The surface geology of the Prince Edward Islands: refined spatial data and call for geoconservation

Volcanological maps of the sub-Antarctic Prince Edward Islands were first published in 1968, with a revised surface geology map of Marion Island produced in 2006. These maps have been widely used in terrestrial studies on the Prince Edward Islands but they have limitations in spatial accuracy and detail. Using high-resolution satellite imagery and digital elevation data, more spatially accurate data for both Prince Edward and Marion Island’s surface geology are presented here. In particular, Marion Island’s volcanology on the western coast, including the 1980s lava flow, and the newly exposed Central Highland following the disappearance of extensive ice and snow cover is mapped with greater detail and verified through field observations. The spatial data are downloadable as ESRI layer packages, which can assist in future investigations of island biotic-abiotic processes and interactions and enable improvements in spatial modelling. In addition, this paper highlights geological features and specimens from the Prince Edward Islands as unique examples of geodiversity in a South African context. An overview of these features are provided in terms of their geoheritage value to enable a more comprehensive geoconservation strategy be incorporated into the Prince Edward Islands Management Plan.

The distribution of four species of the genus Macrourus (Gadiformes: Macrouridae) from the Southern Ocean based on samples from the toothfish longline fishery

The known distribution of Macrourus caml is extended to the Ob and Lena Banks area, and southwest of Heard and McDonald Islands. Macrourus holotrachys was recorded from Prince Edward Islands and the Ob and Lena Banks. Macrourus carinatus specimens examined were all from Prince Edward Islands, the type locality. Macrourus whitsoni specimens examined were all from the southeast Atlantic Ocean at about 69˚S, close to the Antarctic continent (off Maud Land), consistent with a previous study which reported the species from 64–77˚S. A revised identification key is provided.

Two new subscpecies of Antarctic horsefish (Zanclorhynchus, Scorpaeniformes: Congiopodidae) from Indian Sector of Southern Ocean

The goal of this work is to revise the endemic South Ocean species Zanclorhynchus spinifer, one of the most numerous demersal fish species inhabiting waters off subantarctic islands. Despite its high abundance and significant role in trophic chains, the species remained poorly described. Morphological parameters were studied for the first time on a significant amount of material; individual variability was clarified for a number of parameters. Such variability, according to some characteristics, is beyond the range of values previously used in the description of the species, and the occurring break of the infraorbital canal was previously considered to be characteristic in the family Congiopodidae only for the sister genus Alertichthys. The two new subscpecies Zanclorhynchus spinifer armatus subsp. nov and Z. spinifer macquariensis subsp. nov. are described in this paper in addition to the nominative subspecies and the previously described subspecies from the seamounts of the Pacific Ocean sector of the Southern Ocean Z. spinifer heracleus. Type series were collected in the Indian sector of Southern Ocean off the Prince Edward Islands and the Crozet Islands from the depth 170–310 metres, and off the Macquarie Island from the depth 21–84 meters. New subscpecies well differs from other two subcpecies Z. spinifer spinifer and Z. spinifer heracleus with arming of the head and first dorsal fin, scales and body proportions. A key to the species and subspecies of the genus Zanclorhynchus is presented.