Hydnocarpus pentandrus (Buch.-Ham.) Oken

Hydnocarpus species are evergreen shrubs. Leaves simple, alternate, lanceolate-ovate to elliptic-oblong, base cuneate to obtuse, margin serrate to entire, apex acute to obtuse, pinnately veined, coriaceous, subcoriaceous to leathery, lateral veins upturned, gradually diminishing apically towards the margins, connected further with super adjacent secondaries by series of cross veins, dark green above, paler beneath, petiole usually thickened near the apex, stipules leaf like or foliaceous, caducous. Inflorescence in shortly pedunculate axillary racemes, branched cymes, fascicles, few flowered or sometimes solitary. Flowers unisexual (dioecious) or rarely monoecious or polygamous, hypogynous, pedicels articulate, bracts minute, caducous or sometimes persistent. Male flowers: Sepals 4-5, imbricate, subequal, free or slightly connate at the base, concave, caducous, petals 4-5, up to 16, connate at the base, fleshy pilose inside near the base. Stamens 5-100, filaments filiform, free, broadened at base, anthers 2 loculed, saggitate or reniform, basifixed, pollen fleshy, tricolporate, reticulate, subprolate to suboblate, rudimentary ovary densely pilose or absent. Female flowers: Solitary or in fascicles on short axillary pilose peduncles, usually from the older nodes, sepals and petals similar to male flowers but bigger, ovary superior, globose, carpels 4-5, connate, unilocular, ovules 2-few in 3,4,6 pariental placentae, stigma usually equaling the number of placentae, recurved, bifid deeply, apex dilated, pilose beneath, glabrous above. Fruit indehiscent berry, ovoid-globose, with thin coriaceous and fragile pericarp, or hard and thick. Seeds many, oblong-ovoid, slightly compressed, membranously arillate, oily endosperm, cotyledons foliaceous.

Hydnocarpus species are dioecious, i.e., male (staminate) flowers on one plant, and female (pistillate) flowers on another plant. Pollination is entomophilous i.e., by insects, or cleistogamy i.e., by self or allogamy i.e., by cross pollination. Flowering/Fruiting: February-September.

Seeds may be dispersed by autochory i.e., self dispersal, zoochory i.e., dispersal by birds or animals, anthropochory i.e., dispersal by humans.

Evergreen trees, about 5-25 m tall, diameter up to 3 m. Bark rough, brown, usually fluted, branchlets and shoots brownish pubescent. Leaves simple, alternate, variable, lanceolate-ovate, elliptic-ovate, oblanceolate to oblong, about 6-25 x 3.5-10 cm across, base usually inequilateral, cuneate to obtuse, margin entire or subserrate, apex abruptly or long acuminate, dark green above, paler beneath, lateral veins 5-8, on either side of the midrib, upturned, gradually diminishing apically towards the margins, impressed above and prominent beneath, minutely appressed pubescent on midrib and veins above when young, later glabrescent when mature, minutely pubescent beneath, connected further with super adjacent secondaries by series of cross veins, petiole usually swollen at both ends, brownish pubescent, about 7-15 mm long, stipules linear, minute, pubescent, caducous. Male flowers: greenish, in 2-3 raceme fascicles, densely brownish tomentose, about 6 mm long, peduncles about 1 cm long and pedicels about 7 mm long, both brown tomentose, sepals 4-5, imbricate, unequal, outer broadly ovate-orbicular, inner suborbicular, slightly connate at the base, concave, apex obtuse, densely brown ferruginous, about 2.5 mm across, petals 4-5, ovate-suborbicular, connate at the base, margins ciliate, pilose inside near the base, smaller than sepals. Stamens 5, filaments filiform, free, broadened at base, about 2 mm long, anthers 2 loculed, reniform, basifixed, pollen fleshy, tricolporate, ovary rudimentary densely pilose. Female flowers: Solitary or binate on short axillary pilose peduncles, about 8 mm long, usually from the older nodes, sepals and petals similar to male flowers but bigger, staminodes 5, linear-oblong, appressed to ovary apex obtuse, ovary superior, ovoid-ellipsoid, faintly penta angular, apex protruded, creamy yellow tomentose, carpels 5, connate, unilocular, stigma 5, usually equaling the number of placentae. Fruit indehiscent berry, obovoid-globose, about 5-10 cm across, reddish brown, pericarp hard, thick, tomentose. Seeds 15-20, oblong-ovoid, about 1.7-2.2 x 1-1.5 cm across, embedded in pulp, irregularly compressed, testa hard, oily endosperm, longitudinally striated.

Hydnocarpus species are susceptible to various insect pests, powdery mildews and moulds.

Evergreen, semi evergreen and along streams of moist deciduous forests, altitude 850 m.

Not evaluated (IUCN).

Cultivated in roadsides of hilly areas, timber used for building construction, oil used as medicine. Fruits used as fish poison.