Genus Piezophyllus Hope, 1842
Piezophyllus Hope, 1842: 76 .
Piezophilus Hope, 1842: Costa et al. (1992): 879 [unavailable name, incorrect subsequent spelling (ICZN 1999, Art. 33.3)]. Cladocerus Gemminger & Harold, 1869: 1509; synonymized by Hyslop (1921): 664. Coresus Candèze, 1891: 49; synonymized by Fleutiaux (1932): 155.
Dido Arnett, 1955: 600; synonymized by Laurent (1967): 97.
Hopelater Laurent, 1967: 99; synonymized by Costa et al. (1994): 120.
Type species of Piezophyllus . Tetralobus robustus Hope, 1842 (= synonym of P. macrocerus).
Type species of Cladoceru s. Tetralobus macrocerus Laporte, 1838 .
Type species of Coresus . Tetralobus macrocerus Laporte, 1838 .
Type species of Dido . Tetralobus macrocerus Laporte, 1838 .
Type species of Hopelater . Piezophyllus spencei Hope, 1842 .
Literature. Hope (1842): original description; Lacordaire (1857): remarks; Candèze (1859): catalogue; Gemminger & Harold (1869): catalogue; Candèze (1891): catalogue; Fleutiaux (1902): species descriptions; Schwarz (1906): catalogue; Hyslop (1921): information on type species, Schenkling (1925): catalogue; Fleutiaux (1932): species description; Fleutiaux (1935): remark; Fleutiaux (1940): transfer to Tetralobinae; Arnett (1955): remarks on type species; Basilewsky (1958): remark; Laurent (1967): revision; Girard (1971): catalogue, Costa et al. (1992): remark; Calder et al. (1993): remark; Costa et al. (1994): revision; Girard (2003): catalogue, resurrection of Hopelater; Costa et al. (2010): handbook of zoology; Bouchard et al. (2011): nomenclature; Bousquet (2016): remark.
Remark 1. Hyslop (1921) erroneously designated T. spencei Hope, 1842 as the type species of Piezophyllus [see Laurent (1967) for more details].
Remark 2. Hopelater Laurent, 1967 was originally described as a subgenus in Piezophyllus Hope, 1842 . Costa et al. (1994) synonymized Hopelater with Piezophyllus based on a morphological analysis. Girard (2003) erected Hopelater to generic level. Herein, we follow the classification proposed by Costa et al. (1994) until more detailed investigation is carried out.