Austinornis, MARSH, 1877

CLARKE, JULIA A., 2004, Morphology, Phylogenetic Taxonomy, And Systematics Of Ichthyornis And Apatornis (Avialae: Ornithurae), Bulletin of the American Museum of Natural History 2004 (286), pp. 1-179 : 52

Austinornis

(New provisional clade name)

DEFINITION: ‘‘Pangalliformes’’ is recommended to be used provisionally as a stembased name ( de Queiroz and Gauthier, 1992) for all taxa/specimens more closely related to Phasianus [ Gallus ] gallus Linnaeus, 1758 than to Anas [Anser] anser Linnaeus, 1758. See Gauthier and de Queiroz (2001: 24) for the form of this name and general rationale for the chosen specifiers. The definition of this name is provisional pending consensus regarding conversion of avian subclade names defined under previous codes and on the form of new major subclade names. Austinornis lentus is identified as a part of Pangalliformes in the phylogenetic analyses (Part II, Results).

DEFINITION: ‘‘ Austinornis ’’ is recommend­ ed to be used provisionally as a stem­based name ( de Queiroz and Gauthier, 1992) for the clade comprised of all taxa more closely related to YPM 1796 ( lentus Marsh, 1877b holotype specimen) than to Phasianus [ Gallus ] gallus Linnaeus, 1758 , Crax rubra Linnaeus, 1758 , and Megapodius freycinet Gaimard, 1823 . The definition of this name is provisional pending (1) conversion of pangalliform subclade names defined under previous codes, (2) further phylogenetic analyses addressing YPM 1796’s position within Pangalliformes, and (3) implementation of a portion of the PhyloCode governing conversion of binomial species names (as are all other names defined and used in this document). The name is proposed for consistency in the application of the species + least inclusive clade couplet approach used here. The ap­ pearance of ‘‘ Austinornis ’’ and the form of clade + species couplets used generally was elected out of awareness that these names will be published during an awkward transitional period prior to decisions concerning conversion of binomial species names from previous codes and prior to the official start date of the PhyloCode. The form of the names is intended to facilitate use by taxonomists during the period prior to the start date of the PhyloCode. This clade would not have been named here had lentus not already been named. Further analysis of pangalliform interrelationships may suggest that lentus should be nominum dubium, and that YPM 1796 is undiagnostic. In that case, both names taking this specimen as a specifier would no longer be valid.

It should also be noted that because YPM 1796 is highly incomplete, its phylogenetic position within Pangalliformes may not be able to be resolved unless further material is discovered. Pending decisions on treatment of such issues in the context of a system of phylogenetic nomenclature, it may be that use of constructions like ‘‘ Pangalliformes lentus ’’ will be formally recommended, and creation of names like Austinornis deemed unnecessary and redundant.