Proposal (#313) to South American Classification Committee
Adopt the Family Tityridae
Traditionally, Iodopleura, Laniisoma, Tityra, and Pachyramphus were in the Cotingidae, Schiffornis was in the Pipridae, and Laniocera was in the Tyrannidae. Ames (1971) first suggested that Tityra and Pachyramphus be removed from the Cotingidae on the basis of syringeal morphology and placed in the Tyrannidae. Although they were subsequently often associated with one another, Ames actually presented no data indicating any relationship between the two other than as former cotingids transferred to the Tyrannidae.
Allozyme analysis by Lanyon (1985) supported a close relationship between Tityra and Pachyramphus, but with a rather small sampling of other tyrannoids.
Prum and Lanyon (1989) first proposed a tyrannoid suboscine clade including the genera Schiffornis, Laniisoma, Laniocera, Pachyramphus, Xenopsaris, and Iodopleura based on a phylogenetic analysis of syringeal and skeletal morphology. They called this clade the Schiffornis group. Prum and Lanyon specifically examined Tityra and found no shared derived morphological characters uniting it to the rest of the Schiffornis group genera.
Subsequent molecular analyses using a variety of mitochondrial and nuclear DNA sequences supported the existence of a clade including some Schiffornis group members with the addition of Tityra (Chesser 2004; Ericson et al. 2006; Johansson et al. 2002; Prum et al. 2000), but none of these analyses included members of each genus.
Most recently, Ohlson et al. (2007) published the first molecular phylogenetic hypothesis that included all five of six Schiffornis group genera (missing Xenopsaris) and Tityra, and a broad sample of other cotingids. The results confirmed the monophyly of an expanded Schiffornis group to including Tityra. The molecular phylogeny was exactly congruent with the hypothesis of Prum and Lanyon with Tityra including as the sister to Pachyramphus. Molecular data from Xenopsaris are still lacking, but it shares numerous derived syringeal features with Pachyramphus (Prum and Lanyon 1989). The molecular data largely confirm the morphological cladistic characters, with the exception of Tityra having evolved a very divergent (and simplified) syringeal structure since common ancestry with Pachyramphus.
Prum and Lanyon (1989) were unable to resolve the higher level relationships of the Schiffornis group. Prum et al. (2000) placed it as a basal clade of the Cotingidae, but this was based on a very small sample of other tyrannoids. Chesser (2004) placed the clade as the sister to Pipridae, and Johansson et al. (2002) laced them as unresolved in the Tyrannoidea. Ericson et al. (2006) placed them as sister to Tyrannidae, and Ohlson et al. (2007) had them unresolved within Tyrannoidea. Data are still equivocal on the relationship of this clade to other large tyrannoid clades.
Based on these still incomplete molecular
data, Prum et al. (2000) proposed placing the Schiffornis group
genera plus Tityra in the subfamily Tityrinae within the
Cotingidae. Johansson et al. (2002) and Chesser (2004) did not
make any recommendations. Ericson et al. (2006) recommended that
the Schiffornis group genera plus Tityra be placed
in the family Tityridae within the Tyrannoidea, along with Tyrannidae,
Pipridae, and Cotingidae. Relationship among these families is
still unresolved, and nearly every possible combination has been
suggested by one data set or another (or in the case of Sibley
and Ahlquist, two possibilities with the same data set). No recommendation
can be made about a phylogenetic ordering for the tyrannoid families.
In addition, Ericson et al. (2006) and Ohlson et al. (2007) placed the genus Oxyruncus as the sister group to the Schiffornis group genera plus Tityra. As a result, they both recommended that Oxyruncus also be included in the Tityridae. There is some syringeal anatomy support for this hypothesis, but this hypothesis is sufficiently novel, that Oxyruncus should remain Incertae Sedis within Tyrannoidea until some resolution is confirmed by other data sets.
