Benthic communities studies in the Southern Ocean highlight their potential for assessing climate and anthropogenic impacts. However, the lack of standardised methods limits result reliability and interpretation. This dataset presents the first checklist focus on the Antarctic pioneer benthic communities collected using a standardised approach such as Autonomous Reef Monitoring Structures (ARMS) located at 25 m depth in the surroundings of the Italian research station 'Mario Zucchelli' (MZS) in the Terra Nova Bay (TNB) area of the Ross Sea, Antarctica. The data encompass ARMS time series corresponding to deployments of 1, 2, 3 and 5 years, from which 277 occurrence data corresponding to 12 phyla, 43 families, 49 genera and 39 species were obtained. All retrieved specimens are curated by the Italian National Antarctic Museum (MNA, section of Genoa). This dataset is a contribution to the Antarctic Biodiversity Portal, the thematic Antarctic node for both the Ocean Biogeographic Information System (AntOBIS) and the Global Biodiversity Information Facility Antarctic Biodiversity Information Facility (ANTABIF). The dataset was uploaded and integrated with the SCAR-AntOBIS database under the licence CC-BY 4.0. Please follow the guidelines from the SCAR Data Policy (ISSN 1998-0337) when using the data. If you have any questions regarding this dataset, please contact us via the contact information provided in the metadata or via data-biodiversity-aq@naturalsciences.be. Issues with the dataset can be reported at the biodiversity-aq GitHub project.<br> We describe the biodiversity of the Antarctic pioneer benthic communities of TNB sampled using the ARMS installed at the Italian research station 'Mario Zucchelli'. ARMS is a standardised, reproducible and comparable method for quantifying biodiversity. This dataset provides essential baseline data on the occurrence and abundance of pioneer benthic communities in this study area, representing an important contribution for understanding the dynamics of benthic pioneer communities in an area where these structures have never been deployed and, in general, for an exposure time that largely exceed the standard one, which is usually of one year only.<br> The 277 occurrences reported here have been classified at the lowest possible taxonomic level and comprise 39 recognised species, 49 genera and 43 families. Approximately 98% of the samples are stored in 96% ethanol, while the others at -20°C, representing a potential resource for future genetic studies. To date, the entire ARMS collection has not been DNA barcoded, although preliminary metabarcoding analyses have already been published in Cecchetto et al. (2024). Outcomes of the barcoding activity will be the target of another future publication (Cometti et al., in prep). The publication of this data paper was funded by the Belgian Science Policy Office (BELSPO, contract n°FR/36/AN1/AntaBIS) in the framework of EU-Lifewatch as a contribution to the SCAR Antarctic Biodiversity Portal (bio diversity.aq).
