Fletcher (1979) stated:-
Pero was included by Herrich-Schäffer in his `Synopsis familiarum Lepidopterorum' which was published first in Syst. Bearbeitung Schmett. Eur. 6: 82-133. The title-page of volume 6 is dated 1843-1856 but Herrich-Schäffer, 1869, CorrespBl. zool.-min. Ver. Regensburg 23: 214, has stated that Heft 68 (which included the Synopsis) was published in 1855; the Heft wrapper is so dated.
The same Synopsis was included in Samml. neuer oder wenig bekannter aussereur. Schmett. 1: 2-52; the title-page of this work is dated 1850-1858 but Gerstaecker, 1857, Arch. Naturgesch. 23 (2): 431, has stated that pages 1-52 were published in 1856. Further information is given in the Introduction to this volume under Dates of some important Publications.
Gonodontis rectisectaria Herrich-Schäffer,  - proposal to conserve its status as the type-species of Pero Herrich-Schäffer, 1855 and to be placed on the Official List of Specific Names in Zoology by Fletcher & Nye, 1983, Bulletin of Zoological Nomenclature 40 (4) : 233.
Parsons et al. (1999) included AZELINA Guenée, 1857; AZELINOPSIS Warren, 1896; EGABRA Walker, 1858 [October]; EUSENEA Walker, 1860 [March]; MARMAREA Hulst, 1896; METICULODES Guenée, 1857; PERGAMA Herrich-Schäffer, 1855 ; STENASPILATES Packard, 1876; and STENODONTA Warren, 1905 as junior synonyms of PERO Herrich-Schäffer, 1855.
Parsons et al. (1999) included 302 species and 5 subspecies (inc. nominates) in the genus PERO.
Pitkin (2002) included Pergama Herrich-Schäffer, 1855; Azelina Guenée, ; Synemia Guenée, ; Meticulodes Guenée, ; Egabra Walker, 1858; Eusenea Walker, 1860; Stenaspilates Packard, 1876; Azelinopsis Warren, 1896; Marmarea Hulst, 1896; Stenodonta Warren, 1905; and Neodontopera Warren, 1906 as junior synonyms of Pero Herrich-Schäffer, 1855.
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