Rhyticaryum macrocarpum Becc.

Rio, Cédric Del, Stull, Gregory W. & Franceschi, Dario De, 2020, Survey of the fruits and endocarps of Icacinaceae (Lamiids, Icacinales), European Journal of Taxonomy 645, pp. 1-130 : 100

Rhyticaryum macrocarpum Becc.

Fig. 32.10–32.18

Material examined

Specimen used for endocarp and fruit description

NEW GUINEA • 1961; W. Vink 11381; L [ L.2293146 ].

PAPUA NEW GUINEA • 17 Feb. 1972; Katik 46856; L [ L.2293142] .

Description

FRUIT. Epicarp glabrous, mesocarp thick, leather-like in texture. Calyx not persistent. Length 35–43 mm, width 25–30 mm, thickness ca 15 mm.

ENDOCARP. Brown, length 28.8–36.3 mm, width 21.5–28.0 mm, thickness 13.7–14.6 mm. Keel surrounding the endocarp in the plane of symmetry. Apex slightly flattened, asymmetrical in lateral view; base rounded-truncate or cleft at the base, or slightly asymmetrical. Outer surface of the endocarp sparsely rugose and ridged, with ca 2–5 longitudinal ridges; the median ridge spanning from the base to the apex. Ridges rounded and large, enclosing ca 0–5 polygonal areoles, occasionally without transversal ridges. Endocarp possessing a symmetrical pair of pores positioned eccentrically and subapically on the median ridge. Primary vascular bundle positioned outside the endocarp wall. Endocarp wall 800– 950 µm thick excluding ridges (ca 1300 µm thick including ridges). Endocarp wall with three cell layers: outermost layer with ca 17 rows of anticlinally oriented cells, cells 16.4–47.7 µm in length, followed by a layer with ca 14 rows of periclinally oriented cells, cells 16.4–27.1 µm in width; innermost layer with one row of periclinally oriented cells, lining the locule surface with regularly spaced and large papillae; papillae 19.4–32.7 µm (av. 25.0 µm) in diameter, 400 papillae per 0.25 mm 2.