Proposal (248) to South American Classification Committee

Change English name of Xenornis setifrons

Effect on South American Checklist: This proposal is an attempt to stabilize the English name of a species on our list.

Background: Xenornis setifrons has had a decidedly unstable history regarding its English name. Described by Chapman in 1924, its first proposed English name was Gray-faced Antbird (Eisenmann 1955), a name that no subsequent author has adopted. Meyer de Schauensee (1966, 1970) used "Speckle-breasted Antshrike", which is not inappropriate when attempting to convey the appearance of the female, but which is misleading with regard to the male, which is unmarked gray on the breast. Wetmore (1972) concocted the name "Spiny-faced Antshrike", in reference to the short bristles that surround the loral area and chin of Xenornis. This name was adopted by the AOU for the 1983 Checklist, and was still in use for the Seventh Edition of the Checklist in 1998. Meanwhile, Ridgely (1976) employed the name "Speckled Antshrike", which was subsequently used by Hilty and Brown (1986) and Sibley and Monroe (1990). All of this for a bird that had been seen by only a handful of ornithologists or birders prior to 1985! Ridgely and Tudor (1994) continued the usage of "Speckled Antshrike", and elaborated on their reasons for preferring that name. While acknowledging that Xenornis does have specialized bristles on the face, Ridgely and Tudor argued that these bristles "are virtually impossible to discern in the field". They further argued that "Xenornis is the most generally speckled of all antshrikes." Remsen (1997) provided counter arguments, by pointing out that: 1) although inconspicuous, the facial bristles of Xenornis are of ecological significance (the species frequently sallies to take arthropod prey from often spiny vegetation, and the bristles are thought to protect the eyes {Whitney and Rosenberg 1993; Zimmer and Isler 2003}), and may also be of taxonomic significance, seeing as how this character is also found in the Thamnomanes antshrikes (Schulenberg 1983); and 2) it could be argued that Xenornis is more streaked than speckled, and that in any event, some other species of antshrikes are just as speckled. Zimmer and Isler (2003) went with "Speckled Antshrike" in part because it was more descriptive, and in part because it was the most widely employed name by the various field guides and reference books covering the relatively tiny range of the species.

Analysis: "Gray-faced Antbird" is a terrible name that no one uses, and can be discarded at the outset. "Speckle-breasted Antshrike" is an improvement, but it really only describes the female, and even then, is inadequate, because the female Xenornis is more heavily marked on the back than on the breast. Again, this name predates the period when ornithologists/birders were actually seeing this bird, a period that (to my knowledge) began when John Blake netted the species at Nusagandi, Panama in 1985-86. Remsen's arguments have some merit. Both Mackenziaena leachii (males and females) and Hypoedaleus guttatus (males and females) are distinctly more speckled than Xenornis, and both are antshrikes. Remsen's points concerning the ecological and taxonomic significance of the bristles are also well taken. Even though the bristles are not readily seen in the field (they can be seen at very close range), they are a fairly unique feature among antbirds, and they are, after all, the basis for the species epithet setifrons, which is derived from the Latin seta or saeta, which refers to a bristle, and frons, for forehead or brow. The name "Spiny-faced Antshrike" would therefore agree nicely with the Latin name, while speaking to an ecologically and taxonomically significant character. "Speckled Antshrike" is not inappropriate, just less distinctive, but it does enjoy wider usage in the popular literature.

Recommendation: I don't feel strongly about this one way or the other. In fact, if I had my choice, we'd just call this lone member of a monotypic genus Xenornis, which is what most birders seem to call it anyway. However, in the interest of establishing a truly English name, I'm going to reverse course and go with "Spiny-faced Antshrike" in spite of the fact that I used "Speckled Antshrike" in HBW Volume 8. I like the uniqueness of the name, sort of like Bristle-thighed Curlew. So, my recommendation is for a "NO" vote on changing the English name of Xenornis setifrons.

Literature Cited

EISENMANN, E. 1955. The species of Middle American birds. Trans. Linn. Soc. New York 7: 1-128.

REMSEN, J. V., JR. 1997a. [Review of:] "The Birds of South America. Volume II." by R. S. Ridgely and G. Tudor. Auk 114: 147-152.

RIDGELY, R. S. 1976. A field guide to the birds of Panama. Princeton Univ. Press.

RIDGELY, R. S., AND G. TUDOR. 1994. The birds of South America, vol. 2. Univ. Texas Press, Austin.

SCHULENBERG, T. S. 1983. Foraging behavior, eco-morphology and systematics of some antshrikes (Formicariidae; Thamnomanes). Wilson Bull. 95: 505-521.

WETMORE, A. 1972. The birds of the Republic of Panamá, part 3. Smithsonian Misc. Collect., vol. 150.

WHITNEY, B. M., AND G. H. ROSENBERG. 1993. Behavior, vocalizations and possible relationships of Xenornis setifrons (Formicariidae), a little-known Chocó endemic. Condor 95: 227-231.

ZIMMER, K. J., AND M. L. ISLER. 2003. Family Thamnophilidae (typical antbirds). Pp. 448-681 in "Handbook of the Birds of the World, Vol. 8. Broadbills to tapaculos." (J. del Hoyo et al., eds.). Lynx Edicions, Barcelona.

Kevin J. Zimmer, December 2006

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Comments from Remsen: "NO, for reasons I outlined in 1997."

Comments from Stiles: "NO, for the reasons given by Van and Kevin. "Spiny-faced" describes a unique character while "Speckled" does not."

Comments from Jaramillo: "NO. I do not feel strongly on this one, but agree that Spiny-faced is distinctive and memorable, and we do need a bit more of that in this family."

Comments from Robbins: "NO. Although I agree with Kevin that the best English name would to use Xenornis, I'll vote "no" for making the change from Spiny-faced Antshrike."

Comments from Nores [not an official vote on English names]: "NO. No estoy de acuerdo de mantener un nombre que no es apropiado o por lo menos indica una característica que está mucho menos marcada que en otros integrantes del grupo, a pesar de que haya sido muy usado. Cymbilaimus, Hypoedaleus, Mackenziaena, Frederickena, Thamnophilus doliatus, T. multistriatus, etc. son también "antshrike" y son mucho más "speckled" que Xenornis. Un caso similar es el de Sickle-winged Nightjar que es una característica propia del ave, pero no se ve en el campo."