Microciona ambigua n.sp. Bowerbank, 1866: 136; 1874: 65, pl. XXV figs, 1-9.
Hastatus ambiguus : Fristedt, 1885: 31, pl. II figs. 1a-h
Placomia ambigua : Arnesen, 1903: 22, pl. III fig. 5; Arndt, 1913: 119.
Plocamia ambigua : Topsent, 1894: 8; Stephens, 1920: 60, pl. VI fig. 3; Burton, 1930a: 494; Brøndsted, 1932: 15 (including fo. tornotota , fo. tylotota , fo. grandichelata ).
Plocamionida ambigua : Topsent, 1928: 303; Arndt, 1935: 87, fig. 183; Topsent, 1936a: 51; Borojevic et al., 1968: 21; Descatoire, 1969a: 196; Ackers et al., 1992: 137, fig. 153.