Proposal (1070) to South American Classification Committee

Transfer the current species of Crypturellus to Tinamus and current species of Tinamus to the genus Pezus

Bertelli et al. (2025) proposed a new classification of the Tinamidae. Among the various changes, they proposed a radical change in the scope of the genera Tinamus and Crypturellus triggered by the argument that the type species for the genus Tinamus is the species currently known as Crypturellus soui. They made the case as follows:

“Specifically, Latham (1783) listed the taxon “Tinamou” without any content or formal description; later, Latham (1790) first listed four species in the genus now spelled Tinamus, i.e. brasiliensis, cinereus, variegatus and soui, all corresponding to Buffon (1778) and other authors, except for Hermann (1783). Then, Gray (1840) designated Tetrao major Gmelin, 1789 (syn. = Tinamus brasiliensis) as type species for Tinamus, but attributed this genus to Latham (1790) and not Hermann (1783). However, there is no doubt that: (1) the form represented in Martinet’s planchet (829) (see Fig. 2) accurately conveys the appearance of the species soui and cannot be confused with other tinamous, thereby confirming that the binomial in Hermann refers to this species and not to any of the much larger and otherwise characteristic forms currently recognized in Tinamus; (2) Buffon’s non-binomial mention and description, and Hermann’s binomial listing of this species, are the same and correspond to the species currently recognized as Crypturellus soui; and (3) the type of Tinamidae should be attributed to Hermann (1783) as generally recognized to this day (e.g. Spix, 1825; Gray, 1867; Sclater and Salvin, 1873; Salvadori, 1895; Conover, 1937; Blake, 1977; Cabot, 2020; Gill et al., 2024), but carrying with it the corresponding recognition of soui as type instead of major.”

Consequently, Bertelli et al. replaced Crypturellus with Tinamus in their paper:

“We recognize Tinamus Hermann, 1783; therefore, Tinamus soui is the type species by monotypy and original designation. Fixation of the type species of a valid Tinamus requires accepting the name combination in the valid oldest source, i.e. Hermann (1783). This apparently minor aspect implies, however, a major rearrangement in the Tinaminae, considering that Tinamus Hermann, 1783 is the valid name designation —not Latham or Gray; and that Tinamus soui Hermann, 1783 is the valid type species; therefore, this name is to be applied to the taxon currently named Crypturellus soui (Hermann, 1783). Then we propose that Tinamus Hermann, 1783 be applied to the small forest tinamous (21 currently recognized species listed below), presently in Crypturellus Brabourne and Chubb, 1914.”

Therefore, they replaced Tinamus for the large forest-dwelling species traditionally placed in that genus with

This rearrangement, which makes use of the name Tinamus, requires a genus to be assigned to the clade inclusive of major, tao, guttatus, solitarius and osgoodi; i.e. historical “Tinamus” including the typical large bodied forest tinamous. An available name is Pezus Spix, 1825, with Tetrao major Gmelin, 1789 as type species (Tinamus major Gmelin, 1789 by subsequent designation in Gray, 1840).”

Morais et al. (2025) recently described a new species of tinamou that they acknowledged was a member of the former Crypturellus clade, but they followed Bertelli et al. and described it as Tinamus resonans – see SACC proposal 1069.

Analysis: We considered two main aspects for analysis. First, we assessed the nomenclatorial effects of Hermann’s work. The consensus is that Hermann was the first to introduce Tinamus as a valid generic name for the species of tinamous known by then, described by Buffon and Latham. But the consensus up to this point was that the type species was fixed as T. major (Gmelin 1789) by subsequent designation by Gray (1840). So, the question is why the ornithological authorities of the past adopted this designation that contrasts with Bertelli’s interpretation of Hermann’s text. The actual text reveals some complexities. After naming the genus Tinamus and describing some diagnostic features, Hermann stated:

“Nec minus illud mirum, dari in hoc genere speciem, Tinamus Soui dictam (…) quae nidum haemisphaericum in arborum ramis ftruat, adeoque hac in re a Gallinaceis plane omnibus discrepet, & Grallis in alto nidifcantibus aliifque quibus ifte inftinctus datus eft, accedat.”

