Dysoxylum pettigrewianum
Description
Tree to 35 m and bole diam. 1.2 m; buttresses to 2.5 m tall and 2 m out.
Bark brown, smooth with conspicuous pustular lenticels to finely vertically cracked or flaking; underbark pink; sapwood pale straw; heartwood pinkish brown, hard.
Leaves to 80 cm, usually less, imparipinnate, 3–6-jugate, paler abaxially; petiole 6–10 cm, flattened and (in sicco) sometimes grooved adaxially, lenticellate, ± finely shortly pubescent, base swollen; rachis 2–3 mm diam., terete to grooved adaxially (in sicco), ± finely pubescent.
Flowers sessile, sweetly scented .
Petals 4, 8–9 mm long, linear-spatulate, acute, imbricate at least at apices, glabrous or adpressed puberulent at apices.
Staminal tube glabrous with 8 emarginate to bifid lobes; anthers 8, c. 1 mm long, oblong, subsessile, alternating with lobes, brown.
Ovary pubescent, 4-locular; style adpressed pubescent; stylehead discoid to subcapitate.
Fruits to 8 by 4 cm, conspicuously brown-lenticellate, glabrous, orange-brown, subspherical, stipitate and with milky latex when young then asymmetric if with aborted seeds, conspicuously 4-angled and conical at both ends when mature with white latex in pericarp.
Seeds 1–4, 23 by 14 mm, ellipsoid with orange sarcotesta.
Distribution
Aru Is. present, Asia-Tropical: New Guinea present, Australasia: Queensland (Queensland present), Bacan present, Halmahera present, New Britain present, Solomon Islands present
Malesia: Moluccas (Bacan, Halmahera, Aru Is.), New Guinea, New Britain, Solomon Islands, Australia (Queensland)
Taxonomy
This common tree, the scrub ironbark or Cairns satinwood of Australia, is closely related to Dysoxylum brevipaniculum though that is a small tree with very short inflorescences. The fruit and habit serve to distinguish it from D. cumingianum, its vicariant.
Very closely allied to Dysoxylum pettigrewianum or, possibly, a robust pubescent form of it are a number of gatherings from lowland New Guinea. The specimens of D. pettigmwianum with large leaflets are very similar but lack the heavy pubescence on the adaxial surface of the veins and the abaxial leaflet surfaces. However, flowers are unknown to me. The form has been collected from a number of localities in both NW and NE New Guinea.