A NEW SPECIES OF TUPISTRA ( CONVALLARIACEAE ) FROM SUMATRA

The genus Tupistra Ker Gawl. (s.str.) is a relatively small genus, comprising about 13 species, and distributed mainly in South and Southeast Asia, including Nepal, Bhutan, India, Myanmar, China, Laos, Vietnam, Thailand and Malaysia. In the course of revising the genus, a new, very distinct species was found in the material from northern Sumatra, Indonesia. This species is described, illustrated and diagnostically compared with some related ones.


INTRODUCTION
The genus Tupistra Ker Gawl.(s.str.) is a relatively small genus, comprising about 13 species, and distributed mainly in South and Southeast Asia, including Nepal, Bhutan, India, Myanmar, China, Laos, Vietnam, Thailand and Malaysia.

Tupistra sumatrensis
Notes -In general appearance, this new species resembles Tupistra grandis Ridl.described from the Malay Peninsula (Ridley, 1900), but differs clearly from it by the dark violet, capitate, irregularly ramulose stigma (Fig. 2), and by the other diagnostic characters stated above (Fig. 1, 2).In contrast to T. sumatrensis, T. grandis has white, orbicular, thin, spreading stigmas with crenulate margins, anthers located in the middle of the perianth tube, shorter perianths (to 14 mm long) with lobes shorter than the tube, shorter pistils (to 14 mm long) and shorter spikes (to 24.5 cm long).
The genus Tupistra in the Malesian region was reviewed by Jessop (1979).He recognised two species, T. violacea Ridl.and T. grandis, from there.It is apparent that T. sumatrensis is included in his circumscription of T. grandis, judging from his account.For instance, figures 14b and 14c of his article (Jessop, 1979) depict the flowers of T. sumatrensis, while figure 14a illustrates the habit of T. grandis.The holotype and two other specimens (Galoengi 91 and Lörzing 6284, listed below) of T. sumatrensis were formerly annotated on the label as T. violacea by Lörzing (Lörzing 6284 is also given the same annotation by Van Steenis).But T. violacea (Ridley, 1904) differs from T. sumatrensis mainly by its anthers located in the middle of the perianth tube, shortly club-shaped or turbinate, unramulose stigmas, shorter perianths (to c. 16 mm long), shorter pistils (to 11 mm long) and shorter reclinate spikes (to 13 cm long).
Tupistra sumatrensis is unique in having its anthers near the base of the perianth tube, while its stigma is far exserted from the tube (Fig. 2).No other species of Tupistra has a stigma and anthers within a flower so spatially apart from each other as in T. sumatrensis.
Tupistra sumatrensis is one of the most southerly distributed species in the genus.No specimens of other species of the same genus from Sumatra have been seen by the present author.