[Richard Klim]

Rush, Gaines, Eddleman & Conway 2012. Clapper Rail Rallus longirostris. BNA Online.

Related Species

It is clear that R. longirostris is sister to R. elegans, although even this statement assumes the two are good biological species (e.g., Dickerman 1971, Ripley 1977). Early studies of mitochrondrial DNA variation are inconclusive with regard to species limits (Avise and Zink 1988). If separate species are involved, these two taxa, with R. wetmorei, the Plain-flanked Rail of coastal n. Venezuela, form a superspecies (Sibley and Monroe 1990). But it is perhaps debatable whether R. wetmorei is itself a species, with some arguing it be treated as a distinctive subspecies of R. longirostris (e.g., Meyer de Schauensee 1966). Blake (1977) stated that R. wetmorei occurred sympatrically with R. longirostris in Carabobo, Venezuela, which would seem to settle the matter. . . yet Olson (1997) intriguingly posited that R. wetmorei may not be a taxon at all but is rather a well-marked color morph, one that simply lacks black-and-white barring on the flanks (it is structurally identical to adjacent subspecies of R. longirostris).

Putting R. wetmorei aside, and under the assumption that R. longirostris and R. elegans are biological species, there remains the question of which subspecies to allocate to which species. For example, although subspecies in the obsoletus group are nowadays typically classified with R. longirostris, they have been classified with R. elegans (e.g., Peters 1934, Hellmayr and Conover 1942). By contrast, R. elegans tenuirostris Ridgway, 1874, of central Mexico has been grouped with R. longirostris (e.g., Oberholser 1937, Williams 1989). Species limits may even exceed the traditional two taxa of R. longirostris and R. elegans. For example, Bent (1926) treated the obsoletus group as a separate species. And a recent comprehensive survey of mitochondrial DNA argues for breaking the complex into five separate species (Maley and Brumfield ms.): R. elegans of the e. United States and Cuba; R. crepitans of the Atlantic seaboard, Gulf Coast, Greater Antilles, and Yucatan peninsula; R. obsoletus of w. North America; R. tenuirostris of central Mexico; and R. longirostris of South America. Only time will tell if this taxonomy is found acceptable by the American Ornithologists' Union's checklist committees for North America and for South America.

Regardless, R. longirostris, as currently constituted, hybridizes with R. elegans in brackish marshes where geographic ranges overlap (Meanley and Wetherbee 1962, Meanley 1969, Bledsoe 1988, Olson 1997). Hybrids exhibit a variety of plumage intermediacy (Meanley 1969), and gene flow may partly explain the color morphs of some R. longirostris subspecies.

Maley 2012. Ecological Speciation of King Rails (Rallus elegans) and Clapper Rails (Rallus longirostris). [PhD dissertation]

Proposes four species (tenuirostris is treated as a ssp of R obsoletus):

1. R longirostris (incl phelpsi, margaritae, pelodramus, cypereti, crassirostris)
2. R obsoletus (incl levipes, beldingi, yumanensis, tenuirostris)
3. R elegans (incl ramsdeni)
4. R crepitans (incl waynei, scottii, insularum, saturatus, caribaeus, pallidus, grossi, belizensis, leucophaeus, coryi)

See also: California Clapper Rail (Maley & Brumfield 2009) – but please ignore my unwarranted and crass PS!

Pieplow 2012. King and Clapper Rails. Earbirding.com.

Taylor 1996 (HBW 3):

• King Rail (Rallus elegans)
• Clapper Rail (Rallus longirostris)

[Mysticete]

I've had to bite my tongue on this split for some time now (James Maley is our new collections manager, and gave a presentation on this last spring). Glad to see it finally published!

[Richard Klim]

Originally Posted by Mysticete

I've had to bite my tongue on this split for some time now (James Maley is our new collections manager, and gave a presentation on this last spring). Glad to see it finally published!

When the BNA Online species account for Clapper Rail was revised by Scott Rush & Karen Gaines (19 June), I just did my usual check for any changes to the subspecies recognised - but somehow completely missed the reference to James Maley's recent research! It was only Nathan Pieplow's thought-provoking post on Earbirding.com yesterday that made me check the species account more carefully, and then trace the dissertation.

[Snapdragyn]

Hmm, and if the AOU makes the (unlikely) decision to change the English name of a newly split R. crepitans in order to avoid confusion, one possibility (based on the Latin name 'crepitans') would be 'Rattling Rail' - which would produce a banding code of RARA (rah ah aaa-aah... rah mah, rah mah maaah).

