E 1). Of the clades represented by more than three specimens, only clade A (n = 161) is restricted to the Scotia Arc, while clade B (n = 24) is restricted to the Falklands/Burdwood Bank. Even representatives of very rare clades, such as K (n = 2) and O (n = 4), are found in widely distant regions. None of the clades found in this study seem to show a truly circumpolar distribution as they are notably absent in entire well-sampled regions in our sampling. For example, clade D1, which is known from the South Orkneys/South Shetlands, the Eastern Weddell Sea and Terre Ad ie/George VTable 1. Number of specimens per COI GMYC clade in each location. The total number may be larger than the sum of numbers for individual regions as some specimens lack locality information. Colours refer to those used in figure 1.S. Sandwich Islands S. Shetland Islands Falkland Islands Elephant Islandrsos.royalsocietypublishing.org R. Soc. open sci. 2:…………………………………………W. Ant. Penins.Balleny IslandsE. Weddell SeaAmundsen SeaE. Ant. Penins.South GeorgiaBouvet IslandScott Seamts.Terre Ad ieS. OrkneysRoss SeaA B C D1 D2 D3 E1 E2 F G H I J K L M N1 N2 N3 O 1 47 24……………………………………………………………………………………………………………………………………………………………………………………………….Land, was not found in South Georgia or the South Sandwich Islands. Specimens of distinct clades often occur sympatrically in the same regions, especially LOXO-101 site around the South Orkneys (six clades) and the South Shetlands (seven clades), and even occur at the same sampling station as in the case of station 11740 in the South Shetlands where 22 individuals from five different clades were collected. The haplotype network for clade A (figure 5) shows a `star-like’ pattern centred around the common haplotype A-2 (n = 106). All other 27 haplotypes from the South Sandwich, South Orkney and South Shetland Islands differ from it by only one to three substitutions and are known from only one to three samples (except for A-7 from Elephant Island with n = 7). Compared to all other regions, there is much more variability in South Georgia, with haplotype A-2 occurring less frequently compared with other regions (figure 5). For clade D1, there is a clear differentiation between eastern (Terre Ad ie/George V Land, n = 6) and western (South Orkneys/South Shetlands/Western Antarctic Peninsula/Eastern Weddell Sea, n = 101) specimens, with the latter forming a star-like pattern that is mostly due to the large number of specimens with haplotype D1? from the South Orkneys. However, a single specimen from East Antarctica (haplotype D1?4) groups closer to the western specimens (figure 5).CladeChileTotal161 24 1 12 5 2 1 107 5 7 1 1 3 24 93 3 1 1 5 3 33 1 1 1 12 16 10 73 1 2 2 1 3 3 3 2 3 8 5 1 15 23 32 1 4 1 1311Table 2. Differences in COI clade delimitation in C. megalonyx based on single-threshold GMYC (same results as bGMYC) and ABGD. Numbers in rightmost column refer to ITS clades to which individuals from the respective COI clade are assigned. n/a RWJ 64809 site refers to COI clades for which no ITS sequences were available. clade A B C GMYC A B C ABGD A B C ITS group IV, VI I I, IIrsos.royalsocietypublishing.org R. Soc. open sci. 2:…………………………………………………………………………………………………………………………………………………………E 1). Of the clades represented by more than three specimens, only clade A (n = 161) is restricted to the Scotia Arc, while clade B (n = 24) is restricted to the Falklands/Burdwood Bank. Even representatives of very rare clades, such as K (n = 2) and O (n = 4), are found in widely distant regions. None of the clades found in this study seem to show a truly circumpolar distribution as they are notably absent in entire well-sampled regions in our sampling. For example, clade D1, which is known from the South Orkneys/South Shetlands, the Eastern Weddell Sea and Terre Ad ie/George VTable 1. Number of specimens per COI GMYC clade in each location. The total number may be larger than the sum of numbers for individual regions as some specimens lack locality information. Colours refer to those used in figure 1.S. Sandwich Islands S. Shetland Islands Falkland Islands Elephant Islandrsos.royalsocietypublishing.org R. Soc. open sci. 2:…………………………………………W. Ant. Penins.Balleny IslandsE. Weddell SeaAmundsen SeaE. Ant. Penins.South GeorgiaBouvet IslandScott Seamts.Terre Ad ieS. OrkneysRoss SeaA B C D1 D2 D3 E1 E2 F G H I J K L M N1 N2 N3 O 1 47 24……………………………………………………………………………………………………………………………………………………………………………………………….Land, was not found in South Georgia or the South Sandwich Islands. Specimens of distinct clades often occur sympatrically in the same regions, especially around the South Orkneys (six clades) and the South Shetlands (seven clades), and even occur at the same sampling station as in the case of station 11740 in the South Shetlands where 22 individuals from five different clades were collected. The haplotype network for clade A (figure 5) shows a `star-like’ pattern centred around the common haplotype A-2 (n = 106). All other 27 haplotypes from the South Sandwich, South Orkney and South Shetland Islands differ from it by only one to three substitutions and are known from only one to three samples (except for A-7 from Elephant Island with n = 7). Compared to all other regions, there is much more variability in South Georgia, with haplotype A-2 occurring less frequently compared with other regions (figure 5). For clade D1, there is a clear differentiation between eastern (Terre Ad ie/George V Land, n = 6) and western (South Orkneys/South Shetlands/Western Antarctic Peninsula/Eastern Weddell Sea, n = 101) specimens, with the latter forming a star-like pattern that is mostly due to the large number of specimens with haplotype D1? from the South Orkneys. However, a single specimen from East Antarctica (haplotype D1?4) groups closer to the western specimens (figure 5).CladeChileTotal161 24 1 12 5 2 1 107 5 7 1 1 3 24 93 3 1 1 5 3 33 1 1 1 12 16 10 73 1 2 2 1 3 3 3 2 3 8 5 1 15 23 32 1 4 1 1311Table 2. Differences in COI clade delimitation in C. megalonyx based on single-threshold GMYC (same results as bGMYC) and ABGD. Numbers in rightmost column refer to ITS clades to which individuals from the respective COI clade are assigned. n/a refers to COI clades for which no ITS sequences were available. clade A B C GMYC A B C ABGD A B C ITS group IV, VI I I, IIrsos.royalsocietypublishing.org R. Soc. open sci. 2:…………………………………………………………………………………………………………………………………………………………
