Proposal (237 and 238) to South American Classification Committee
Proposal 237: Change linear sequence of forest Tinamidae genera
Proposal 238: Change linear sequence of Nothocercus species
Proposal 237: This proposal is to change the current linear sequence of the forest Tinamidae genera (Tinamus, Nothocercus and Crypturellus) to make it consistent with recently published molecular and morphological phylogenies. Currently, the sequence is:
A "YES" vote to this proposal would change to:
Proposal 238: Separately, the species sequence of Nothocercus is as follows:
A "YES" vote to this proposal would change to:
Discussion of generic sequence in Tinamidae: A published phylogeny based on morphological data held Nothocercus to be sister to all other Tinamidae; with Tinamus sister to all genera other than Nothocercus; and Crypturellus sister to the remaining (aridland) genera (Bertelli et al. 2002). A phylogeny based on molecular (mtDNA) data held Nothocercus to be sister to (Tinamus + Crypturellus), these three forest genera together forming one of two broad Tinamidae lineages: "forest" and "aridland" (Porzecanski 2003). A strict consensus phylogeny combining both data sets found Tinamus + Crypturellus (1) to be sister, with Nothocercus (2) and aridland Tinamidae (3) forming three Tinamidae lineages (Bertelli & Porzecanski 2004). A single most optimal phylogeny using the combined data produced similar results to the molecular tree as regards the relationship between these three genera (Bertelli & Porzecanski 2004). The current linear sequence is not consistent with any of these hypotheses. However, moving Nothocercus to the start of the linear sequence would be consistent with all of them.
No other elements of the current generic sequence on SACC appear materially inconsistent with the Bertelli & Porzecanski (2004) phylogenies.
Species sequence in Nothocercus: A separate implication of Bertelli et al. (2002) and Bertelli & Porzecanski (2004) is that Nothocercus julius is sister to (N. bonapartei + N. nigrocapillus). The latter two species share a number of morphological features not found in N. julius, including one structural character (absence of rounded ocelli on the thigh) and between two and seven plumage characters (Bertelli et al. 2002). The current SACC species sequence is inconsistent with such a relationship.
Note on species sequences in other genera: The Tinamus SACC sequence is not inconsistent with the Bertelli & Porzecanski (2004) phylogeny and requires no change. The Crypturellus SACC sequence is inconsistent with these phylogenies in various respects. However, Crypturellus species level relations and species limits are controversial and difficult (see e.g. Proposals 209-211). Given that the studies referred to above did not include molecular data for all distinctive taxa in the genus Crypturellus, I do not raise a proposal to deal with the species sequence. Finally, I do not consider the aridland genera here due to a lack of familiarity with them.
Recommendations: A "YES" vote to each, for the reasons given above.
Bertelli S. & Porzecanski A.L. 2004. Tinamou (Tinamidae) systematics: a preliminary combined analysis of morphology and molecules. Ornitologia Neotropical (Suppl.) 2004. (available at http://www.arches.uga.edu/~perdiz/pdf/bertelli_&_porzecanski_2004.pdf)
Bertelli S., Giannini, N.P. & Goloboff, P.A. 2002. A phylogeny of the tinamous (Aves: Palaeognathiformes) based on integumentary characters. Syst. Biol. 51:959-979.
*Porzecanksi, A.L. 2003. Historical biogeography of the South American aridlands: a molecular study of endemic avian taxa. Doctoral thesis. Columbia University, New York. (*Note: I have not seen this but have relied in the above discussion on trees reproduced in Bertelli & Porzecanski (2004).)
Thomas Donegan, August 2006
Comments from Stiles: "Morphological and genetic data both support the change, so YES."
Comments from Stotz: "YES. Fits biogeographically as well as Crypturellus and Tinamus are basically lowland taxa, while Nothocercus is Andean."
Comments from Jaramillo: "YES - Data look solid, and nothing is obviously "off" with this new arrangement. The Bertelli and Porzecanski data suggest that perhaps lumping Tinamotis with Eudromia is reasonable, but this may be a question of taste."
Comments from Pacheco: "YES. Os resultados parecem bem comportar a posição de Nothocercus no início da sequência."
Comments from Stiles: "Although a genetic analysis would be nice, the morphological data supporting the proposal look good, so YES."
Comments from Stotz: "YES. Unfortunately, I am swayed mostly by my sense of these species, rather than the data presented in the proposal, which is only moderately convincing."
Comments from Pacheco: "YES. Vejo a proposição, baseada em dados morfológicos, como um avanço à sequência tradicional, sendo portanto favorável a sua implementação."