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

Coussapoa
hairs are very common on young leaves, stipules,
inflorescences, etc. In dry material they
are more or less granular (powdery) in appearance.
4. Pearl bodies (or glands)-hyaline, succulent,
more or less club-shaped, and confined almost
entirely to the leaves. These trichomes
are found in specimens of Coussapoa microcarpa
and C. villosa cultivated in green houses.
Pearl bodies are probably common in the genus,
but are often not found in the field because
they are easily detached; moreover, they
are probably harvested by ants (cf. O'Dowd,
1982).
As with many other genera of the Cecropiaceae,
these four types of hairs are also often
encountered in Coussapoa species. Many species
have a dense or rather dense indumentum. In
several species arachnoid hairs are lacking and
most of these species have sparse indumentum
as well.
common in elliptic leaves, and in obovate leaves
normally there is none. Venation types in the
genus can be seen in Figure 1.
The ovate lamina with branched, basal, lateral
veins and a relatively long petiole can be regarded
as the least derived type of leaf in the genus,
as it shows the closest resemblance to leaves in
other genera of the family, especially Pourouma.
The leaves of P. minor resemble those of C. contorta
and the leaves of P. tomentosa and P. meliononii
are reminiscent of those of C. villosa and
C. nitida, respectively. The obovate, trinervate
lamina with a short petiole can be regarded as a
derived type of leaf. Another type of leaf, which
can also be regarded as derived, is that found in,
e.g., C. parvifolia and C. contorta. This type of
leaf has an elliptic to subovate lamina with many
unbranched lateral veins, a very regular venation,
and a relatively short petiole. These features
are characteristic more of the Moraceae than of
the Cecropiaceae.
The indumentum of the leaves also shows some
Leaves. -The petiole in most species is rela- variation in denseness and occurrence of differtively
long-up to half the length of the lamina. ent types of hairs. The occurrence of a dense and
There is a tendency towards shortening of the varying indumentum appears to be weakly corpetiole
(to one-tenth of the length of the lamina) related with primitiveness in other leaf characin
species with derived (i.e., obovate, trinerved) ters.
types of lamina. The relative length of the petiole C. contorta is distinct in having domatiumis
not subject to great variation as is the case in like cavities in the axils of the lateral veins.
related genera, such as Myrianthus and Pou- The stipules are connate, fully amplexicaul and
rouma.
caducous, usually leaving oblique scars, char-
The length of the lamina varies from more acteristic for the genus. The length varies conthan
50 cm to less than 10 cm and more or less siderably in the genus. One can roughly recognize
parallels the change in the shape of the lamina three categories: long stipules (5-15 cm long or
from cordiform, subreniform, or broadly ovate longer), medium-long stipules (1-5 cm long) and
to elliptic or oblong to obovate or subobovate; short stipules (less than 1 cm long). Long stipules
at the same time, this correlates with a gradation give protection for a longer time to young leaves
in the leaf base from cordate to truncate to and developing inflorescences, but a correlation
rounded to obtuse to subacute.
between the type of inflorescence or habit pref-
The venation is pinnate and brochidodromous erence and the length of the stipules is not apwith
a more or less regular parallel tertiary ve- parent.
nation in the intercostal area. The venation may Inflorescences. - Coussapoa, like all other gentend
toward subpalmate (C. vannifolia), or may era of the Cecropiaceae, is dioecious. Monoebe
more or less clearly trinervate (C. trinervia, cious specimens are rare.
C. cinnamomifolia), with this development being The inflorescences occur in pairs in the leaf
combined with a change towards a (sub)obvate axils, a feature common in the Cecropiaceae and
lamina. In ovate leaves the basal pair of lateral related families. The ramification of the inflovein
branches is mostly branched. Especially in rescence is basically similar to that usually found
large leaves, the other lateral veins show little in Myrianthus (see: De Ruiter, 1976) and Poubranching
(being mostly only furcate); however, rouma. The common peduncle bears at its apex
in C. asperifolia the other lateral veins are mostly (at least) three branches, a pattern repeated in
branched. Branching of the lateral veins is less secondary and further ramifications. However,
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