Distribution & Ecology: Clipperton (reef crest at low tide); Marquesas; Society (Tahiti); Tuamotu (Ahe and/or Manihi, Hao, Hikueru, Makatea, Makemo, Mataiva, Moruroa, Raroia, Taiaro, Takapoto) - Marine; Shoreline to 10 m; Hard bottom.

Regional Records: CLIPPERTON - Plagusia speciosa - Garth, 1965: 32, figs 21, 22 (Clipperton). - Hendrickx, 1995b: 140 (distribution). - Poupin et al., 2007 (Clipperton new coll.). - FRENCH POLYNESIA - Plagusia speciosa Dana, 1851: 252; 1852b: 369; 1865, pl. 23, fig. 9 ("Waterland" = Ahe and/or Manihi). - Kingsley, 1880c: 223 (Tahiti). - De Man, 1890: 89 (Tuamotu). - Ortmann, 1894: 731 (Tuamotu). - Nobili, 1907: 406 (Hao). - Rathbun, 1907: 36 (Makemo). - Sendler, 1923: 35 (Makatea). - Boone, 1934: 185, pl. 95-96 (Tahiti). - Holthuis, 1953: 34 (Raroia). - Morrison, 1954: 16 (Raroia). - Forest & Guinot, 1961: 162, fig. 177a-c, 178 (Hao, Hikueru); 1962: 74 (Biogeography "Tahiti-Tuamotu, Marquesas"). - Guinot, 1966a: 48 (Raroia); 1985: 454 (List). - Monteforte, 1984: 172, annex 1, tab. a, photograph p. 138a-haut (Makatea, Mataiva, Takapoto). - Delesalle, 1985: 289 (Mataiva). - Salvat & Richard, 1985: 362 (Takapoto). - Poupin, 1994a: 65, fig. 61, pl. 7g (Hao, Hikueru, Taiaro; coll. Frv Marara); 1996a: 3, 72 (Checklist) - Unpublished specimens, ?MNHN - Coll. (remains only) & det. J. Poupin (Moruroa). - Remark: Plagusia immaculata Lamarck, 1818 is erroneously cited from Tahiti and the Tuamotu by Dai & Yang (1991: 563). This error must come from a quick reading of Edmonson (1959: 194), where "Tuamotus (type locality), Tahiti" is mentioned under P. immaculata, but for remarks concerning only P. speciosa Dana. - Unpublished specimens, coll. & det. G. Paulay, Rangiroa, January 10, 2001, Avatoru Motu, ca. 1.5 km E. of Post Office, at Pension Henri (FLMNH-UF 1413).