inflo- scars usually ascending. .......... Coussapoa.
rescences of Pourouma), to unbranched, with a 2. Staminate flowers with 2-4 free stamens (or,
single globose flower head (as in some pistillate
in P. napoensis, 3-4 connate stamens); pistilinflorescences
of Coussapoa), to a subumbellate
late flowers pedicellate (to subsessile), solitary
or in non-capitate clusters; fruits
inflorescence (as in
large; stipule
Pourouma minor), or clusters scars horizontal. ................ Pourouma.
of spikes enveloped by a spathe (as in most Cecropia
species).
In all Cecropiaceae the fruits are enveloped by
a ? fleshy perianth, and with regard to pollination
and dispersal, the Cecropiaceae are more
similar to the Moraceae than to the Urticaceae.
The genus Cecropia shows the most derived
characters in the family, not only with regard to
leaves and inflorescences, but also in the features
connected with the adaptation to a mutualistic
relation with ants, as well as in the peculiar detachment
(abscission) of the anthers (cf. Berg,
1977b).
Cecropia Loefling, Iter Hispan. 272. 1758, nom.
conserv. Type. C. peltata Linnaeus.
Trees, terrestrial, usually with stilt-roots; internodes
usually hollow. Lamina peltate, radially
incised, venation radial, petiole mostly with
1-2 trichilia (patches of dense indument, usually
with trichomes forming Miillerian bodies) at the
base. Inflorescences digitate clusters of spikes (or
a single spike), usually enveloped by a spathe
until anthesis, interfloral bracts absent. Perianth
tubular; stamens two; stigma penicillate to peltate.
Fruit small, dry, enveloped by a greenish
Description of the Family
Cecropiaceae
Trees or shrubs, terrestrial or hemi-epiphytic,
with aerial roots, and watery sap turning black
upon exposure. Leaves in spirals; lamina basally
fruiting perianth.
With approximately 80 species throughout the
Neotropics, with a distinct concentration of
species in the Andean region.
Revisions of Coussapoa and Pourouma are
presented sequentially below.
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