Wikipedia
The "Passerae" were a proposed " parvclass" of birds in the Sibley-Ahlquist taxonomy. This taxon is a variation on the theme of " near passerines", birds that were - and often still are - believed to be close relatives of the passerines (perching birds, which include the songbirds). This proposed taxon was roundly rejected by subsequent cladistic analyses.
According to Sibley and Ahlquist, they include the following superorders and orders:
- Superorder Cuculimorphae
- Order Cuculiformes
- Superorder Psittacimorphae
- Order Psittaciformes
- Superorder Apodimorphae
- Order Apodiformes
- Order Trochiliformes
- Superorder Strigimorphae
- Order Musophagiformes
- Order Strigiformes
- Superorder Passerimorphae
- Order Columbiformes
- Order Gruiformes
- Order Ciconiiformes
- Order Passeriformes
Notable orders traditionally considered "near passerines" but not placed in the Passerae of the Sibley-Ahlquist taxonomy are Coliiformes, Coraciiformes, Piciformes and Trogoniformes (see below for why this is significant).
While the Sibley-Ahlquist taxonomy certainly represents a monumental endeavour and has some strong points (namely the recognition of the Galloanserae), basically everything about this "parvclass" is today regarded as utter fiction, brought about by the methodological and analytical problems of the phenetic DNA-DNA hybridization analysis. The "Passerae" are one of the most seriously flawed systematic proposals in modern ornithology, perhaps rivalled only by the suggestion (based as it was on early cladistic analyses) that Hesperornithes, Gaviiformes and Podicipediformes form a monophyletic group. In sheer scope of their falseness, however, the "Passerae" are in post- Linnean ornithology matched only by the ecomorphology-based "taxa" of Charles Lucien Jules Laurent Bonaparte's mid-19th century Conspectus Generum Avium.