Proposal (534) to South American Classification Committee
Changes to Pipridae genera and sequence
A. Changes to generic allocation
Background: The phylogeny of the manakins has been investigated substantially over the last 20 years or so, and the arrangement we follow does not completely correspond to the results of either morphological or molecular studies done on the family. Recent molecular studies suggest that we need to make at least some changes in the allocation of species to genera.
Based on syringeal morphology, Prum (1992) concluded that the large manakin genus Pipra was polyphyletic and split the small manakins of the serena group out into the genus Lepidothrix, and recognized Dixiphia for the White-crowned Manakin, P. pipra. The recognition of Lepidothrix has been accepted by nearly all subsequent authors and was part of the original base taxonomy for SACC based on the treatment in Dickinson (2003). Dixiphia has not been accepted by SACC including a recent proposal that considered both Prum’s syringeal data and molecular data from Rego et al (2007). Since that time, two additional molecular studies (Tello et al 2009) and McKay et al (2010) provide additional data regarding relationships in Pipridae.
New information: Since 2007, three studies using DNA sequences have provided data and analysis that bears on this issue. Rego et al (2007) used mitochondrial cytochrome B and rRNA 16S to examine relationships within the Pipridae. They sampled 18 species representing 13 genera. McKay et al. (2010) used two mitochondrial genes (nd2 and col) and a nuclear intron Musk intro 3 to look at Pipridae, sampling 14 species representing 14 genera. Tello et al. (2009) used two nuclear genes (RAG-1 and RAG-2) to look at the broader radiation (Tyrannides) from Tyrannidae though Cotingidae to Pipridae. They sampled a total of 19 manakin species including representatives of all of the relevant genera.
The relevant portions of the trees for Pipridae from all three molecular studies are reproduced below. One thing you will note is that the taxon sampling is not close to complete in any of these studies, but that there is a fair amount of complementarity among the taxa used in the studies. There are a number of things going on, and certainly not complete agreement among the studies. All three studies identify a clade of what I would call classic manakins (plus the weird Heterocercus), including the genera Pipra, “Dixiphia”, Heterocercus, Manacus, Lepidothrix, and Machaeropterus. There is some disagreement on the relationships among these genera. However, one subclade is consistently returned by all 3 studies. That clade contains Machaeropterus, Pipra (or Dixiphia) pipra, and the cornuta species group of Pipra (represented by rubrocapilla, erythrocephala and/or mentalis in the three studies). The remaining species of Pipra (the aureola species group) do not cluster with these taxa in the Rego et al (2007) or the Tello et al (2009) studies. Unfortunately, McKay et al. (2010) lacked a representative of the aureola group.
The clade with Machaeropterus, Pipra pipra and the cornuta group does not have a consistent topology in the 3 studies. Rego et al. (2007) have Machaeropterus interposed between Pipra pipra and the cornuta group, whereas the other two studies have Machaeropterus at the base of the clade.
It appears from these studies that the genus Pipra even with the removal of Lepidothrix and “Dixiphia” pipra is not monophyletic. The generic name Pipra belongs with the aureola group. That group seems to form straightforward clade. There are 3 generic names associated with the clade that includes the cornuta group currently placed in Pipra. Dixiphia is the oldest name, and P. pipra is the type. Machaeropterus applies to those species currently in that genus and Ceratopipra would be the appropriate name for the cornuta group.
There would seem to be 3 possible treatments for the Dixiphia, Machaeropterus, and Ceratopipra clade. A) The taxa could all be placed in the genus Dixiphia, the oldest name for the group. B) The three names available could all be used, recognizing Machaeropterus as currently defined, Dixiphia as monotypic, consisting of just pipra, and Ceratopipra for the cornuta group. C) Retain Machaeropterus and place pipra and the cornuta group in Dixiphia. The first two treatments are consistent with all three molecular studies. The third, however, conflicts with the tree of Rego et al. Thus, I think the two appropriate options are using Dixiphia for all these taxa or the 3-genera treatment. Because Machaeropterus stands out morphologically, in plumage pattern and behavior from the other species, I am disinclined to place all species in Dixiphia.
Rego et al. (2007) tree:
Tree from Tello et al (2009):
Tree from McKay et al (2010):
The molecular data clearly indicate that Pipra as currently constituted is not monophyletic. So I recommend removing Pipra pipra, cornuta, chloromeros, rubrocapilla, and erythrocephala from Pipra. Two possible treatments for the clade found in all three studies including these species plus the genus Machaeropterus are possible: A) All taxa placed in the genus Dixiphia, the oldest name for the group. B) The three names available could all be used, recognizing Machaeropterus as currently defined, Dixiphia as monotypic, consisting of just pipra, and Ceratopipra for the cornuta group. Because Machaeropterus stands out morphologically, in plumage pattern and behavior from the other species, I am disinclined to place all species in Dixiphia, and recommend choice B.
B. Sequence of genera in Pipridae
Assuming that SACC splits Pipra, and basically accepts the results of these molecular studies, we need to adjust the order of genera in Pipridae to reflect the results from these molecular studies. All 3 studies have Tyranneutes and Neopelma basal. They also identify two clades, one consisting of Ilicura, Masius, Corapipo, Antilophia, Chiroxiphia, and Xenopipo. The other clade contains the remaining genera: Pipra, Lepidothrix, Manacus, Heterocercus and Dixiphia (sensu lato). The topology of the first clade seems well-established. Xenopipo is basal, Antilophia and Chiroxiphia are sisters, Masius and Corapipo are sisters, and Ilicura is sister to them.
