Survey of the fruits and endocarps of Icacinaceae (Lamiids, Icacinales)
Author
Rio, Cédric Del
Author
Stull, Gregory W.
Author
Franceschi, Dario De
text
European Journal of Taxonomy
2020
2020-05-14
645
1
130
journal article
22093
10.5852/ejt.2020.645
1cd473d9-9d96-438f-bab4-29c5e56f82b8
3829651
Rhyticaryum racemosum
Becc.
Fig. 33.10–33.18
Material examined
Specimen used for endocarp and fruit description
NEW GUINEA
• 1954;
Royen
344
8;
L
[
L.2293115
].
Description
FRUIT. Epicarp glabrous; mesocarp
70–200 µm
thick when dry. Length
15–18 mm
, width 10.0–
13.8 mm
, thickness
8–10 mm
.
ENDOCARP. Cream, length ca
17.1 mm
, width ca
13.3 mm
, thickness ca
10 mm
. Keel surrounding the endocarp in the plane of symmetry. Apex asymmetrical in lateral view; base rounded, symmetrical. Outer surface of the endocarp ridged, with three longitudinal ridges; the median ridge spanning from the base to the apex. Ridges sharp and thin, with a median channel, delimiting a reticulate pattern enclosing ca 10 irregular areoles, each with freely ending ridgelets more or less branched. Endocarp primary vascular bundle outside the endocarp wall. Endocarp wall
363–391 µm
thick excluding ridges (
520–686 µm
thick including ridges). Endocarp wall with three cell layers: outermost layer with ca 8 rows of anticlinally oriented to isodiametric cells, cells
15.7–28.7 µm
in length, followed by a layer with ca 11 rows of periclinally oriented cells, cells 8.1–20.0 µm in width; innermost layer with one row of periclinally oriented cells, cells
5.9–7.4 µm
in width, lining the locule surface with regularly spaced and large papillae; papillae 8.0–27.0 µm (av.
16.4 µm
) in diameter, ca 790 papillae per
0.25 mm
2
.