Proposal
(105) to South American
Classification Committee
Recognize
Geotrygon purpurata as a separate species from G. saphirina
Effect on South American
CL: This proposal would split our Geotrygon saphirina into
two species, with recognition of Trans-Andean purpurata as a separate
species.
Background: The
bird we treat as one species, Geotrygon saphirina (Sapphire Quail-Dove),
has three subspecies: (1) trans-Andean purpurata in the
Western Andes from central Colombia to northern Ecuador; (2) cis-Andean
nominate saphirina on the Amazonian slope of the Eastern Andes and
hilly areas of western Amazonia; and (3) (perhaps doubtfully
diagnosable?) rothschildii of the Marcapata Valley in Peru.
This is the traditional classification (e.g., Meyer de Schauensee 1966, 1970,
Goodwin 1983, Hilty & Brown 1986, Sibley & Monroe 1990, Baptista et al.
1997).
The trans-Andean
population differs primarily (as illustrated in Ridgely & Greenfield 2001)
in having a darker, bluer crown; in Baptista et al. (1997), it is also shown as
lacking a white wing spot, and having a darker, redder iris, but these differences
are not shown or mentioned in Ridgely & Greenfield (2001).
New information:
Ridgely & Greenfield (2001) treated purpurata as a
separate species, with the following note:
"G. purpurata is regarded
as a species distinct from cis-Andean G. saphirina (Sapphire
Quail-Dove), based on several striking plumage differences and its disjunct
range."
In the field guide volume,
Ridgely & Greenfield (2001) gave the voice of saphirina as
"Relatively high-pitched (for a dove) song a distinctive quavering 'k-whohh ... k-whohh ...
k-whohh ... "' with pause of about 3
seconds between calls." For purpurata, they stated: "Song (in
Colombia) described as a soft, hollow 'whoot, whoo-oó-oit,' weak and repeated at short intervals (Hilty
& Brown 1986).
The split was followed by
Gibbs et al. (2001).
Analysis:
Without direct comparison of specimens, I can't make any statements concerning
whether the differences between these two are above or below the levels
associated with taxa recognized as species in Geotrygon, but given
that no previous author seems to have treated purpurata at the
species level, I suspect that the differences are not dramatic. The qualitative
descriptions of their voices obviously are intriguing, but Ridgely &
Greenfield (2001) did not mention them in their justification, presumably with
admirable caution until such differences can be studied.
Recommendation: I vote
"NO" on this proposal. Several other similar "splits" that
have been accompanied by qualitative vocal descriptions and some plumage
differences have generally been rejected by SACC, and so I won't repeat here
the arguments associated with those proposals. What I would require, minimally,
for a "YES" vote is a published analysis of presumed homologous
vocalizations from multiple localities within the range of each.
Partial Literature Cited:
BAPTISTA,
L. F., P. W. TRAIL, AND H. M. HORBLIT. 1997. Family Columbidae (pigeons and
doves). Pp. 60-243 in "Handbook of the Birds of the
World, Vol. 4. Sandgrouse to cuckoos." (J. del Hoyo et al., eds.). Lynx
Edicions, Barcelona.
GIBBS,
D., E. BARNES, AND J. COX. 2001. Pigeons and doves. Yale University Press, New
Haven.
GOODWIN,
D. 1983. Pigeons and doves of the world, 3rd ed. Cornell Univ. Press, Ithaca,
New York.
HILTY,
S. L., AND W. L. BROWN. 1986. A guide to the birds of Colombia. Princeton
University Press, Princeton, New Jersey.
MEYER DE
SCHAUENSEE, R. 1966. The species of birds of South America and their
distribution. Livingston Publishing Co., Narberth, Pennsylvania.
MEYER DE
SCHAUENSEE, R. 1970. A guide to the birds of South America. Livingston
Publishing Co., Wynnewood, Pennsylvania.
RIDGELY
, R. S., AND P. J. GREENFIELD. 2001. The birds of Ecuador. Cornell University
Press, Ithaca, New York.
SIBLEY,
C. G., AND B. L. MONROE, JR. 1990. Distribution and taxonomy of birds of the
World. Yale University Press, New Haven, Connecticut.
Van
Remsen, March 2004
________________________________________________________________________________
Voting chart for SACC proposals
100-218
Comments from Robbins:
"I vote "NO" on this proposal despite the fact that these
undoubtedly deserve species status (based on my field experience with both in
Ecuador). Saphirina is quite
distinct from purpurata from a plumage standpoint and if I
recall correctly there is also a size difference (purpurata is larger
than saphirina; specimens at ANSP). Ridgely and Greenfield's
description of saphirina's voice is correct
and I presume Hilty's description of purpurata also
is correct. Nonetheless, someone should write this up in a note."
Comments from Stiles:
"NO. We have specimens of both, and the differences are definite but not
all that striking. (Given the overall conservatism of plumage in the
Columbidae, I am not especially impressed with its value in taxonomic decisions
either for or against species status). The vocalizations would be much better
evidence, but at the least decent recordings should be made:
comparing verbal descriptions, especially by different observers, is doubly
subjective. So, NO at least until good recordings are made (how many
individuals, etc. will depend upon how different they are, at least in part: if
the difference is a quantitative one between generally similar calls/songs,
much more detailed sampling and playback expts. will
be required than if the differences were to be striking and immediately
apparent.)"
Comments from Nores: "NO, aunque la diferencia en voces parece importante. De
ser real esta diferencia sumado a las diferencias
morfológicas yo aceptaría considerarla especie separada, pero por el momento
prefiero no innovar."
Comments from Jaramillo:
"NO Voice information needs to be published somewhere."
Comments from Zimmer: "
NO. Based on described vocal differences, it seems likely that the two taxa do
represent good biological species. However, lacking any published analysis, I'd
have to pass on this split for the time being."