Supplementary Table 1. Taxonomic designation, sampling location, shell voucher specimen catalogue number (UMMZ: University of Michigan Museum of Zoology; MNHN: Muséum National d’Historie Naturelle, Paris) and GenBank Accession number for every Partula hyalina and P. clara mt COI haplotype employed in the study. Samples obtained recently (since 2002) from wild populations on all seven islands are indicated in blue text. We had two additional sources of Tahitian samples: Burch’s museum specimens collected in 1970 are indicated in black text, and captive Zoo specimens are indicated in red text. The geographical positioning of each sampling location on Tahiti is given in Supplementary Figure 2 and the topological positioning of each haplotype is shown in Supplementary Figure 1. Shell voucher numbers are not available for the biopsied wild samples, nor for a small number of 1970 samples that were damaged during the tissue extraction/lyophilization process.

Morph / Islands / Sampling location / Collector (Year) / # of snails sequenced / Haplotype number / Locality number / Catalogue number / GenBank Accession number
P. clara / Tahiti, Society Is. / Toheimahu River Valley / Burch (1970) / 1 / 96 / 135 / UMMZ300396, 398 / EF062884
Vaitehoro River Valley / 2 / 97 / 152 / UMMZ300435 / EF062885
Vaitepiha Valley / 4 / 107 / 142 / UMMZ300412 / EF062886
Tirahi River Valley / 3 / 94 / 136 / UMMZ300401 / EF062887
Tahiria River Valley / 2 / 88 / 169 / UMMZ300453 / EF062888
1 / 85 / 169 / UMMZ300454 / EF062889
1 / 89 / 170 / UMMZ300456 / EF062890
1 / 85 / 170 / UMMZ300456 / EF062889
Vairaharaha River Valley / 6 / 86 / 165 / UMMZ300426 / EF062891
Moaroa River Valley / 26 / 96 / 120 / UMMZ300382, 383, 386, 388 / EF062892
Taharuu River Valley / 2 / 87 / 125 / UMMZ300393 / EF062893
Paihau River Valley / 4 / 104 / 224 / shell voucher unavailable / EF062894
Faarapa Valley (25m) / Coote (2005) / 1 / 105 / 3 / biopsy / EF062895
Onoheha-Tefaaiti Valley (200m) / Coote (2004) / 1 / 105 / 5 / biopsy / EF062896
Vaipahi River Valley / Coote (2004) / 1 / 96 / 11 / biopsy / EF062897
Taapua Valley (80m) / Coote (2005) / 1 / 97 / 12 / biopsy / EF062898
Papehue River Valley (175m) / Coote (2006) / 1 / 101 / 13 / biopsy / EF062899
Maruapo Valley (120m) / Coote (2005) / 1 / 100 / 14 / biopsy / EF062900
Papenoo-Maroto Valley / Loève (1997) / 2 / 90 / 1 / UMMZ300563 / EF062901
1 / 92 / 1 / UMMZ300563 / EF062902
1 / 91 / 1 / UMMZ300563 / EF062903
Te Pari District / Loève, Spencer & Murray (1995) / 4 / 96 / 3 / UMMZ300562 / EF062904
P. hyalina / Tahiti, Society Is. / Fautaua River Valley / Burch (1970) / 11 / 107 / 144 / UMMZ300413 / EF062908
8 / 107 / 220 / shell voucher unavailable / EF062908
7 / 107 / 222 / shell voucher unavailable / EF062908
2 / 94 / 222 / shell voucher unavailable / EF062909
Tuauru River Valley / 4 / 106 / 211 / UMMZ300483 / EF062910
Tetiairiroa Valley / 1 / 102 / 192 / UMMZ300471 / EF062911
Mapuaura River Valley / 3 / 97 / 131 / UMMZ300395 / EF062912
Tirahi River Valley / 2 / 95 / 138 / UMMZ300407 / EF062913
Afeu River Valley / 4 / 96 / 107 / UMMZ300367 / EF062914
Orofero Valley / 3 / 112 / 99 / UMMZ300360 / EU026162
Tipaerui Valley / 5 / 105 / 217 / shell voucher unavailable / EF062915
Ahonu River Valley (100m) / Coote (2006) / 1 / 106 / 2 / biopsy / EF062916
Haapupuni Valley / Coote, Burch &
Ó Foighil (2005) / 2 / 98 / 4 / biopsy / EF062917
Onoheha-Tefaaiti Valley (140m) / Coote (2004) / 1 / 103 / 6 / biopsy / EF062918
Tahaute Valley (70m) / Coote (2005) / 1 / 103 / 7 / biopsy / EF062919
Vaitoare River Valley (30m) / Coote (2005) / 1 / 99 / 8 / biopsy / EF062920
Raroui River Valley / Coote, Burch &
Ó Foighil (2005) / 1 / 94 / 9 / biopsy / EF062921
1 / 97 / 9 / biopsy / EF062922
Matatia Valley (120m) / Coote (2005) / 1 / 93 / 15 / biopsy / EF062923
Tihiute River Valley (120m) / Coote (2006) / 1 / 111 / 18 / biopsy / EU026163
Tahaute Valley / Loève (1996) / 4 / 93 / 2 / UMMZ300564 / EF062924
Rurutu, Austral Is. / Falises de Matonaa (<10m) / Coote (2005) / 1 / 90 / UMMZ300610 / EU026164
Pte Arei, Peva (<20m) / 1 / 110 / UMMZ300611 / EU026165
Mato Arei, 22.45687S, 151.32423W (10m) / Fontaine & Gargominy (2003) / 1 / 109 / MNHNRr06 / EU026166
S. Paparai, 22.50772S, 151.33412W (60m) / 1 / 109 / MNHNRr36 / EU026167
Rimatara, Austral Is. / 22.63868S, 152.80645W (10m) / Fontaine & Gargominy (2005) / 4 / 97 / MNHNRm31 / EU026168
1 / 108 / MNHNRm31 / EU026169
Tubuai, Austral Is. / 23.38198S, 149.52343W (2m) / Fontaine & Gargominy (2003) / 1 / 97 / MNHNTb11 / EU026170
Raivavae, Austral Is. / 23.85709S, 147.61591W (20m) / Fontaine & Gargominy (2002) / 2 / 107 / MNHNRv39 / EU026171
23.87467S, 147.68989W (90m) / 1 / 107 / MNHNRv71 / EU026172
Mauke,
Cook Is. / Anai’o / Coote (2007) / 2 / 107 / biopsy / EU026173
Tukume / 2 / 107 / UMMZ300612 / EU026174
Mangaia,
Cook Is. / Southern Makatea / McCormack (2006) / 1 / 97 / UMMZ300613 / EU026175
PO1 SW of Bob’s TeRuarui 4m inland of Road / 2 / 97 / UMMZ300614 / EU026176
PO2 TeRuarui / 1 / 97 / UMMZ300615 / EU026177
PO3 TeRuarui / 1 / 97 / UMMZ300616 / EU026178
Stone wall North Makatea track / 1 / 97 / UMMZ300617 / EU026179

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