The genus Capparis (Capparaceae) from the Indus to the Pacific

This is a taxonomic revision of the genus Capparis in South and Southeast Asia, Malesia, Australia, and the Pacific. In this area, four sections are distinguished: 1. sect. Capparis, monotypic with C. spinosa, 2. sect. Sodada, monotypic with C. decidua, 3. sect. Monostichocalyx in a new circumscription containing most of the species formerly included in sect. Eucapparis, with about 65 species in the area under revision, 4. sect. Busbeckea, with 12—14 species in all. Of the 79 species recognized, 7 are new, viz. C. cataphyllosa, cinerea, koioides, monantha, pachyphylla, rigida, and rufidula, and 2 are elevated from varietal to specific rank, viz. C. annamensis (C. grandiflora var. annamensis Baker ƒ.) and C. pranensis (C. thorelii var. pranensis Pierre ex Gagn.). Of the 11 subspecies recognized under C. acutifolia, micracantha, and sikkimensis 9 are newly described or new in rank, like 3 out of the 8 varieties under C. loranthifolia, micracantha, and spinosa. Under C. brachybotrya, 2 formae have been maintained, under C. floribunda, is reduced. Three species, C. dielsiana with 2 varieties, C. longipes, and C. muelleriana, have been recorded as incompletely known besides. Chapters on characters and internal relationships, and plant-geographic remarks have been added. All type specimens are cited with the names based on them, the other collections only as far as they are important for the knowledge of the distribution. Notes dealing with deviating specimens, nomenclatural problems, related species in Africa, &c. are given under the taxa. Starting from the idea that solitary large flowers and a beaked ovary with relatively many carpels, the presence of empty spiny bract-like cataphylls at the base of a shoot, and straight thorns are primitive characters, an attempt has been made to devise a subdivision of Sect. Monostichocalyx into 7 tentative Groups to show their natural interrelationships and possible derivation. It is regarded as most likely, that the genus, as represented in the area under revision, originated in southern India/Ceylon and/or Gondwanaland, and migrated into Australia, and later through the Indo-Chinese Peninsula to the northwest and northeast, and into Malesia. An index to numbered collections has been added. Hypselandra Pax & Hoffm. (syn. Meeboldia Pax & Hoffm.) is reduced to Maerua. B.S. Sun’s new taxa from China are discussed in an appendix.