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.

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.”