Which translates to:

“Nor is it less strange that there is a species in this genus, called Tinamus Soui (…) which builds a hemispherical nest in the branches of trees, and therefore in this respect it clearly differs from all the Gallinaceae, and approaches the Grouse nesting in the high places and others to which it has been given a name.”

This statement by itself does not constitute a valid type fixation, as just the mention of a species as an example of a genus should not be interpreted as a type designation (Art. 67.5.1). Therefore, T. soui is not a type by original designation (Art. 68.2). But Bertelli et al. argued that T. soui can be considered a type by monotypy. This would be the case if Hermann had mentioned only T. soui as belonging into the genus. However, the very next sentence reads:

“BUFFONIUS Perdicem Americanam f. Tocro, quam veriífimam Perdicis speciem esse judicat, queque & noítra in tabula media interjecta est.”

“Buffon has added to this genus the American Partridge f. Tocro, which he judges to be the truest species of Partridge, which is also interposed in the middle of the table.”

Admittedly, this sentence is difficult to interpret as it suggesting that Buffon added “f. Tocro” to the genus Tinamus but admitting that it is instead a true partridge (“f. Tocro” would be Odontophorus gujanensis). But it is possible that many interpreted that Hermann was mentioning two species in the genus Tinamus and thus type fixation by monotypy would not apply. In any case, a relevant point here is that because Hermann never mentioned T. major, this species is not eligible as a type for Tinamus (Art. 67.2).

Our second, and perhaps most important, consideration is that Bertelli et al. (2025) did not mention much less consider the provision of Prevailing Usage for maintaining stability of nomenclature. The ICZN (1999), under its basic Principles, reads as follows:

“(4) Nomenclatural rules are tools that are designed to provide the maximum stability compatible with taxonomic freedom. Accordingly, the Code recognises that the rigid application of the Principle of Priority may, in certain cases, upset a long-accepted name in its accustomed meaning through the validation of a little-known, or even long-forgotten, name. Therefore the rules must enable the Principle of Priority to be set aside on occasions when its application would be destructive of stability or universality, or would cause confusion. For use in such cases the Code contains provisions that modify the automatic application of the Principle of Priority, whether it concerns the establishment or precedence of names, the fixation of name-bearing types, the spelling of a name, or any other matter.”

In particular, assuming that Hermann’s work implies that the type is T. soui and not T. major, this is a case in which an earlier type fixation was overlooked. The Code considers explicitly these cases in “Chapter 15, Type in the genus group, Article 70. Identification of the type species”:

“70.2. Type fixation overlooked

If it is found that an earlier type species fixation has been overlooked, the overlooked fixation is to be accepted and any later fixations are invalid. If this is considered to cause instability or confusion the case is to be referred to the Commission for a ruling.”

The Tinamus-Crypturellus case is a clear case in which accepting the earlier type fixation by Hermannn would result in considerable instability and confusion because the current use of the genera Tinamus and Crypturellus has been in overwhelming prevailing usage since the creation of the genus Crypturellus. Other than the use of Crypturus Illiger, 1811, instead of Crypturellus, in a few major works between 1914 and Peters (1931), e.g. Chapman (Birds of Colombia 1917, Birds of Ecuador 1926), we are unable to find a single use in print of Tinamus for the Crypturellus clade. The destabilization and confusion created by switching Crypturellus to Tinamus would be substantial and undeniable.

Therefore, we propose maintaining Crypturellus as defined by Brabourne and Chubb (1914) and subsequently followed by all classifications and regional compilations of birds as well as all subsequent research on tinamous. The case must be referred to the Commission for a ruling. In the meantime, as is usual in these cases, we can maintain the current usage. Therefore, we recommend retention of Crypturellus and Tinamus in their current usage and wait for the ICZN ruling.

