Proposal (396) to South American Classification Committee

Establish English names for Phacellodomus ferrugineigula and P. erythrophthalmus

Effect on South American CL: The SACC recently passed Proposal #371, splitting Phacellodomus erythrophthalmus (Red-eyed Thornbird) into two species: P. erythrophthalmus, and P. ferrugineigula, following Simon et al. (2008). We now need to stabilize English names for the two species resulting from the split.

Background: Simon et al. (2008) suggested the English names of “Orange-eyed Thornbird” for P. erythrophthalmus, and “Chestnut-eyed Thornbird” for P. ferrugineigula. Prior to the split, the combined species went by the name of “Red-eyed Thornbird” (e.g. Meyer de Schauensee 1966, Remsen 2003), which was a misleading name with regard to nominate erythrophthalmus, which has glaring orange eyes. The name of “Orange-eyed Thornbird” suggested by Simon et al. for erythrophthalmus is particularly appropriate in highlighting one of the most noticeable features of the bird. An excellent photograph can be viewed at www.birdforum.net/opus/index.php?title=Red-eyed_Thornbird&curid=18100&diff=134068&oldid=134066 after scrolling down one page. See also the video at http://ibc.lynxeds.com/video/red-eyed-thornbird-phacellodomus-erythrophthalmus/bird-bush-alert). Remsen (2003) described erythrophthalmus as having “orange eyes”.

On the other hand, the name “Chestnut-eyed Thornbird” although not inaccurate in describing ferrugineigula, is not particularly helpful. For starters, many individuals have dark reddish eyes (not chestnut) (Remsen 2003; KJZ personal observation). More importantly, the iris color of ferrugineigula is frequently difficult to discern under most field conditions (see: KJZ photo; www.arthurgrosset.com/.../photos/phaery9722.jpg and for a video see http://ibc.lynxeds.com/video/red-eyed-thornbird-phacellodomus-erythrophthalmus/bird-moving-and-singing in which the iris appears to be dull dark red at best.). This species is a real skulker, usually remaining buried in dense vegetation with relatively little light penetration. Under such conditions, the pupil of the eye dilates, essentially obscuring the iris. This happens with erythrophthalmus as well, but the bright orange irides of that species contrast so strongly with the dark pupil that they still stand out. Conversely, the dark reddish or reddish-brown irides of ferrugineigula tend to show little contrast in poor light.

Of all eight currently recognized species of thornbirds (SACC), ferrugineigula is by far the brightest and most extensively rufescent, and the only one that is extensively orange-rufous on the breast (KJZ photos). Remsen (2003) described erythrophthalmus as having “throat dark rufous, blending to olivaceous-brown on underparts”, a description that accurately squares with an examination of live birds and specimens. On the other hand, Remsen (2003) described ferrugineigula as having “orange-rufous of throat extending to breast”, which, again, is supported by an examination of specimens and photos of live birds. In commenting on Proposal #371, KJZ had previously suggested either “Ferruginous Thornbird” or “Ferruginous-breasted Thornbird” for ferrugineigula, either of which would be much more descriptive, as well as being more in keeping with the species epithet, which translates to “ferruginous throated”. Adopting either of these names would ruin the symmetry with the English name of erythrophthalmus that Simon et al. clearly had in mind, but would mean that the name would convey more information regarding the appearance of the bird in the field. Because the split has just been adopted, the name “Chestnut-eyed Thornbird” has not gained any particular traction. In fact, a muddle of English names is now in usage by different entities – with no apparent consensus. These are as follows:

P. erythrophthalmus	P. ferrugineigula	Source
Orange-eyed Thornbird	Chestnut-eyed Thornbird	Simon et al. 2008
Orange-eyed Thornbird	Red-eyed Thornbird	IOC
Red-eyed Thornbird	Orange-eyed Thornbird	IUCN, BirdLife International
Red-eyed Thornbird	Chestnut-eyed Thornbird	SACC (provisional)

