TWO NEW SPECIES OF BEILSCHMIEDIA ( LAURACEAE ) FROM BORNEO

Two new species of Beilschmiedia Nees (Lauraceae) from Borneo, B. crassa and B. microcarpa, are described and illustrated. Beilschmiedia crassa is distinguished from the other Bornean Beilschmiedia species by its thick and strongly coriaceous, narrowly ovate leaves and flowers with a thick receptacle. Beilschmiedia microcarpa is distinct in the combination of the following characters: its glabrous narrow buds, opposite, elliptic, chartaceous leaves with raised veins on the upper surface, flowers with short filaments, and relatively small fruits.


INTRODUCTION
Beilschmiedia Nees is one of the larger genera of Lauraceae (Nishida, 2001) and includes about 250 species distributed mainly in the paleotropics ( Van der Werff, 2001).It is usually distinguished from the other Lauraceae genera by its paniculate or racemose inflorescences not strictly cymose at the terminal division, bisexual and trimerous flowers with six equal to subequal tepals, six to nine fertile stamens with 2-celled anthers, and fruits lacking cupules (Nishida, 1999).
Revisional studies have been made for the genus in several regions: in China and Indochina (Liou, 1934), Taiwan (Liao, 1995), Congo and tropical Africa (Robyns & Wilczek, 1949), Cameroon (Fouilloy, 1974), Madagascar (Van der Werff, 2003), the neotropics (Kostermans, 1938;Nishida, 1999), New Zealand (Wright, 1984) and Australia (Hyland, 1989).However, the genus has still to be revised for the Flora Malesiana region, except for the fact that Kochummen (1989) treated the genus for the Tree Flora of Peninsular Malaysia.Since this region is apparently one of the centres of species diversity for this genus, taxonomic revision of the genus in the region has been awaited.
The author intends to revise the genus Beilschmiedia in the Flora Malesiana region, and is now focusing on the Bornean species.Twenty-eight species (and one variety) were recognized for the genus on the specimen labels from Borneo (Nishida, 2001), but after careful study of specimens including types, only 22 species were confirmed to occur on the island.Besides them, three species were found as new after publishing the checklist (Nishida, 2001).One of them was published recently (Nishida, 2005) and the last two are presented here.

MATERIAL AND METHODS
Specimens used for the descriptions and illustrations were loaned from K, KEP, L, SAN and SAR.To compare these specimens, specimens from A, BO and UC were also examined.All dimensions given are for dried materials except for the floral characters.Flowers were soaked in boiling water before observation and measurement.
Distribution -Endemic to Borneo, known only from Bario and Kapit in Sarawak.
Notes -This species is distinct firstly in its flowers with a thick (c. 1 mm) receptacle.It is very rare for Beilschmiedia to have flowers with a thick receptacle; at least there is no other species with such a character in Borneo, Peninsular Malaysia, Sumatra or Java.In vegetative characters, B. crassa is distinct in the thick and strongly coriaceous, narrowly ovate leaves from the other Bornean Beilschmiedia species.
Beilschmiedia crassa also differs from most of the other Bornean Beilschmiedia species in the flowers with often less than 9 fertile stamens.Flowers of Beilschmiedia have usually 6 or 9 fertile stamens representing the first to third whorls, and in the case with only 6 fertile stamens 3 stamens in the third whorl are sterile.Flowers of B. crassa have 6-9 fertile stamens (usually less than 9), because stamens in the third whorl are  often sterile.Since the flowers do not appear abnormal, this floral feature seems to be a character of this species.Variation in the number of stamens is also seen in the other Beilschmiedia species.Beilschmiedia tooram (Bailey) B. Hyland from Australia sometimes has flowers with 4 or 5 stamens, although there are 6 stamens in a perfect flower (Hyland, 1989).Beilschmiedia hexanthera van der Werff from French Guiana is characterized with 6 fertile stamens representing the first and second whorls, but the author recognized a few flowers with 7 stamens (because of one fertile stamen in the third whorl) even in the type collection.
Habitat & Ecology -Primary forests on hills; on loam soils containing limestone, sandy or clay soils.Altitude up to 1300 m.Flowering: late January, March; fruiting: October, February.
Notes -There are ten opposite-leaved species of Beilschmiedia in Borneo, but among them only B. glauciphylla Kosterm.and this new species share a combination of the following characters: narrow glabrous terminal buds, elliptic leaves and short filaments.The most discriminating character between the two species is in the fruits: fruits of B. glauciphylla are club-or spindle-shaped and large (up to 12 cm long), while the fruits of B. microcarpa are ellipsoid and relatively small (up to c. 3.5 cm long).Flower size is also different: usually c. 4 mm diam. in B. glauciphylla and c. 2 mm diam.This new species was named with the epithet 'microcarpa'.This is because this species has smaller fruits than B. glauciphylla, a species most closely approaching the new species.In fact the fruits of B. microcarpa are not so conspicuously small compared to the other species of this genus.