The type of S. ramiflora, collected by Poeppig on Rio Huallaga in southwestern
Loreto, Peru, was in young fruit. We have compared a photograph of the Berlin
sheet (apparently only fragments from that at Vienna, now lost) and a leaf from it
(F) with all relevant Amazonian material now available and found an extremely close
match in one staminate flowering specimen from Sierra de la Macarena, Meta, Colombia (Philipson, Idrobo & Jaramillo 2191, COL), which we propose to take as a standard of comparison for the male sex, the sex that in Sciadotenia can be
expected to express most of the practical differential characters. Proceeding from
this identification we find that the staminate inflorescence described as that of S.
ramiflora in the revision (Brittonia 3: 29) was incorrectly assigned, that of genuine
S. ramiflora being narrowly spiciform and essentially unbranched, whereas the
filiformly branching inflorescence thought to be that of S. ramiflora is actually that
of S. amazonica. Study of the individual staminate flowers brings out further differences
in number and of the sepals and in size of petals, summarized in our key above,
and provides additional evidence that there really are two related but distinct species
corresponding with S. ramiflora and S. amazonica, although the original descriptions,
based on fruiting specimens, one of them incomplete, could not provide any firm
differential characters. The differences in leaf-outline, once thought important,
are now recognized as valueless, a point clearly demonstrated by the plant from
Sierra de la Macarena just mentioned, in which the leaves vary in outline from
narrowly oblong-elliptic truncate at base to ovate-oblong-elUptic subcordate at base.
See further under S. amazonica, below.
In the isthmus region of Panama and adjoining Colombia this group of the genus
is represented by an obviously related entity with shorter, more richly branched
inflorescences bearing flowers that differ substantially in features of petal and
androecium. First described as Odontocarya nitida Riley, a name which we listed
[:Mem. N. Y. Bot. Gard. 20(2): 76] as a synonym of S. ramiflora, it now appears
adequately distinct and reasonably treated as an independent species.
It may be worth noting that the epithet ramiflora, which suggests a branched
staminate inflorescence, refers, on the contrary, to six-armed carpophores issuing
from the solitary terminal pistillate flower.