Nye (1975) stated:-
Descriptions of Pachythrix hampsoni sp.n., as for Trachea smaragdistis Hampson sensu Hampson, 1908, ibidem 7: 137, pl. iii, fig. 2. Very similar to Euplexia smaragdina Bethune-Baker, 1906, Novit. zool. 13: 195, from New Guinea, but differs in distribution and in the postmedial fascia of the forewing, almost straight anteriad in smaragdina but excurved in hampsoni.
See Frontispiece, fig. 7, Pachythrix hampsoni sp. n., holotype - male; fig. 8, Euplexia smaragdina Bethane-Baker, male.
Hampson, 1908, ibidem 7: 137, 159, placed both E. smaragdina Bethune-Baker, 1906, and Hadena smaragdina Neumoegen, 1883, in the same genus Trachea Ochsenheimer, 1816. E. smargdina Bethane-Baker thus became a junior secondary homonym and Hampson proposed for it the objective replacement name Trachea smaragdistis Hampson, 1908, ibidem 7: 137, pl.III, fig. 2, but actually described and figured an Australian species not nonspecific with smaragdina Bethune-Baker. Warren, 1912, Novit. zool. 19: 21, noted this misidentification and proposed for smaragdina Bethune-Baker another objective replacement name Euplexia smaragdifera Warren, 1912, so as to leave 'smaragdina [lapsus for smaragdistis] Hampson standing for the Australian [species]'. In doing this was in or and should instead have named the misidentified Australian species described and figured by Hampson.
Trachea smaragdistis Hampson, objective replacement name for Euplexia smaragdina Bethune-Baker is here transferred to Pachythrix Turner (comb. n). Although E. smaragdina Bethune-Baker is thus no longer a junior secondary homonym, it was rejected as such prior to 1961 and under the Code, Article 59(b)(i), is not to be restored as the valid name.
Pachythrix Turner has a misidentified type-species and under the Code Article 70 (a), should be referred to the Commission.
Poole (1989) included PACHYTHRIX in the subfamily AMPHIPYRINAE, subsequently restricted to the genus AMPHIPYRA by Kitching & Rawlins, in Kristensen (1999). Other genera formerly treated in the subfamily AMPHIPYRINAE are treated as HADENINAE by Kitching & Rawlins (loc. cit.).
Poole (1989) included 2 species in the genus PACHYTHRIX.
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