Watson, Fletcher & Nye (1980) and Fletcher & Nye (1982) stated:-
A junior homonym of Aza Mulsant, 1850, Annls Soc. Agric. Lyon (2) 2: 424, 1085, - Insecta, Coleoptera. There is no objective replacement name, but A. micacea is congeneric with Colla glaucescens Walker, 1865, the type-species of Colla Walker, 1865; the latter is thus available for use as a subjective replacement name.
Aza was established in the Liparidae, now Lymantriidae; it was placed in the Bombycidae, Epiinae (now included in the Apatelodidae) by Schaus, 1929, in Seitz, Gross-Schmett. Erde 6: 679, who included the type-species in Colla. Schaus, 1927, in Seitz, ibidem 6: 537, included Aza in the Lymantriidae and stated that the type of Aza micacea was lost. Two syntypes, one male and one female, have since been found in the BMNH and A. micacea is placed in that collection as a senior subjective synonym of Colla albescens Schaus, 1905, Proc. U.S. natn. Mus. 29: 299.
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