This case is precisely why the Code has provisions for Prevailing Usage over Priority.

References:

BERTELLI, S., ALMEIDA, F. C., & GIANNINI, N. P. (2025). A new phylogeny and classification of the tinamous, volant palaeognathous birds from the Neotropics. Cladistics, 41(3), 239-263.

BRABOURNE, L, and C. CHUBB. (1914). A key to the species of the genus Crypturus, with descriptions of some new forms and a new genus. Annals and Magazine of Natural History, Series 8, Volume 14, Issue 82, pages 319–322.

HERMANN, J., 1783. Tabula affinitatum Animalium. Imprensis J. G. Treuttel, Argentorati, Strassburg.

MORAIS, L. A., M. A. CROZARIOL, F. I. GODOY, R. A. A. PLÁCIDO, AND M. A. RAPOSO. 2025. A new species of Tinamus (Aves: Tinamiformes) from the western Amazon, Brazil. Zootaxa 5725: 279–291.

Santiago Claramunt and Van Remsen, December 2025

Vote tracking chart:

https://www.museum.lsu.edu/~Remsen/SACCPropChart1044+.htm

Comments from Robbins: “I vote NO, i.e., maintaining Crypturellus for stability!”

Comments from Remsen: “Vitor has my vote on this one, but I have to emphasize that this is a perfect example of WHY the prevailing usage provision of the Code exists: to prevent blind obedience to the principle of priority from disrupting a century of scientific communication.”

Comments from Zimmer: “NO!!!! For all of the reasons laid out in this Proposal. The taxonomic disruption, not to mention the chaotic impact on more than 100 years of literature, that would result from this change, has to outweigh any perceived benefit from even the most generous analysis of this case.”

Comment from Steve Hilty: “To Van and all involved in Neotropical taxonomy:

“Just wish to go on record saying that I am in complete agreement with Glenn Seeholzer and others who question the wisdom of messing with the taxonomic renaming of Crypturellus and Tinamus. What's the point? This does not preserve stability. If fact, it does the opposite.”

Comments from Bonaccorso: “NO. I agree with the rest of the committee that maintaining stability is more important than enforcing priority. I simply suggest keeping this perspective in mind should a similar proposal arise in the future. As an example, the gender-agreement changes implemented more than a decade ago (David & Gosselin 2011, Bull. Br. Ornithol. Club131: 103–115), while nomenclaturally correct, generated considerable disruption in the non-taxonomic community.”

Comments from Naka: “NO. I agree with the general comments and agree in maintaining Crypturellus for Crypturellus and Tinamus for Tinamus!”

Comments from Piacentini (who has Remsen vote): “NO. While it is clear that the original type species of Tinamus is (by monotypy) soui, it had been historically overlooked to a way that such a change of application of Tinamus would threaten the nomenclatural stability - a principle of the ICZN Code stronger than absolute priority. In fact, such a threat had already been noticed over a century ago, when the ICZN Commissioner C. Apstein proposed in 1915 to fix a "new" type for Tinamus (i.e., keeping T. major as type) to conserve the application of the name. So, it was unfortunate that Bertelli et al. (2025) ignored that we now have another century of universal and stable use of Tinamus for the large forest tinamous and, contrary to the Code's principle, proposed to change (and cause confusion) to the nomenclature of almost 60% of the species of the entire family and order. The proper way to go is to ask the Commission to use its plenary power to set aside the original type fixation of Tinamus and declare T. major as the (new) valid type species for the genus. (I can help prepare such a proposal).

