Abstract
Galaxia kamiesmontana and G. parva are new species, both of subgenus Eurystigma. Galaxia kamiesmontana is restricted to the Kamiesberg in Namaqualand, where it grows in shallow soils overlying rock, while G. parva is known only from the Mierkraal flats near Bredasdorp in the southern Cape. Chromosome number is n 9 in G. kamiesmontana and n = 6 in G. parva. Both numbers are new for the subgenus, in which n 8, 7, and 17 have been recorded. The chromosome number in G. kamiesmontana links subgenus Eurystigma to the more specialized subgenus Galaxia in which x = 9 is basic. Chromosome evolution in Galaxia, reviewed in the paper, is seen as having proceeded from a base of x = 9 by aneuploid reduction to n = 8, 7 and ultimately 6 by unequal translocation and centric loss. Galaxia kamiesmontana is evidently a primitive relict species retaining the ancestral basic karyotype, while G. parva, an inbreeding, autogamous species with a highly derived karyotype is one of the most specialized. Galaxia is a small genus of Iridaceae subfamily Iridoideae restricted to the winter rainfall area of the southwestern coast and interior of southern Africa. All species of Galaxia are small corm bearing plants with a basal rosette of short bifacial leaves and Crocus-like flowers with an underground ovary and a perianth tube that raises the flower well above the ground. The flowers are fugaceous, lasting for 3-6 hours, and this, together with their small size, makes the plants very inconspicuous. As a result, the genus is relatively poorly collected. In the recent revision of the genus (Goldblatt, 1979a) I recognized 12 species in two subgenera. The two species described here were discovered subsequent to the publication of the 1979 revision, G. kamiesmontana in 1980 and G. parva in 1981. Both are clearly very local endemics and in view of the high level of knowledge of the Cape Flora, it seems unlikely that they occur elsewhere.
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