Based on the congruent of morphological and molecular data sets, the genera Tityra, Pachyramphus, Xenopsaris, Iodopleura, Schiffornis, Laniisoma, and Laniocera should be placed in the Family Tityridae G. R. Gray 1832-33 within the Tyrannoidea.
This action should leave only Oxyruncus and Piprites as Incertae Sedis within the tyrannoids.
Ames, P. L. 1971, The morphology of the
syrinx in passerine birds: Peabody Museum of Natural History Bulletin,
Chesser, R. T. 2004. Molecular systematics of New World suboscine birds. Molecular Phylogenetics and Evolution 32:11-24.
Ericson, P. G. P., D. Zuccon, U. S. Johansson, H. Alvarenga, and R. O. Prum. 2006. Higher-level phylogeny and morphological evolution of tyrant flycatchers, cotingas, manakins, and their allies (Aves: Tyrannida). Molecular Phylogenetics and Evolution 40:471-483.
Johansson, U. S., M. Irestedt, T. J. Parsons, and P. G. P. Ericson. 2002. Basal phylogeny of the Tyrannoidea based on comparisons of cytochrome b and exons of nuclear c-myc and RAG-1 genes. Auk 119:984-995.
Lanyon, S. M. 1985. Molecular perspective on higher-level relationships in the Tyrannoidea (Aves). Systematic Zoology 34:404-418.
Ohlson, J. I., R. O. Prum, and P. G. P. Ericson. 2007. A molecular phylogeny of the cotingas (Aves: Cotingidae). Molecular Phylogenetics and Evolution 42:25-37.
Prum, R. O., and W. E. Lanyon. 1989. Monophyly and phylogeny of the Schiffornis group (Tyrannoidea). Condor 91:444-461.
Prum, R. O., N. H. Rice, J. A. Mobley, and W. W. Dimmick. 2000. A preliminary phylogenetic hypothesis for the cotingas (Cotingidae) based on mitochondrial DNA. Auk 117:236-241.
Rick Prum, Sept. 2007
Comments from Remsen: "YES. The Ohlson et al. paper, in my opinion, clinches what we have building toward for many years, namely that this group of genera represents a monophyletic group of equivalent taxonomic rank to Tyrannidae and Cotingidae."
Comments from Stiles: "YES. This group has progressively become better substantiated in successive studies as a monophyletic assemblage of family rank. We have already recognized Oxyruncidae (which as a monotypic family is in a sense equivalent to incertae sedis), and since it has been so treated in many publications over the years, I suggest leaving it as such - at least for now. This would leave Piprites as the only true "incertae sedis" and until its relationships are determined, it should stay this way."
Comments from Stotz: "YES. It has seemed progressively clearer that we were headed toward this and the new molecular data pretty well clinches this change."
Comments from Robbins: "YES. As pointed out by others, the latest molecular data set unequivocally establishes monophyly in this group. I agree with Gary, that we continue to recognize Oxyruncus at the family level, leaving Piprites as the sole "incertae sedis" taxon."
Comments from Nores: "YES. Los datos moleculares muestran claramente que Tityra, Pachyramphus, Xenopsaris, Iodopleura, Schiffornis, Laniisoma y Laniocera conforman un grupo monofilético. Aunque en la propuesta de Prum no está muy claro porque tienen que conformar una familia aparte y no una subfamilia de Cotingidae, en Ericson et al. (2006) y Ohlson et al. (2007) resulta bien evidente."
Additional comments from Remsen: "The most recent Auk has a paper by Barber and Rice that further establishes the monophyly of this group and advocates family rank."
Comments from Zimmer: "YES. Monophyly appears certain, and rank at the family level seems appropriate. Gary's suggestion of retaining Oxyruncus as a monotypic family and leaving Piprites as incertae sedis seems most reasonable."
Comments from Jaramillo: "YES - Great to delete a few more incertae sedis, seems like progress. Data are clear that the family Tityridae is a good choice."