Comments from Areta: “NO. The move is destabilizing, and just applying priority makes communication more complicated instead of simplifying it. The spirit of a law is more important than the strict application of a norm that goes against the spirit. So, in this case, using the name Tinamus for Crypturellus and resurrecting Pezus for what we have been calling Tinamus can be seen more as a bureaucratic decision than as a useful move. It is not always clear when flexibility is better than intransigence, but in this case, strict priority seems rigid and problematic. Apstein (1915) had already detected the problem and proposed a solution. I agree with Vitor in that the way to solve this to the benefit of the community of scientific name users is to present a case to the ICZN to use its plenary powers and solve this once and forever. Until then, I oppose to the change."

Comments solicited from Frank Rheindt: [Frank was asked to be the guest voter on this one bur recused himself – see last paragraph.]

“Here is what I would like to add to SACC’s discussion on Tinamus:

“1. Who made Tinamus available? Hermann (1783) seems to be the first to have made Tinamus available. This was in the early days of Linnean taxonomy, when many other authors hadn’t subscribed to Linneaus’s Latin-binomial system yet and continued to publish their names in English (e.g., Latham) or French (e.g., Buffon). The fact that Hermann made this name available in Latin is perhaps by pure chance, given that his entire book was written in Latin. In fact, he specifically alludes to this when saying “…non video quid impediat, quo minus et Latina lingua hoc nomen Tinamus pro designando americano avium genere recipiatur…”, loosely translated that he cannot see a reason why this American bird – called Tinamou – shouldn’t also have a name in Latin. Whatever the circumstances, if he is the first to nomenclaturally make this name available, then his text must be followed closely to establish the list of originally included nominate species (Article 67.2).

“2. What is the list of originally included nominate species of the genus Tinamus? In his description of Tinamus, Hermann (1783) refers to “les tinamous” of Buffon (1778), a work that he uses as an indication. However, because of Article 67.2.3, it is irrelevant which particular species Buffon had originally included in his concept of “les Tinamous”. All that matters is which species are explicitly mentioned by Hermann in his own text. As Van and Santiago point out, Hermann unequivocally considers Tinamus soui to be included in the genus Tinamus. This has led various authors to consider Tinamus soui as the type species by monotypy.

“3. Is Tinamus soui the type species by monotypy? Tinamus soui can only be type by monotypy if there is no other originally included nominate species. Yet Hermann mentions a second species, “Tocro”, which – according to Van and Santiago – is Odontophorus gujanensis (I didn’t double-check this but will assume that it’s correct). This inclusion is odd, as this species is so obviously unrelated to tinamous. Hermann’s exact wording is therefore of importance: “…Huic generi subjunxit Buffonius Perdicem Americanam Tocro, quam verissimam Perdicis speciem esse juidicat, quaeque et nostra in tabula media interjecta est…”. My translation would be: “…Buffon attributed the American Tocro Partridge to this genus, which he considered to be a true partridge, and within which it is also placed in our table…”. Van and Santiago are correct that this is confusing, because Buffon can’t have it both ways: Tocro cannot be a “tinamou” and a “partridge” at the same time. What’s more, in BHL, “Tocro” doesn’t result in a search hit in the corresponding volume of Buffon’s work, so I cannot really trace Buffon’s original statements about Tocro. We can only take Hermann’s text at face value. However, Buffon’s exact statements about Tocro don’t really matter, as our determination of the list of originally included species should only rely on Hermann’s text itself.

“Here is Article 67.2.5 of the Code: “A nominal species is deemed not to be originally included if it was doubtfully or conditionally included, or was cited as a species inquirenda, or as a species incertae sedis.” There are many ways in which Hermann’s sentence about the Tocro can be interpreted, but I consider the most likely reading that Hermann did not consider Tocro to be a tinamou. He himself says – at the very end of his sentence – that he places Tocro among the partridges, not among the tinamous (which are two separate entities in his classification). By extension, the Tocro was only mentioned as a historical curiosity: Hermann likely considered Buffon’s association of the Tocro with tinamous a taxonomic mistake. If this interpretation is adopted, Tinamus soui remains the only “originally included species” within Hermann’s Tinamus, and therefore becomes the type by monotypy. This is important because it means that – for those who don’t mind the prevailing usage problem (see below) – the situation is already fixed. Let’s remember that Gray (1840) designated a type species for Tinamus Latham, 1790, not for Tinamus Hermann, 1783. However, with Tinamus Hermann, 1783 only having a single originally included species, no type species designation is required.

