The flora of California, a global biodiversity hotspot, includes 2387 endemic plant taxa. With anticipated climate change, we project that up to 66% will experience >80% reductions in range size within a century. These results are comparable with other studies of fewer species or just samples of a region's endemics. Projected reductions depend on the magnitude of future emissions and on the ability of species to disperse from their current locations. California's varied terrain could cause species to move in very different directions, breaking up present-day floras. However, our projections also identify regions where species undergoing severe range reductions may persist. Protecting these potential future refugia and facilitating species dispersal will be essential to maintain biodiversity in the face of climate change.

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The present study consolidates knowledge of Antarctic marine Rhodophyta, incorporating new observations from the Antarctic Peninsula. Descriptions of four new genera and five new species are included: Rhodokrambe laingioides (Delesseriaceae), Leniea lubrica, Austropugetia crassa, Varimenia macropustulosa R.L. Moe gens. et spp. nov., and Nereoginkgo populifolia R.L. Moe sp. nov. (Kallymeniaceae). The new combination Trematocarpus antarcticus (Hariot) Fredericq et R.L. Moe is proposed for Kallymenia antarctica Hariot (Sarcodiaceae). Phylogenetic relationships are suggested based primarily on unpublished molecular analyses of rbcL sequences provided by S.-M. Lin, S. Fredericq, P.W. Gabrielson, D.W. Freshwater and M. Volovsek. Habitat and environmental conditions are incorporated from the field studies of R.L. Moe and C.D. Amsler. A preliminary assessment is made of the biogeographic relationships between Antarctic red algae and those found in related temperate regions based on a summary of tectonic and climatic reconstructions of the Cenozoic Southern Ocean and the unpublished phylogenetic studies of Hommersand and his associates.

The thallus formed by the marine pyrenomycete fungus Verrucaria tavaresiae and the phaeophycean alga Petroderma maculiforme was studied to elucidate the organization of the symbionts, determine the type of cellular contacts between them, and evaluate the status of the symbiosis as a lichen. Hand-sectioned and resin-embedded samples were examined with light and transmission electron microscopy. Within the uppermost portion of the cellular fungal tissue, separate algal filaments were arranged anticlinally. Protrusions of the fungal cell wall penetrated into adjacent algal walls but did not enter the cell lumen. A striking feature of these penetrations was the frequent separation of algal cell wall layers and insertion of fungal wall material between them. Algal filaments grew downward intrusively between fungal cells, often penetrating deeply into the fungal cell wall. Despite the exceptional nature of the phycobiont involved, the Verrucaria tavaresiae-Petroderma maculiforme symbiosis unequivocally fits the prevailing concept of a lichen. The distinctive interpenetrations observed between symbionts may be related to the integration of their different growth forms within a coherent tissue regularly subject to mechanical stresses. Periclinal cell divisions within and just below the algal layer may serve to replenish surface tissues lost to abrasion and herbivory.

Summary Silva, P. C. & Moe, R. L.: The Index Nominum Algarum. – Taxon 48: 351‐353. 1999. – ISSN 0040‐0262. The Index Nominum Algarum (ING) is an ongoing project with the goal of producing and maintaining an index of scientific names of algae, both living and fossil, at all ranks. Initiated by Silva in 1949, it now comprises about 180,000 entries. Although it is currently in the form of a card file housed in the Herbarium of the University of California at Berkeley, it is being converted into a database that will be searchable on‐line. Meanwhile, the cards, only about 10% of which are backed by an electronic file, have been archived as digital images on compact discs. An important by‐product of the INA is the Bibliographia Phycologica Universalis (BPU), which now comprises about 65,000 references. Both the INA and the BPU have been made available to the taxonomic community continuously since their inception.