Adina Salisb.

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

Distribution

A small genus of 11 species distributed throughout Asia, from India to New Guinea (not reaching the Solomon Islands), and extending north to Japan; two species are in New Guinea: Adina multifolia Havil. and A. trichotoma (Zoll. & Moritzi) Benth. & Hook.f. ex B.D.Jacks. Previously placed in Pertusadina multifolia (Havil.) Ridsdale. and Metadina trichotoma (Zoll. & Moritzi) Bakh.f. respectively.

Morphology General Habit

Trees to 40 m, slightly buttressed or not, boles often fluted, grooved or latticed (A. multifolia); bark smooth, flaky or fissured; branches often lenticellate

Morphology General Buds

Terminal bud cone- or pyramid-shaped. Raphides absent

Morphology Leaves Stipules

Stipules c. 2–5 mm long, entire, caducous

Morphology Leaves

Leaves: petiole base ±articulated, midrib raised below, tapering off towards apex, main tertiary veins at ±90º to midrib becoming reticulate or loosely scalariform. Inflorescences terminal or terminal on lateral shoots or axillary, in groups of a few to >10 globular heads, overall arrangement compound-thyrsoid in appearance, reduced pair of bracteolate leaves and stipules present at joints, often reflexed then caducous

Morphology Reproductive morphology Flowers

Flowers 5-merous, free, aggregated around receptacle; calyx tube short, lobes persistent; corolla valvate, sub-imbricate at tip in bud, narrowly funnel- to salver-shaped; stamens adnate to upper part of tube, shortly exserted; style exserted; stigma spherical to club-shaped; ovary 2-locular, ovules pendulous, 4–12 per locule

Morphology Reproductive morphology Fruits

Fruits aggregated around common receptacle, fruitlets free, capsular, dehiscing from base upwards, valves detaching, ovary septum semi-persistent on receptacle

Morphology Reproductive morphology Seeds

Seeds angular, not winged to slightly winged.

Ecology

Adina trichotoma is widespread, and occurs in a variety of habitats including primary and secondary forests from rocky sea shores and near rivers to steep hillsides. Found on a variety of substrates including limestone and black soils from 0–1400 m.

Recognition

Adina multifolia is known only from the Bird’s Head Peninsula and nearby islands. Adina can be distinguished from other members of the Naucleeae tribe by the small stipules, small flower heads, reduced bracteolate leaves and stipules in the inflorescence (look distally for stipules before they fall, or for scars after they have fallen), articulated petioles, and the semi-persistent ovary septum giving the old infructescences a spiky appearance. Adina multifolia has fewer flowering heads than A. trichotoma and slightly winged seeds; the bole can be strongly latticed, resembling mature ‘strangling figs’ in some cases.