Pyrenacantha ambrensis Labat, El-Achkar & R.Rabev.

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 : 71-72

Pyrenacantha ambrensis Labat, El-Achkar & R.Rabev.

Fig. 23.19–23.27

Material examined

Specimen used for endocarp and fruit description

MADAGASCAR • 1993; O. Andrianantoanina & A. Solotiana 62; P [ MNHN-P-P00440603 ].

Description

FRUIT. Elliptical to globose, accrescent at the apex, brown-orange when mature. Epicarp puberulent with yellow small ovoid hairs with an acuminate apex and simple hairs with granular ornamentation, shriveled when dry. Mesocarp 480–500 µm thick when dry. Calyx persistent, separated from the fruit by an extended gynophore. Length 25–30 mm, width 19–22 mm, thickness 15.0– 16.6 mm.

ENDOCARP. Brown, elliptical to globose in lateral view, globose in transverse section, length ca 22.5 mm, width ca 17 mm, thickness ca 15 mm. Trace of keel present in the upper part. Apex with acute protuberance, asymmetrical in lateral view; base rounded, symmetrical. Outer surface of the endocarp pitted. Pits circular, occasionally elongated longitudinally, 0.4–1.4 mm in length, randomly arranged with 11–12 pits longitudinally and 12–15 pits transversally (ca 145–150 pits per face). Pits associated with spiny tubercles protruding into the locule; tubercles ca 3–4 mm in length and 647–931 µm in diameter at the base, faintly capitate at the apex, with 26–27 cells in width. Tubercle cells sclerotic, digitate and elongate. Endocarp wall 569–601 µm thick (excluding pits). Endocarp wall (excluding pits) with three cell layers: outermost layer with 8–14 rows of anticlinally oriented cells, cells 17.8–50.5 µm in length, followed by a layer with 3–9 rows of periclinally oriented cells, cells 17.7–23.7 µm in width; innermost layer with one row of periclinally oriented cells, cells 0.5–1.4 µm in width, lining the locule surface with regularly spaced and sessile rounded papillae; papillae 7.6–13.1 µm (av. 10.6 µm) in diameter, with ca 1000 papillae per 0.25 mm 2. Locule surface not lacunate.

Remarks

The innermost row of periclinally oriented cells, which have a small width, could be collapsed due to a dryness inside the locule.