*waits around to see if there are any other pop music fans on the board to get that one*

[Daniel Philippe]

Originally Posted by Snapdragyn

Hmm, and if the AOU makes the (unlikely) decision to change the English name of a newly split R. crepitans in order to avoid confusion, one possibility (based on the Latin name 'crepitans') would be 'Rattling Rail' - which would produce a banding code of RARA (rah ah aaa-aah... rah mah, rah mah maaah).

*waits around to see if there are any other pop music fans on the board to get that one*

You mean the Gaga Rail ?

[Richard Klim]

When AOU recognised R obsoletus 'California Clapper Rail' and R crepitans as distinct species, the latter was just plain, boring 'Clapper Rail'.

[antshrike69]

Originally Posted by Daniel Philippe

You mean the Gaga Rail ?

[GMK]

Originally Posted by Mysticete

I've had to bite my tongue on this split for some time now (James Maley is our new collections manager, and gave a presentation on this last spring). Glad to see it finally published!

Do you know if he (Maley) plans to widen the research and sample Rallus wetmorei?—that particular taxon is positively “Gaga” to be tested genetically. Smithsonian has specimens. If there was some problem in obtaining a sample from there, I could help organise one from a European collection (either BMNH or ZMB), provided he was willing to work with toepads.

[mb1848]

Studies in Avian Biology No. 32 pps. 54-75 Chan et al. (2006) says:

“Based on mitochondrial ATPase8 sequences from a museum specimen R. wetmorei falls within a clade containing both King and Clapper rail sequences (B. Slikas, pers. comm.) and in fact is identical in sequence to King Rail and many Clapper Rails.”

[Robert Gundy]

I'm very new to avian taxonomy, but I have been interested in reptile taxonomy for several years. Have any organizations accepted these splits? My biggest issue with DNA is the use of miniscule sections of DNA that are not at all representative of the genome. How confident is the taxonomic community that ATPase8 is a good marker for delineating species?

[Mysticete]

Hi Robert.

For the split to be recognized, It would have to pass a vote of the AOU checklist committee. I am not aware of whether it is currently up for vote, but you can see the result of previous debates over whether different taxa should be split or not at the AOU NACC home page. AFAIK the split has yet to be recognized by any authority, although I don't think everything Maley has done is published yet.

The AOU never splits on the basis of DNA alone, but they usually require vocal data, morphological differences, and evidence of some sort of reproductive isolation. In the case of the rails, the different taxa involved have very different vocalizations and breeding habits, and so there is substantial evidence that they have reproductive isolation.

Also, IIRC, more than one gene was sampled, and I am pretty sure that both nuclear and mitochondrial DNA was sampled.

[Richard Klim]

Originally Posted by Richard Klim

"...a recent comprehensive survey of mitochondrial DNA argues for breaking the complex into five separate species (Maley and Brumfield ms.): R. elegans of the e. United States and Cuba; R. crepitans of the Atlantic seaboard, Gulf Coast, Greater Antilles, and Yucatan peninsula; R. obsoletus of w. North America; R. tenuirostris of central Mexico; and R. longirostris of South America."

Maley & Brumfield (in press). Mitochondrial and next-generation sequence data used to infer phylogenetic relationships and species limits in the Clapper/King Rail complex. Condor. [abstract]

[njlarsen]

I am curious to see where this one ends: I have two of these forms in the books

Niels

[Jeff hopkins]

Originally Posted by Daniel Philippe

You mean the Gaga Rail ?

Wonder if the scientists will conclude it was "Born this way."

[Richard Klim]

Originally Posted by Richard Klim

Maley 2012. Ecological Speciation of King Rails (Rallus elegans) and Clapper Rails (Rallus longirostris). [PhD dissertation]
Maley & Brumfield (in press). Mitochondrial and next-generation sequence data used to infer phylogenetic relationships and species limits in the Clapper/King Rail complex. Condor. [abstract]

David Ringer, 10,000 Birds, 21 Apr 2013: Clapper and King rails may represent four or five species.

[Richard Klim]

Originally Posted by Richard Klim

David Ringer, 10,000 Birds, 21 Apr 2013: Clapper and King rails may represent four or five species.

Comment from James Maley, 23 Apr 2013...

... In the forthcoming article we suggest common names and detail our reasoning, which goes far beyond mitochondrial clades. As intimated in the article, we also suggest splitting R. e. tenuirostris from the southwest North American group.