A new variety of Sarcotheca Laxa (Oxalidaceae) from Sumatra

In 1985 during the Fourth Expedition to S Aceh, Sumatra, in the neighbourhood of the G. Leuser National Park a representative of Sarcotheca (Oxalidaceae) was collected. It clearly is a member of the S. laxa complex previously known only from Malaya and the Riouw Archipelago. It differs from all by the golden puberulous, soon glabrescent innovations, the thicker, broader, more ovate leaflets, and the structure of the inflorescences (short, slender, subequally branched). In the technical characters it seems closest to var. sericea (Ridley) Veldk., but it differs by the leafblades with fewer pairs of nerves, the sparsely white puberulous inflorescence axes and branches (the hairs can easily be distinguished separately and seem longer), the pedicels with the lower part distinctly much longer than the upper, the rounded petals, and the apparently larger fruits. It does not seem to be identical with the collection from the Riouw Archipelago mentioned earlier [Veldkamp, Blumea 15 (1967) 533; Fl. Males. I, 7 (1971) 171], which has the typical long and narrow leaves of the other varieties of S. laxa, although also rather coriaceous. The infructescence seems similar, but the sepals in fruit are hairy mainly in the midline and not regularly all over as in var. brigittae. Another collection from the same area is De Wilde & De Wilde-Duyfjes 20674 (L).