A total of 34 marine algae are reported for the first time based on historical herbarium collections from the marine shores of Tonga in the central South Pacific Ocean: eight Rhodophyta and 26 Chlorophyta. One species of Rhodophyta, i.e. Trichogloea requienii, and four species of Chlorophyta, i.e. Caulerpa plumulifera, Codium extricatum, Udotea glaucescens and Valoniopsis pachynema, represent the first records from central Polynesia. The red alga Titanophora pikeana has only been previously reported in this region from the adjacent western Melanesian islands of Fiji and the isolated Hawaiian Islands to the north. The other 28 algal species are widely distributed marine species around tropical and subtropical islands in the Pacific Ocean.

Hormophysa cuneiformis, a brown macroalga in the family Sargassaceae, is now documented from Pohnpei based on a specimen collected in May 1957 and recently discovered in the Herbarium Pacificum of the Bishop Museum. Previously documented collections of H. cuneiformis in Micronesia were made from Palau in the western Pacific in July 1968 and January 1971, and Pagan Island in the Northern Mariana Islands in July 1975.

We report new records and chorological data for seven French marine algae that make their distribution records more complete. Three species (Erythroglossum lusitanicum, Hildenbrandia occidentalis and Ulva bifrons) are new records for France, two species (Antithamnion hubbsii and Pterocladiella melanoidea) are new records for the French Atlantic coast and two species (Haraldiophyllum bonnemaisonii and Ptilothamnion sphaericum) are new records for the South Atlantic coast of France. Although the Atlantic marine algae of France are well studied, the new findings show that it is still necessary to carry out further floristic studies to complete our knowledge about the marine algae in this region. We describe for the first time mixed phases bearing both cystocarps and tetrasporangia in Lomentaria orcadensis.

The first known collections of marine algae from Santa Rosa Reef, a submerged seamount located 46 km south-south-west of Guam in the Mariana Islands, occurred at 10.0 to 13.7 m depths in 2003 and 2005. Dasycladus vermicularis, a green alga known predominantly from the Caribbean but also reported from the Philippines in 1976 and the Ryukyus in 1995, and Cutleria irregularis, a brown alga first described from the Hawaiian Islands in 2003, represent the first record of D. vermicularis in the Polynesia–Micronesia region, and the first record of C. irregularis in Micronesia. In total, 8 of the 32 algal species collected at Santa Rosa Reef represent new records for the Mariana Islands.

A laminated, partly peloidal lacustrine limestone from the Lower Permian intermontane Döhlen basin in Saxony, Germany, contains one of the most diverse late Palaeozoic tetrapod faunas in Europe associated with a marine higher algal flora of Tethyan character. The surprising co-occurrence of these organisms and the lack of fishes is explained by the special position of this basin above the Elbe lineament, the influence of strong volcanism, of differentiated salinity in the lake and of the palaeowind systems, as well as by the action of stratigraphic, palaeogeographic and palaeoecological filters.