4. Prevailing usage: The voting record in this SACC round is unequivocal: the ornithological community has spoken. South American ornithologists would overwhelmingly prefer to maintain the current status of Tinamus for large species (and Crypturellus for small species). Some mentioned that this is precisely the sort of case that prevailing usage was invented for. Who am I to disagree? Maintenance of traditional name usage would require an ICZN Case, certainly now after Bertelli et al. (2025) have re-initiated the original usage of Tinamus for small species, a feat that can no longer be undone. At the same time, SACC may benefit from the perspective of an outsider with exposure to cases beyond birds:

a. Timeline of an ICZN Case: An ICZN Case can certainly be launched, and it’s good to see that extremely experienced volunteers have stepped forward, such as Vitor, lending their expertise to crafting such a case. Even so, I believe that many SACC members may underestimate the difficulties involved in launching ICZN cases that are meant to challenge name priority. I think it’s fair for me – as a Commissioner of the ICZN – to say that our case system continues to be badly broken. Cases always take several years to be adjudicated upon; some cases have lingered with the Commission for decades (!). If SACC is looking for a quick remedy to this situation, an ICZN Case won’t be it. To be fair, the current ICZN Secretary is doing an absolutely fantastic job in tackling the backlog that had accumulated before his tenure, but the fact remains the same. During the time of adjudication, and despite any recommendations that may be written in the Code, there is typically open warfare between the different camps. In this case, the Bertelli camp may try to further cement their findings by aggressively increasing usage of Tinamus for small species, and vice versa.

b. Feasibility of an ICZN Case: The ICZN receives many cases that seek to overturn priority which were written by authors who underestimate the hurdle. Some authors entirely overlook the instruction that there must be a strong case that “stability be preserved”. Many people think it’s sufficient to mention that a certain name should be preferable because of historic usage, and that’s it. On the other side of the spectrum are some commissioners who argue that prevailing usage should only be used in extreme cases. Real-life examples are cases where everyday household names with common usage in textbooks and industry have been in peril (e.g. Escherichia coli, Tyrannosaurus, Columba livia). Whether an obscure genus of “tinamou” (a word most Commissioners won’t be familiar with) has to undergo a name change is not on most people’s priority list. Hence, the obstacles to a successful case may be more formidable than many taxonomists might assume. A submitting author would have to make a compelling case that such a name change is a true disruption to the entire discipline, not only a minor inconvenience to some field guide authors.

c. Counter-examples: I’m personally often on the fence about many such cases. I know of avian household names that quickly disappeared after they were found to be junior synonyms, without anyone so much as batting an eyelid, and we ended up being fine. In Asia, we lost the genus Crocias (now Laniellus), which is so characteristic that these birds had also been called Crocias in English for a century! Nobody complained, and everyone is fine with calling the Grey-crowned Crocias by the name Laniellus langbianis (not Crocias langbianis). I believe many more such examples can be furnished from birds and other animals. I am not trying to say that the Crocias case is of equal importance as the Tinamus case, but I am saying that we sometimes overestimate the level of instability that genus name changes incur. To some of us, such genus name changes can be exciting and the fodder for stories.

“I won’t vote here. However, in my vote as a Commissioner regarding a potential ICZN case, I will support any well-crafted proposal that makes a strong case for why a change of usage of Tinamus would introduce unacceptable levels of instability. Alternatively, if nobody submits such a strong case, let’s all get ready to refer to Little Tinamous as Tinamus soui, which would currently be the correct usage according to the Code.”