The other clade has much more variation across the 3 studies, and bootstrap values for much of the structure are poor. However, as noted in part A, a clade containing Machaeropterus, Dixiphia, and Ceratopipra is returned by all three studies, and a sequence of those taxa with Dixiphia between the other two is consistent with all of the topologies. The remaining genera, Pipra, Lepidothrix, Manacus, and Heterocercus, have very different arrangements in the three studies. A sequence of Manacus, Heterocercus, Pipra, and Lepidothrix seems like it would best reflect the potential relationships suggested in these studies.
So I recommend we place the genera of Pipridae in the following sequence, which is consistent with the molecular topologies and maintains the current sequences as much as possible:
Dickinson, E. C. (ed.). 2003. The Howard and Moore complete checklist of the birds of the World, Revised and enlarged 3rd Edition. Christopher Helm, London, 1040 pp.
McKay, B. D., F. K. Barker, H. L. Mays, Jr., S. M. Doucet, and G. E. Hill. 2010. A molecular phylogenetic hypothesis for the manakins (Aves: Pipridae). Molecular Phylogenetics and Evolution 55:733-737.
Prum, R. O. 1992. Syringeal morphology, phylogeny, and evolution of the Neotropical manakins (Aves: Pipridae). American Museum Novitates 3043.
Rego, P. S., J. Araripe, M. L. V. Marceliano, I. Sampaio, and H. Schneider. 2007. Phylogenetic analyses of the genera Pipra, Lepidothrix and Dixiphia (Pipridae, Passeriformes) using partial cytochrome b and 16S mtDNA genes. Zoologica Scripta 2007:1-11.
Tello, J. G., R. G. Moyle, D. J. Marchese, and J. Cracraft. 2009. Phylogeny and phylogenetic classification of tyrant-flycatchers, cotingas, manakins and their allies (Aves: Tyrannides). Cladistics 25:429-465.
Doug Stotz, July 2012
Comments from Zimmer: “A. YES. I would concur with Doug’s rationale for choice “B”: That is, to retain Machaeropterus as currently defined, restrict Dixiphia to pipra (which is more than one species anyway), and move the cornuta group (including chloromeros, in addition to the species sampled) to Ceratopipra. Given the distinctiveness of Machaeropterus, I just can’t see lumping everything into Dixiphia. B. YES to Doug’s proposed sequence, which makes the most sense while minimizing upheaval.”
Comments from Stiles: “A. YES to B, especially as the display behavior of pipra is really quite different from that of at least erythrocephala and mentalis and setting it apart also fits Prum’s morphological data.”
Comments from Pacheco: “A. Yes. B. YES. A sequźncia me parece consistente com os dados recentes disponíveis, incluindo uma proximidade na sequźncia entre Dixiphia e Machaeropterus.”
Comments from Stiles: “YES, including the recognition of three genera: Ceratopipra, Dixiphia and Machaeropterus.”
Comments from Pérez-Emán: “A: YES. Data are consistent with recognition of Dixiphia, Machaeropterus, and Ceratopipra. B: YES. Sequence is consistent with what we know so far about these taxa, while creating the fewest changes.”
Comments from Jaramillo: “YES - for both A and B. The final arrangement makes sense and is based on various solid data.”
Comments from Nores: “Changes to generic allocation. YES, choice B. The resurrection of the genus Ceratopipra is consistent with the Rego et al. study, but conflicts with the trees of Tello et al. and the McKay et al. Note, however, that this does not mean eliminating the genus Machaeropterus, which groups a set of species quite similar in color to each other and different from the rest.
Sequence of genera in Pipridae. NO. Following the criteria of the taxon that splits first (presenting the lesser number of ancestors, that is, internal nodes) being placed at the top of the sequence and so on, we obtain the following sequences of the trees of Rego et al., Tello et al. McKay et al. and a new sequence.
SACC Stotz Rego et al. Tello et al. McKay et al.
Neopelma Neopelma Neopelma Neopelma Neopelma
Tyranneutes Tyranneutes Tyranneutes Tyranneutes Tyranneutes
Ilicura Ilicura Xenopipo Xenopipo Lepidothrix
Masius Masius Antilophia Antilophia Heterocercus
Corapipo Corapipo Chiroxiphia Chiroxiphia Manacus
Machaeropterus Antilophia Manacus Ilicura Machaeropterus
Lepidothrix Chiroxiphia Lepidothrix Corapipo Dixiphia
Manacus Xenopipo Heterocercus Masius Ceratopipra
Antilophia Machaeropterus Pipra Heterocercus Xenopipo
Chiroxiphia Dixiphia Dixiphia Manacus Antilophia
Xenopipo Ceratopipra Machaeropterus Lepidothrix Chiroxiphia
Heterocercus Manacus Ceratopipra Machaeropterus Ilicura
Pipra Heterocercus Dixiphia Corapipo
Pipra Ceratopipra Masius
Proposed new sequence: