Parartocarpus Baill.

Timothy M. A. Utteridge and Laura V. S. Jennings (2022). Trees of New Guinea. Kew Publishing. Royal Botanic Gardens, Kew

Morphology General Habit

Trees to 35 m tall

Morphology Leaves Stipules

Stipules interpetiolar, semi-amplexicaul, fused

Morphology Twigs

Twigs and lamina whitish to brown puberulous (in New Guinea)

Morphology Leaves

Leaves spirally arranged, margin entire and often revolute, tertiary venation reticulate to scalariform

Morphology Reproductive morphology Inflorescences

Inflorescences unisexual, rarely bisexual and plants usually dioecious, solitary, axillary, subglobose to capitate, subtended by 3–8 large involucral bracts

Morphology Reproductive morphology Flowers

Flowers fully connate; male flowers with 1–3 stamens, filaments partly fused; female flowers rounded to conical or apiculate at the apex, ovary free, stigma 1. Infructescences lobed or folded, surface firm, with conical, apiculate or discoid processes up to 1 cm long, numerous stony endocarps embedded in a fleshy mid-layer.

Distribution

In New Guinea, Parartocarpus occurs in lowland evergreen forest up to 1000 m. A genus of two species, distributed from Thailand to the Solomon Islands; one species in New Guinea and the Solomon Islands: Parartocarpus venenosus (Zoll. & Moritzi) Becc.

Recognition

The genus can be distinguished by the leaves with entire margins, the fused interpetiolar stipules, the presence of bracts at the base of the inflorescences, the infructescence with a firm outer layer with spiny processes and a fleshy inner layer that contains the stony endocarps. In fruit, Parartocarpus may resemble Artocarpus, but in Parartocarpus the fruit has an infolded or slightly lobed surface, whereas Artocarpus has a uniform surface.