Proposal (1002) to South American Classification Committee

 

 

Recognize the genus Protopelma for Neopelma chrysolophum

 

 

Effect on SACC: Passage of this proposal would replace the name Neopelma chrysolophum with Protopelma chrysolophum .

 

Background: Our current SACC note is as follows:

 

2b. Neopelma chrysolophum was formerly (e.g., Pinto 1944, Meyer de Schauensee 1970, 1979c) considered a subspecies of N. aurifrons, but see Pacheco & Whitney (1995) for evidence for recognition as a separate species, as suggested by Meyer de Schauensee (1966).  Capurucho et al. (2018), Silva et al. (2018), Harvey et al. (2021), and Leite et al. (2021) further found that N. chrysolophum was sister to Neopelma + Tyranneutes, and van Els et al. (2023) described a new genus, Protopelma, for chrysolophum.  SACC proposal badly needed.

 

New information: All recent genetic data indicate that continuing retention of chrysolophum in Neopelma makes that genus paraphyletic with respect to Tyranneutes.  Van Els et al. (2023) summarized all this evidence and named a new genus for chrysolophum to restore monophyly to Neopelma, and they also used vocal and some minor morphological characters to diagnose the new genus.

 

Here is their tree:

 

 

Note that the estimate split of Protopelma from the rest of the subfamily is ca. 11 MYA, i.e. mid Miocene, i.e., typical of lineages ranked as genera based on the traditional eclectic assessment of degree of morphological divergence that delimited most genera until the last three decades.  In this case, morphological evolution is so conservative in this subfamily that there is no shame in failing to recognize how differentiated chrysolophum was from the other taxa, although as outlined in the paper, those like Bret Whitney aware of the voices of these inconspicuous and often patchily distributed taxa like may have had their suspicions.  This is a cool paper – phenotype, at least voice, lines up with genotype.  Here’s their synopsis of the voice of chrysocrotaphum:

 

“Differs from all other members of Neopelminae in at least two conspicuous characters. Firstly, full songs comprise three distinct, multi-syllabic elements, not single elements (Fig. 1A versus Fig. 1B–G). Secondly, all of the notes of the song and calls are sharp and clear, audible at much greater distance than those of any of the other taxa.”

 

The new genus is registered in ZooBank.  It is neuter in gender, so no need to change the variable ending of chrysolophum.

 

The only other solution would be to combine all taxa in a single genus, in which case Neopelma P. L. Sclater, 1861, has priority over Tyranneutes Sclater and Salvin, 1881.  From a phenotypic basis this might be acceptable because Tyranneutes could be viewed superficially as a small Neopelma; and an expanded Neopelma would be no more heterogenous in terms of size and plumage than many bird genera.  But in my opinion this would obscure the important biological point that all these lineages are Miocene in age as well as the point that morphological evolution in this group is exceptionally conservative.  This is what van Els et al. said:

 

“The paraphyly of Neopelma combined with the availability of information on all members of the genus provides an opportunity to revise taxonomy to better reflect evolutionary history. Tyranneutes is characterized by diminutive size, proportionally short tails, and differently structured vocalizations relative to Neopelma sensu lato (see below). They also prefer taller, more mature and more humid forest in general than Neopelma (Whitney et al. 1995). The two species of Tyranneutes are a morphologically, vocally, and ecologically coherent group, so we prefer to maintain them in a genus separate from other members of the complex.”

 

Here’s the plate by J. Wilczur from Handbook of Birds of the World Vol. 9:

 

 

[To be added – photo of specimens]

 

 

 

Discussion and recommendation: This one is as straightforward as it gets in terms of a need to change the classification; use of Protopelma for chrysolophum is required for a phylogenetic classification unless Neopelma is expanded.  So, I strongly recommend a YES on this one.

 

References:

 

VAN ELS, P., M. G. HARVEY, J. M. G. CAPURURCHO, R. T. BRUMFIELD, B. .M .WHITNEY, AND J. F. PACHECO.  2023.  Systematics of the Neopelminae (Aves: Passeriformes: Pipridae) with description of a new genus.  Zootaxa 5361: 135-141.

 

 

Van Remsen, June 2024

 

 

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Comments from Stiles: “YES to recognizing the new genus Protopelma, thus avoiding paraphyly via the lumping of three old lineages including the distinctive Tyranneutes into a single heterogeneous genus Neopelma.”

 

Comments from Areta: “YES. The deep genetic divergence, and vocal distinctions support the recognition of Protopelma. Merging all under an enlarged Neopelma (including the two Tyranneutes and the traditional Neopelma taxa) would create a heterogeneous and deeply diverged genus.”

 

Comments from Claramunt: “NO. I am reluctant to put birds that can barely be distinguished in two different genera. How about lumping Tyranneutes into Neopelma? The genus level is appropriate for accommodating birds that are similar but of different size.”

 

Comments from Robbins: “YES, The genetic data support placing chrysolophum into a new genus, Protopelma.”

 

Comments from Jaramillo: “YES – I think that separating very similar looking birds into different genera based on genetics is disconcerting. But it will happen a bunch in the coming years in seabirds I would say. Like these suboscines, many Procellariiformes barely change in appearance even though they are well differentiated genetically (storm petrels etc.). It is in these vary cases where our senses fail us in seeing difference, that we need to rely more on the genetic work and help it to point out the fact that we did not see this coming given how conservative morphology is in some bird groups.”

 

Comments from Bonaccorso: “YES. Given their morphological similarity, it is tempting to lump chrysocrotaphum and Tyranneutes in Neopelma. However, this lumping will virtually ignore the phylogenetic uniqueness of chrysocrotaphum, which has been evolving independently for about 11 million years! What else besides song has changed in that time? We don´t know, but it seems worth finding out. I´m not fond of monotypic genera, but I think the change is positive regarding recognizing phylogenetic diversity.”

 

Comments from Lane: “YES. I can see the point of maintaining Neopelma for [N.] chrysolophum by sinking Tyranneutes into Neopelma, but to me it’s six of one and half-a-dozen of the other, and Tyranneutes is a nice, diagnosable pair of species, so it seems most logical simply to give chrysolophum a monotypic genus.”