Distribution and Occurrences of Laevilitorina across the Southern Hemisphere

Study Extent

New material was collected from multiple locations in southern South America be-tween The Strait of Magellan (coordinates) and the Diego Ramirez archipelago (56°31.345'S; 68°43.622'W). In the Falkland/Malvinas Islands we collected from the intertidal of Hooker Point (coordinates). New Antarctic material was collected from the South Shetland Islands, Doumer Island, Palmer Land and Avian Island under the framework of Antarctic Scientific Expeditions (ECA) 49, 53, 54 and 58 of the Chilean Antarctic Institute (INACH). Samples from South Orkney Islands and South Georgia were obtained during British Antarctic Survey (BAS) expeditions (2016–2017, 2017– 2018 and 2021). Samples from Kerguelen and Crozet Islands were obtained under the PROTEKER project during the French Polar Institute Paul Emile Victor (IPEV) expedition (2017).

Sampling

The samples were obtained by two methods: 1) manual collection in the intertidal zone were each litorinids were individually sampled and, 2) scuba diving between 1 and 15 m depth, were the substrate (e.g. sediments, macroalgae) were collected. The rocks were subsequently scraped to ensure that all the species and specimens were collected. Also each macroalgal sample was placed in a plastic bag. Geographic positions were recorded using GPS for each sample location. In the laboratory, each sample was gently stirred to detach the associated fauna. All Laevilitorina samples were immediately preserved in ethanol (95%).

Quality Control

Records lacking precise geographic location (coordinates) were assigned georeferences by identification from the description (e.g. bay names, research stations) of the reported collection locality included in the relevant metadata.

Method steps

1. The samples were obtained by two methods: 1) manual collection in the intertidal zone were each litorinids were individually sampled and, 2) scuba diving between 1 and 15 m depth, were the substrate (e.g. sediments, macroalgae) were collected. The rocks were subsequently scraped to ensure that all the species and specimens were collected. Also each macroalgal sample was placed in a plastic bag. Geographic positions were recorded using GPS for each sample location. In the laboratory, each sample was gently stirred to detach the associated fauna. All Laevilitorina samples were immediately preserved in ethanol (95%).

From the sampling carried out at the different sampling sites, morphological observations were performed under an OLYMPUS stereomicroscope CX31. For determination to species level, individuals were identified according to taxonomic revisions by Martens & Pfeffer (1886), Suter (1913), Powell (1951), Powell (1955), Dell (1964), Arnaud & Bandel (1976), Waren & Hain (1996), and Zelaya (2005).

1. Laevilitorina alta
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2. Laevilitorina antarctica
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3. Laevilitorina antipodum
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4. Laevilitorina auckandica
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5. Laevilitorina bifasciata
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6. Laevilitorina bruniensis
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7. Laevilitorina caliginosa
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8. Laevilitorina claviformis
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9. Laevilitorina delli
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10. Laevilitorina granum
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11. Laevilitorina hamiltoni
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12. Laevilitorina heardensis
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13. Laevilitorina johnstoni
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14. Laevilitorina kingensis
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15. Laevilitorina latior
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16. Laevilitorina macphersonae
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17. Laevilitorina mariae
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18. Laevilitorina pygmaea
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19. Laevilitorina umbilicata
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20. Laevilitorina venusta
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21. Laevilitorina wandelensis
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Ten main marine biogeographical provinces in the Southern Hemisphere were considered for the purpose of geospatial analyses, the Magellan province, Antarctic West, Antarctic, East Antarctica, Sub-antarctic islands South Indian Ocean, Sub-antarctic Macquarie, Sub-antarctic New Zealand, Southern New Zealand, Northern New Zealand, West Central Australian Shelf, East Central Australian Shelf, Southeast Australian Shelf and Southwest Australian Shelf as defined in the Marine Ecoregions of the World and the Biogeographic Atlas of the Southern Ocean (Spalding et al. 2007; Koubi et al. 2014) . All spatial analysis were carried out on the unified database.