MP and JL, while agreeing that “Chestnut-eyed Thornbird” is a poor choice for P. ferrugineigula, objected to both “Ferruginous Thornbird” and “Ferruginous-breasted Thornbird” on the grounds that the color of the underparts are “pale orange” rather than ferruginous. KJZ concedes that the color of the throat and breast of ferrugineigula is closer to orange than to ferruginous, which color more accurately describes the forecrown. A glance at the two species would suggest that one species (ferrugineigula) has the entire throat and breast (extending to but not including the belly) orange-rufous, whereas the other (erythrophthalmus) has an orange throat patch that barely extends to the upper breast. Confronted with the two species, and having to guess which one was called “Orange-breasted”, “Rufous-breasted”, or “Ferruginous-breasted”, would, we suspect, typically result in most people guessing ferrugineigula. After thrashing this around a little, we have concluded that the best English name for ferrugineigula is “Orange-breasted Thornbird”.

As for erythrophthalmus: based on KJZ’s extensive field experience with the species, the glaring orange eyes jump out in the field every time, and any ambiguity in published photos or video is likely an artifact of ambient light and the capabilities of the camera equipment involved. The eye color of erythrophthalmus is also much more of a bright orange than in Freckle-breasted Thornbird (amber) or Greater Thornbird (yellow). MP and JL suggested the name of “Flame-throated Thornbird” as an alternative to an iris-color-based name for erythrophthalmus. This is not a bad alternative, and the name is certainly distinct from that of other thornbirds, and hence, unlikely to cause confusion. However, if we are being sticklers on the use of color (as in objections to ferruginous versus orange or rufous), then the throat color of erythrophthalmus isn’t really “Flame-colored” (think of the colors of Flame-throated Warbler and Flame-colored Tanager). Remsen (2003) described it as “dark rufous”. Again, after kicking it around a bit, we have reached consensus that “Orange-eyed Thornbird” is the best name for this species.

Recommendation: We recommend that the SACC adopt “Orange-eyed Thornbird” as the English name for Phacellodomus erythrophthalmus (following Simon et al. 2008), and that we use “Orange-breasted Thornbird” as the English name for P. ferrugineigula. As a way forward, perhaps we should split this proposal into three parts as follows:

#396a – Accept “Orange-eyed Thornbird” as the English name for Phacellodomus erythrophthalmus as first proposed by Simon et al. Al. 2008. We recommend a “YES” vote on this. A “no” vote should be accompanied by a preferred alternate name. If part “a” of this proposal does not pass, then we will compile a list of all of the suggested alternative names, and re-vote.

#396b – Accept “Chestnut-eyed Thornbird” as the English name for P. ferrugineigula, as first proposed by Simon et al. 2008. We recommend a “NO” vote on this.

#396c – Accept “Orange-breasted Thornbird” as the English name for P. ferrugineigula. We recommend a “YES” vote on this. A “NO” vote on both #396b and c should be accompanied by an alternative English name. If neither b nor c passes, then we will tabulate the suggested alternatives, and re-vote based upon that list.

Literature Cited:

Meyer de Schauensee, R. (1966). The birds of South America and their distribution. Philadelphia: Academy of Natural Sciences.

Remsen Jr., J. V. (2003). Family Furnariidae (ovenbirds). Pp. 162_357. In: Handbook of the Birds of the World, Vol. 8. Broadbills to tapaculos (J. del Hoyo, A. Elliot & D. Christie, eds.). Lynx
Edicions, Barcelona.

Simon, J. E., Pacheco, J. F., Whitney, B. M., Mattos, G. T. & R. L. Gagliardi (2008) Phacellodomus ferrugineigula (Pelzeln, 1858) (Aves: Furnariidae) é uma espécie válida. Revista Brasileira de Ornitologia 16(2): 107-124.

Kevin J. Zimmer, Mark Pearman, & James Lowen, April 2009

Comments from Stiles: “YES to both – the arguments seem reasonable and the names not dissonant or cumbersome.”