環蛸枕

環蛸枕（學名：），又名林西海膽，是一屬已滅絕的海膽。牠們生存於晚白堊紀至上新世。其化石分佈在非洲、亞洲、歐洲、北美洲及南美洲。

特徵 
環蛸枕是一種很小、緊密的心海膽，在其前端有很突出的深凹口，線條分明的花瓣狀步帶長有孔。頂盤上四個大生殖孔用於排放卵和精子。牠們生活在鬆軟沉積的洞穴裡。

物種 
 Linthia aguayoi Sánchez Roig, 1949
 Linthia alta Sánchez Roig, 1949
 Linthia arabica Clegg, 1933
 Linthia atolladosae Sánchez Roig, 1951
 Linthia avilensis Sánchez Roig, 1949
 Linthia balboi Airaghi, 1939
 Linthia boreasteria Nisiyama, 1968
 Linthia brodermanni Sánchez Roig, 1949
 Linthia bulgarica Gocev, 1933
 Linthia caraibensis Jeannet, 1928
 Linthia cretacica Sánchez Roig, 1949
 Linthia dainellii Stefanini, 1928
 Linthia darderi Lambert, 1935
 Linthia desioi Airaghi, 1934
 Linthia garciai Sánchez Roig, 1952
 Linthia gibba Lambert, 1933
 Linthia gonzalezmunozi Sánchez Roig, 1952
 Linthia hanoverensis Kellum, 1926
 Linthia hargeisensis Currie, 1943
 Linthia heimei Jeannet, 1936
 Linthia hollandi Barry, 1942
 Linthia maverickensis Gardner, 1933
 Linthia mortenseni Checchia-Rispoli, 1950
 Linthia mullerriedi Lambert, 1935
 Linthia obesa Arnold & H.L. Clark, 1934
 Linthia praenipponica Nagao, 1928
 Linthia pseudoglobalis Thirring, 1936
 Linthia rolandi Castex, 1930
 Linthia somaliensis Currie, 1927
 Linthia suitensis Jeannet, 1936
 台灣林西海膽 Linthia taiwanensis Hayasaka, 1948
 Linthia trechmanni Hawkins, 1924
 Linthia yessoensis Minato, 1950

參考文獻 

H
H
H
H
H
台灣化石