Atuna racemosa subsp. excelsa

Primary tabs

Atuna racemosa subsp. excelsa

Description

Tree to 45 m tall, the trunk buttressed up to 2 m, not fluted, the young branches sparsely strigose, flabrescent, obscurely lenticellate. Leaves rigidly chartaceous to coriaceous, ovate to oblong-ovate or less frequently oblong, 4.5-12 by 2-5 cm, acuminate at apex, the acumen 3-10 mm long, subcordate, rounded or subcuneate at base, glabrous on both surfaces; Stipules lanceolate, 8-15 mm long, acute, sparsely strigose, subpersistent. Inflorescences of axillary racemes to 7.5 cm long, or little branched with 2 or more racemose branches on short main peduncle, the rachis and branches densely short sericeous; Petals white to bluish white, oblong, to 5 mm long, caducous. Stamens 13-18, to 8 mm long with tooth-like stamin-odes opposite. Ovary pilose. Fruit subglobose to slightly pyriform, 5-7 cm diam. or 5-7 by 3.5-4.5 cm;

Distribution

Asia-Tropical: Borneo present; Jawa (Jawa present); Malaya (Peninsular Malaysia present); Sumatera (Sumatera present), Kedah present, N. Sulawesi present, Trengganu southward present
Malesia: Malay Peninsula (Kedah and Trengganu southward), Sumatra, Java, Borneo, N. Sulawesi. .

Notes

KOSTERMANS is probably correct in interpreting Petrocarya excelsa JACK as the species described here. The original description is quite detailed and fits this taxon better than any other Atuna.
KOSTERMANS treated these two subspecies as separate species. They were differentiated by small characteristics of leaf shape, the acumen and the base. While there do seem to be two elements involved in this complex, there is a complete graduation of any single character such as leaf length, apex length, petiole thickness, leaf shape or flower size. subsp. excelsa is much commoner in Sundaland and subsp. racemosa in the Sahul shelf and Pacific islands, but the two subspecies have considerable geographical overlap with subsp. racemosa occurring sporadically on the Malay Peninsula. Since all characters merge and are only weakly correlated, these two species are reduced to subspecies, a rank more in accord with their variational and geographical patterns.

Citation

HOOK. 1836 – In: Comp. Bot. Mag.: 220
Miq. 1855 – In: Fl. Ind. Bat.: 356
Hook.f. 1878 – In: Fl. Brit. India: 310
K. & V. 1900: Bijdr.: 337
JACK 1843 – In: Cale. J. Nat. Hist.: 164
Fl. Ind. Bat. 1861: Suppl. Sumatra: 307: descr.
Merr. 1923 – In: Enum. Philip. Fl. Pl.: 236
RIDLEY 1922 – In: Fl. Mal. Pen.: 669
PRANCE & WHITM. 1973 – In: Tree Fl. Malaya: 324
King 1897 – In: J. As. Soc. Beng.: 281
Hook.f. 1878 – In: Fl. Brit. India: 312
RIDLEY 1922 – In: Fl. Mal. Pen.: 669
C.MUELL. 1857 – In: Walp., Ann. 4: 644
RIDLEY 1922 – In: Fl. Mal. Pen.: 670
WALP. 1843 – In: Rep.: 7