Table S1 Information of specimens sequenced in this study. The individuals which were marked with * were amplified by universal COI primers.

Family / Latin name / ID of speciemen / Collecting locality / GenBank accession No.
genus / Species / 16S / COI
Psammobiidae / Sanguinolaria / elongata / CZG01 / Beihai,Guangxi Province,China / JN859872 / JN859935
CZG02 / Beihai,Guangxi Province,China / JN859873 / JN859936
CZG03 / Beihai,Guangxi Province,China / — / JN859937
CZG04 / Beihai,Guangxi Province,China / JN859874 / JN859938
CZG05 / Danzhou,Hainan Province,China / JN859875 / JN859939
CZG06 / Wenchang,Hainan Province,China / JN859876 / JN859940
CZG07 / Beihai,Guangxi Province,China / JN859877 / JN859941
Sanguinolaria / virescens / LZG01 / Beihai,Guangxi Province,China / JN859878 / JN859942
LZG02 / Beihai,Guangxi Province,China / — / JN859943
LZG03 / Beihai,Guangxi Province,China / JN859879 / JN859944
Sanguinolaria / tchangsii / ZXYBG01 / Lingao,Hainan Province,China / JN859888 / JN859945
ZXYBG02 / Lingao,Hainan Province,China / JN859889 / JN859946
ZXYBG03 / Lingao,Hainan Province,China / — / JN859947
Sanguinolaria / diphos / SXZG01 / Putian,Fujian Province,China / — / JN859948
Sanguinolaria / chinensis / ZGZG01 / Pingtan,Fujian Province,China / JN859880 / JN859949
ZGZG02 / Pingtan,Fujian Province,China / JN859881 / JN859950
ZGZG03 / Nanji,Zhejiang Province,China / JN859882 / JN859951
ZGZG04 / Nanji,Zhejiang Province,China / JN859883 / JN859952
Sanguinolaria / olivacea / ZCXG01 / Rizhao,Shandong Province,China / JN859890 / JN859953
ZCXG02 / Rizhao,Shandong Province,China / JN859891 / JN859954
ZCXG03 / Rizhao,Shandong Province,China / — / JN859955
ZCXG04 / Rizhao,Shandong Province,China / JN859892 / JN859956
Tellinidae / Merisca / capsoides / NXMLG01 / Beihai,Guangxi Province,China / JN859870 / JN859957
NXMLG02 / Beihai,Guangxi Province,China / JN859871 / JN859958
NXMLG03 / Beihai,Guangxi Province,China / — / JN859959
NXMLG04 / Beihai,Guangxi Province,China / — / JN859960
Macoma / tokyoensis / QHBYG01 / Rongcheng,Shandong Province,China / — / JN859961
QHBYG02 / Rongcheng,Shandong Province,China / JN859869 / JN859962
QHBYG03 / Rongcheng,Shandong Province,China / — / JN859963
Macoma / candida / CBYG01 / Beihai,Guangxi Province,China / JN859865 / JN859964
CBYG02 / Beihai,Guangxi Province,China / JN859866 / JN859965
CBYG03 / Beihai,Guangxi Province,China / JN859867 / JN859966
CBYG04 / Beihai,Guangxi Province,China / JN859868 / —
Moerella / iridescens / CHMYG01 / Leqing,Zhejiang Province,China / JN859860 / JN859967
CHMYG02 / Leqing,Zhejiang Province,China / JN859861 / JN859968
CHMYG03 / Leqing,Zhejiang Province,China / JN856862 / —
CHMYG04 / Zhoushan,Zhejiang Province,China / JN856863 / JN859969
CHMYG05 / Guangrao,Shandong Province,China / JN856864 / JN859970
Semelidae / Semele / scaba / CWSDG01 / Lingshui,Hainan Province,China / JN859893 / JN859971
CWSDG02 / Lingshui,Hainan Province,China / JN859894 / JN859972
CWSDG03 / Lingshui,Hainan Province,China / JN859895 / JN859973
CWSDG04 / Lingshui,Hainan Province,China / JN859896 / JN859974
CWSDG05 / Lingshui,Hainan Province,China / JN859897 / —
Semele / cf amabilis / JMSDG01 / Lingao,Hainan Province,China / — / JN859975
Donacidae / Donax / dysoni / XSFG01 / Wenchang,Hainan Province,China / — / JN859976
XSFG02 / Wenchang,Hainan Province,China / JN859898 / JN859977
XSFG03 / Beihai,Guangxi Province,China / — / JN859978
XSFG04 / Beihai,Guangxi Province,China / — / JN859979
XSFG05 / Beihai,Guangxi Province,China / JN859899 / JN859980
XSFG06 / Wenchang,Hainan Province,China / JN859900 / JN859981
XSFG07 / Fangchenggang,Guangxi Province,China / — / JN859982
Solecurtidae / Solecurtus / divaricatus / ZJJC01 / Yangjiang,Guangdong Province,China / JN859884 / JN859983
ZJJC02 / Beihai,Guangxi Province,China / JN859885 / JN859984
ZJJC03 / Haikou,Hainan Province,China / JN869886 / JN859985
ZJJC04 / Beihai,Guangxi Province,China / JN859887 / —
Sinonovacula / constricta / YC01* / Beihai,Guangxi Province,China / JN859901 / JN859986
YC02 / Lianyungang,Jiangsu Province,China / JN869902 / JN859987
YC03 / Panjin,Liaoning Province,China / JN859903 / JN859988
YC04* / Xiapu,Fujian Province,China / JN859904 / JN859989
YC05 / Dalian,Liaoning Province,China / JN859905 / JN859990
YC06* / Shantou,Guangdong Province,China / — / JN859991
YC07 / Dandong,Liaoning Province,China / JN859906 / JN859992
YC08 / Zhoushan,Zhejiang Province,China / JN859907 / JN859993
Sinonovacula / rivularis / JJC01 / Xiamen,Fujian Province,China / JN859908 / JN859994
JJC02 / Xiamen,Fujian Province,China / JN859909 / JN859995
JJC03 / Xiamen,Fujian Province,China / JN859910 / JN859996
JJC04 / Binzhou,Shandong Province,China / JN859911 / JN859997
JJC05 / Binzhou,Shandong Province,China / JN859912 / —
Cardiidae / Vepricardium / coronatum / XBNG01* / Sanya,Hainan Province,China / — / JN860013
XBNG02* / Sanya,Hainan Province,China / — / JN860014
XBNG03* / Sanya,Hainan Province,China / JN859931 / JN860015
Trachycardium / flavum / HBCNG01 / Lingshui,Hainan Province,China / — / JN860016
HBCNG02 / Lingao,Hainan Province,China / JN859932 / JN860017
HBCNG03 / Sanya,Hainan Province,China / JN859933 / JN860018
HBCNG04 / Lingao,Hainan Province,China / JN859934 / JN860019
HBCNG05 / Wenchang,Hainan Province,China / — / JN860020
HBCNG06 / Lingao,Hainan Province,China / — / JN860021
Clinocardium / californiense / JZBNG01* / Dalian,Liaoning Province,China / — / JN860022
JZBNG02 / Qindao,Shandong Province,China / — / JN860023
JZBNG03* / Dalian,Liaoning Province,China / — / JN860024
JZBNG04 / Wenchang,Hainan Province,China / — / JN860025
JZBNG05* / Beihai,Guangxi Province,China / — / JN860026
JZBNG06 / Rongcheng,Shandong Province,China / — / JN860027