Pannaria minutiphylla Elvebakk and P. pulverulacea Elvebakk are described here as new to science. Both species belong to the panaustral P. sphinctrina (Mont.) Tuck. ex Hue complex. Their spores, however, are more long-ellipsoid and much less verrucose than those of P. sphinctrina itself, and the species are therefore not considered to be phyllidiate and sorediate counterparts, respectively, of the latter. Pannaria minutiphylla disperses with phyllidia, which are distinctly smaller and not as erect as those of a similar Australian species, P. phyllidiata Elvebakk. Pannaria pulverulacea has the smallest vegetative propagules within this species group. They are referred to as soredia here, although they are partly corticated. This species also has the widest distribution, including wet forests of southern South America, south-eastern Australia, and from Northland to Campbell Island in New Zealand. Pannaria minutiphylla has the same distribution and often grows together with P. pulverulacea, except in southern South America, where some related material has still not been sufficiently studied. Both species are very common within their distribution areas, and previously have mostly been identified as P. microphyllizans. The latter is, however, a very different species, which instead will be studied in comparison with P. athroophylla (Stirt.) Elvebakk & D. J. Galloway.

The Waipounamu Erosion Surface is a time-transgressive, nearly planar, wave-cut surface. It is not a peneplain. Formation of the Waipounamu Erosion Surface began in Late Cretaceous time following break-up of Gondwanaland, and continued until earliest Miocene time, during a 60 million year period of widespread tectonic quiescence, thermal subsidence and marine transgression. Sedimentary facies and geomorphological evidence suggest that the erosion surface may have eventually covered the New Zealand subcontinent (Zealandia). We can find no geological evidence to indicate that land areas were continuously present throughout the middle Cenozoic. Important implications of this conclusion are: (1) the New Zealand subcontinent was largely, or entirely, submerged and (2) New Zealand's present terrestrial fauna and flora evolved largely from fortuitous arrivals during the past 22 million years. Thus the modern terrestrial biota may not be descended from archaic ancestors residing on Zealandia when it broke away from Gondwanaland in the Cretaceous, since the terrestrial biota would have been extinguished if this landmass was submerged in Oligocene–Early Miocene time. We conclude that there is insufficient geological basis for assuming that land was continuously present in the New Zealand region through Oligocene to Early Miocene time, and we therefore contemplate the alternative possibility, complete submergence of Zealandia.

Cyrtoctenus wittebergensis sp. nov. is described from a unique holotype from the Witteberg Group of the Cape Supergroup. It is a giant hibbertopteroid eurypterid having combs and specialised movable spines of crytoctenid type (Størmer & Waterston 1968) on the more distal podomeres of the second to fourth prosomal appendages. The function of the combs and their associated movable spines is discussed and it is suggested that together they formed a unique adaptation of eurypterid structures to sweep filter-feeding, the combs forming the filters and the spines the cleaners. The digestive tract is remarkably preserved and shows a spiral valve, posterior to the stomach, which is interpreted as an adaptive feature in this large arthropod to increase the absorptive area of the gut.

The new evidence provided by the South African specimen has required the re-interpretation of the disarticulated Cyrtoctenus specimens previously described from Europe. Disjecta membra recently obtained from the Tournaisian of Foulden, Berwickshire, which may belong to Cyrtoctenus, are described and show characters previously unknown in Scottish material but similar to certain features in the South African specimen.

The taxonomic relationships within the Hibbertopteroidea are discussed in the light of the new combination of characters found in C. wittebergensis. Two families are recognised in the superfamily, the Hibbertopteridae, including Hibbertopterus and Campylocephalus, and the new family Cyrtoctenidae which is here erected to include Cyrtoctenus, Dunsopterus and possibly also Hastimima.