New account of the genus Knema (Myristicaceae)

A tentative subdivision of Knema into 12 series, containing 83 species. The series and species are mainly defined by the shape of the mature male flower bud (perianth) and the androecium, with in addition various vegetative characters primarily concerning the tomentum of the apical part of the twigs, of the lower leaf surface, and of the flowers. This subdivision into series is partly fairly differing from the division into groups poposed by Sinclair in Gard. Bull. Sing. 16 (1958) and 18 (1961), which was mainly based on characters of the female flowers, mainly style and stigma; these latter characters are presently regarded as of less taxonomic significance. A survey of the characters regarded as important in Knema is given. The genus occurs in mainland SE. Asia and Malesia, from India to western New Guinea; not in Ceylon. Of the 83 species, 63 occur in Malesia, and 30 in mainland SE. Asia excluding Malaya and Singapore; 20 species are restricted to that latter area, and most of the remaining 10 species are of Malesian origin, just penetrating into the moist evergreen forest in Peninsular Thailand. Most species occur in Borneo, 39, of which 22 are endemic. A general key to all species of Knema, inside and outside Malesia, based mainly on male flower- and on vegetative characters, is presented. For female flowering and fruiting material five separate regional keys, one for mainland SE. Asia (excl. Malaya and Singapore), and four keys covering the Malesian area, also using in addition vegetative characters, is presented. As compared to Sinclair’s monograph (1961), in which 37 species, 14 varieties, and 1 form were accepted, several species have presently been taken out of synonymy and re-installed, necessitating the redescription of many species. Many of the newly proposed species appeared to be not yet or insufficiently collected at the time of Sinclair's treatment. Description and discussion of the 12 newly proposed series. Enumeration and treatment of all species accepted. Several species have been subdivided into subspecies, varieties, or forms. Besides the 12 new series, 25 new species, 8 new subspecies, 3 new varieties, and 3 new forms are described, and in addition there are several proposals of a new status of already existing taxa. For all new names and combinations, see the index. All extra-Malesian taxa are fully treated, providing for synonymy, typification, description, notes, and enumeration of examined specimens; of the Malesian species usually merely the synonymy, types, some notes, and examined specimens are presented, as full descriptions of these species will appear in Flora Malesiana. An index of all scientific names pertaining to Knema is given at the end.