Proposal
(139) to South American
Classification Committee
Recognize
Coeligena eos as a separate species from Coeligena bonapartei
Coeligena bonapartei was
described by Boissoneau (1840) from Bogotá,
presumably based upon specimens sent to Paris by Goudot (or from some of the
earliest "Bogotá" skins): since it does occur commonly around Bogotá
this seems reasonable as a type locality. C. eos was described
by Gould (1848) from "the highlands of Venezuela and Colombia", later
restricted to Mérida, Venezuela by Wetmore & Phelps (1952). They differ in
plumage characters, males of eos having the secondaries and
tail mostly rufous and a more golden-bronze coloration overall. They were
considered separate species by Cory (1918) and Peters (1945).
However, Wetmore and
Phelps (1952) described the race consita from three females
collected in the Serranía de Perijá on the Colombia-Venezuela border and based
upon its intermediate characters, considered that all three of these forms were
best considered races of a single species. This was followed by Meyer de
Schauensee (1966) and Sibley & Monroe (1990).
However, Schuchmann (1999)
split eos as a separate species from bonapartei (with consita),
and this was followed by Hilty (2002). Schuchmann's rationale was "plumage
characters" but no specific comparisons were presented. Thus, the validity
of the split rests entirely on whether the differences in plumage between eos and consita-bonapartei are
of a magnitude to justify it -- and by implication, whether consita is
sufficiently closer to bonapartei to discard its intermediacy
as a reason for lumping them.
In their description
of consita, Wetmore & Phelps (1952) considered this form closer
to eos than bonapartei because of its
conspicuous rufous spot on the secondaries, which they noted was slightly
smaller than in the former. In ventral pattern, they noted its less spotted
throat and more extensively green breast and sides, its tail and upperparts
greener (the tail entirely golden-green rather than "mostly hazel"),
relative to eos. Compared to bonapartei, consita was
described as more bronzy above, the throat and crissum paler, the abdomen less
greenish. They also noted that in some bonapartei females,
there was a smaller, fainter spot of "brown" (dull rufous) on the
concealed parts of the secondaries. They had no males of consita.
Schuchmann´s (1999) text
confirms that those features present in females of consita and
interpreted as representing intermediacy also occur in males: the rufous area
of the secondaries is smaller than in eos, the overall color is
greener than in eos but more golden-bronze than in bonapartei.
The three appear similar in size, as noted by Wetmore and Phelps (1952),
although Schuchmann (1999) stated that the bill of eos was
"shorter than in other Coeligena". However, judging from
measurements presented by Wetmore & Phelps (1952) for their series of consita,
its bill is also slightly shorter on average than those of a large series of
measurements I have made on female bonapartei. I have also
confirmed the statement by Wetmore and Phelps to the effect that a small dull
rufous area is present on the secondaries of an appreciable proportion of bonapartei of
both sexes. There is a considerable gap between the known ranges of consita and bonapartei
in Colombia, but as noted by Wetmore & Phelps, the intervening area has
been poorly collected (and much of it is dangerous).
Based on the published
data of Wetmore & Phelps and Schuchmann and my own experience with bonapartei,
I believe that Wetmore & Phelps were correct in considering all three forms
conspecific. Indeed, if one were to separate them it is practically arbitrary
whether to consider consita a race of eos or bonapartei,
depending upon which characters one chooses to emphasize. Moreover, the amount
of intraspecific variation in several other undoubted species of Coeligena (iris,
torquata, violifer) equals or exceeds that within a broad bonapartei. I
therefore recommend a NO vote on this proposal.
(I note here that I have
not touched the question of whether to include orina as a race
of bonapartei or as a separate species. FYI, the evidence from
recently collected specimens clearly shows that orina is a
separate species; a publication on this is in progress, and I shall present a
proposal in due course).
Literature Cited:
Boissoneau 1840, Revue Zool. 1840:6
Gould 1848, PZSL 1848:11
Cory 1918, Catalogue of Birds of the Americas, vpl. 2
pt. 1.
Peters 1945, Checklist of Birds of the World, vol. 5
Wetmore & Phelps Jr. 1952, Proc. Biol. Soc. Washington 65:135
Meyer de Schauensee 1966, Species of Birds of South America
Sibley & Monroe 1990, Distribution and Taxonomy of Birds of the World
Schuchmann 1999, Handbook of Birds of the World, vol. 5
Hilty 2002, Guide to the Birds of Venezuela
Gary
Stiles, November 2004
_____________________________________________________________________________________
Voting chart for SACC proposals 100-218
Comments from Remsen:
"NO. There is no published rationale that trumps Wetmore & Phelps
assessment."
Comments from Pacheco:
"[NO. O arranjo
arbitrariamente proposto por Schuchmann não pode ser aceito diante
das informações disponíveis."
Comments from Jaramillo:
"NO. More data are needed to assess if this split is
reasonable."
Comments from Nores: "NO. Las razones son similares a lo de los casos
anteriores. No hay elementos de peso para pasar las subespecies a especies."
Comments from Zimmer:
"NO. Subspecies consita sounds to be perfectly
intermediate, both morphologically and in its geographic distribution."