Viola sumatrana
Content
Description
Perennial;
Leaves ¾-7 by ¾-4 cm, 1-1¾ times as long as broad, ovate, moderately to deeply cordate at base, acute, serrate, glabrous or rarely with scattered hairs below, especially on veins, dark green or purplish above, glaucous below;
Stipules 6-14 by 1-3 mm, linear-lanceolate, long-acute, long-fimbriate, fuscous.
Flowers 10-14½ mm, purple to creamy white, with darker veins;
Sepals 5-7 by c. 1 mm, linear-lanceolate, acute, entire, glabrous or sparsely pubescent, rarely ciliate;
Petals 2-4 times as long as broad;
Capsule 7-11 mm, ellipsoid, glabrous.
Distribution
Asia-Temperate, Asia-Tropical: Borneo present (Sabah present, Sarawak present); Malaya (Peninsular Malaysia present); Sumatera (Sumatera present); Thailand (Thailand present), Batu Tibang present, Burma present, Mt Kinabalu present
China, Burma, Thailand, Indo-China, in Malesia: Sumatra, Malay Peninsula, Borneo (Sarawak: Batu Tibang; North Borneo: Mt Kinabalu). .
Notes
This species has close affinities with V. pilosa and V. curvistylis. It differs from V. pilosa in the marginate stigma, unbearded lateral petals, short rounded calycine appendages, entire and usually glabrous sepals, and the generally glabrous leaves which are usually much darker on the upper side and which have glandular-serrate margins. V. curvistylis differs in its leaf-shape, bearded lateral petals, frequently hirsute sepals and its pale green, usually pilose leaves. V. sumatrana is apparently sympatric with V. curvistylis in the Malay Peninsula (Pahang), North Borneo (Mt Kinabalu) and Sumatra (Mt Kerintji), and with V. pilosa in Sumatra (Mt Kerintji).
The type description gives flower colour as yellowish, hence the recognition of var. caerulescens by BOISSIEU & CAPITAINE to account for their purple-flowered specimens. Plants with yellowish or whitish flowers have been encountered sporadically throughout the range of the species, sometimes with the typical purple-flowered form. These specimens cannot otherwise be distinguished from the rest of the material examined and are undoubtedly colour mutants which do not merit formal taxonomic recognition.
The type description gives flower colour as yellowish, hence the recognition of var. caerulescens by BOISSIEU & CAPITAINE to account for their purple-flowered specimens. Plants with yellowish or whitish flowers have been encountered sporadically throughout the range of the species, sometimes with the typical purple-flowered form. These specimens cannot otherwise be distinguished from the rest of the material examined and are undoubtedly colour mutants which do not merit formal taxonomic recognition.