Format: ORAL

Kerry A. Ford1, Jos Ignacio Mrquez-Corro2,3, James McCarthy1, Pablo Garca-Moro2, Ana Morales-Alonso2,4, Mara Sanz-Arnal2, Pedro Jimnez-Mejas2, Santiago Martn-Bravo1,2

1 Landcare Research-Manaaki Whenua, Lincoln, New Zealand 2 Botany Area, Department of Molecular Biology and Biochemical Engineering, Universidad Pablo de Olavide, Seville, Spain 3 Jodrell Laboratory, Royal Botanic Gardens, Kew, Richmond, United Kingdom 4 Biodiversity and Conservation Area, Department of Biology and Geology, Physics and Inorganic Chemistry, Universidad Rey Juan Carlos, Madrid, Spain

Carex is a megadiverse genus with about 2000 species of cosmopolitan distribution, which is especially diversified in temperate and cold regions of the Northern Hemisphere. In New Zealand, however, it is remarkably the second largest angiosperm genus with 115 native species (c. 85% endemic), but its study has received comparatively little attention. We provide a general revision of the natural history of Carex in New Zealand, including systematic, biogeographic, ecological, morphological and evolutionary aspects. In the context of the latest dated phylogeny of Carex, New Zealand has been recurrently colonized by multiple lineages via long distance dispersal. Time of colonization seems to have a strong influence in the extent of lineage diversification, probably as a result of more ecological opportunity for diversification for earlier arriving lineages. Two lineages (sects. Echinochlaenae and Uncinia) which concentrate most species diversity (70%) could have undergone evolutionary radiation processes, which is in agreement with molecular evidence, wide ecological and morphological diversity, and relatively uniform chromosome numbers.A wide array of disjunction patterns are revealed by the distribution of non-endemic taxa. On the other hand, restricted endemics shed light on putatively important areas for Carex speciation. Some morphological features are remarkable, including the unique presence of red-leaved species in four different lineages, a feature that could have evolved as a possible adaptation to escape herbivory by the extinct moas. Our revision remarks the extraordinary multidisciplinary interest of the study of New Zealand Carex, and paves the road for future specific research on this group.