Proposal (147) to South American Classification Committee
Recognize Eriocnemis
sapphiropygia as a species separate from E. luciani
This proposal would elevate to species status a taxon (E.
sapphiropygia) considered to be conspecific with E. luciani in all publications
between ca.1945 and 1999, when Schuchmann (1999) separated them.
The forms involved are luciani of extreme S Colombia and
Ecuador, catharina of N Peru and sapphiropygia of C Peru to
Bolivia, all described in the mid-nineteenth century, and baptistae of S
Ecuador, recently described by Schuchmann et al. (2001). The first three were
considered separate species by Cory (1918), and if his sequence of species in Eriocnemis
is anything to go by, he considered catharina closer to luciani than
to sapphiropygia. Chapman (1926)
did not discuss species limits beyond noting that a supposed sapphiropygia specimen
from Ecuador was really a "young luciani". Peters (1945)
lumped catharina and sapphiropygia into luciani without
comment, as was his wont, and this arrangement was followed without questioning
by Zimmer (1951), Meyer de Schauensee (1966), Fjeldså & Krabbe (1990) and
Sibley & Monroe (1990). Zimmer also discussed the diagnostic characters and
distributions of these three forms while describing a new subspecies, marcapatae,
from S Peru (now often not recognized).
The first author to raise sapphiropygia to species rank and
include catharina within it was Schuchmann (1999), who stated that
"intermediate specimens [with luciani] exist, but morphological
differences support treatment as separate species". This split was
accepted by Clements & Shany (2001) and Ridgely & Greenfield (2001)
without comment.
More details on the split were presented by Schuchmann et al.
(2001) in a review of the genus Eriocnemis that included the description
of the southernmost population of luciani as a new subspecies, baptistae,
based mainly on its more bronzy overall coloration. Unfortunately, their
statements and descriptions are not always consistent with those of Zimmer
(1951) or Schuchmann (1999), creating some doubts regarding their conclusions.
Their arguments may be summarized as follows:
a) in external morphology, all
forms of the group are very similar in bill length and length of closed wing;
the only clear-cut difference separating the two races of luciani (luciani,
baptistae) from those of sapphiropygia (catharina, sapphiropygia)
is the length and shape of the tail: tails of the latter are shorter and less
forked than those of the former (lengths of the first and fifth rectrices
presented). No statistics were employed, but the differences in tail shape are
surely significant by inspection (virtually no overlap).
b) the critical forms with regard
to plumage differentiation are the adjacent (albeit separated by a ca. 300 km
gap) baptistae and catharina. The features of catharina
are somewhat equivocal: it shows a tendency toward luciani in its
blue-tinged forehead and lack of at least pronounced coppery on the nape (one
of the features used by Zimmer to distinguish it from sapphiropygia). On
the other hand, the presence of a white midventral "stripe" on the
abdomen in females is shared with the latter. It is greener in overall
coloration than baptistae and sapphiropygia, and males
differ from all other forms in the group in having a strong blue sheen on the
abdomen and more bluish (less violet) lower tail-coverts. Schuchmann et al.
cited specimens showing intergradation between catharina and sapphiropygia
in geographically intermediate localities but provided no detailed
descriptions.
c) Schuchmann (1999) mentioned
"intermediate specimens" between the species luciani and sapphiropygia
(presumably between baptistae and catharina?) but I can find
no mention of these in Schuchmann et al. (2001), which is a bit worrisome.
d) the coppery nape is not
mentioned as a diagnostic feature of the species sapphiropygia (because
it is lacking in catharina??) leading me to wonder about their use
of "Coppery-naped Puffleg" as the English name for this taxon.
In sum, the hard evidence for this split boils down to two
characters: the difference in tail shape (which is in fact much greater than
that found among the races of other polytypic species of Eriocnemis,
viz. E. vestitus) and the ventral pattern of the females (also mentioned
by Zimmer). The characters of catharina are equivocal in several
other respects, although the existence of specimens intermediate between this
form and sapphiropygia (albeit not described in detail) would also favor
uniting it with the latter. The gap in distribution between baptistae and
catharina (if I read Schuchmann et al.'s maps correctly) is large but
may reflect lack of collecting rather than lack of birds, and probably should
not be used as evidence either way at this point. I feel that the more detailed
morphological data of Schuchmann et al. incline the balance in favor of a
split, although I would have been more convinced had they paid more attention
to some of the details mentioned above. Having no personal knowledge of the
forms in question, I am hesitant to make a strong recommendation and await
comments from those with more familiarity with them. For now, a tentative YES
on this proposal.
References
Chapman
1926
Clements
& Shany 2001
Cory 1918
Fjeldså
& Krabbe 1990
Meyer de
Schauensee 1966
Ridgely
& Greenfield 2001
Schuchmann
1999: HBW, vol. 5.
Schuchmann,
K.-L., A-A. Weller & I. Heynen. 2001. Systematics and biogeography of the
Andean genus Eriocnemis (Aves: Trochilidae). J. Ornithol.
142:433-481.
Sibley
& Monroe 1990
ZIMMER, J.
1951b. Studies of Peruvian birds, No. 61. The genera Aglaeactis, Lafresnaya,
Pterophanes, Boissonneaua, Heliangelus, Eriocnemis, Haplophaedia, Ocreatus,
and Lesbia. American Museum Novitates 1540: 1-55.
Gary
Stiles, December 2004
_____________________________________________________________________________________
Comments from Robbins: "NO. I certainly don't find
anything that has been presented that compels one to support the recognition of
Eriocnemis sapphiropygia as a separate species from E. luciani."
Comments from Pacheco: "YES. As informações disponíveis parecem suportar um
"tentativo" sim à proposta."
Comments from Jaramillo: "YES This is difficult, as
the data seems lacking but suggestive that the split is good. I don't know
these taxa, and admit that I am going along with Gary as he has a well-trained
feel for the level of difference shown by species of hummingbirds, and he seems
to be (albeit hesitantly) convinced that this split is good. I apologize for my
lame justification on this one."
Comments from Nores: "SI. Pienso que la forma y tamaño de la cola son caracteres propios de
especies y no de subespecies."
Comments from Remsen: "YES, with reluctance. After
2.5 years, I finally gave up on waiting for comments from our two Peru bird
book authors. Acknowledging all Gary's doubts on the analysis, forced to vote Y
or N, I'll go with Y because (1) Peters and subsequent authors did not provide
rationale for the original lump, and (2) the difference in tail shape, as
Manuel noted, is typically associated with species rank (e.g., the NACC
recognition of multiple species with Chlorostilbon canivetii group).
If hummingbird experts Stiles and Schuchmann are comfortable with species rank,
then so am I."
Comments from Zimmer: "YES. Evidence isn't
overwhelming, but this is another of those unjustified Peters' lumps, and I
think the burden of proof is on that camp."
Additional comments from Remsen: “NO. After the votes and
discussions with Peru book authors Doug and Tom, my weak YES is now a weak
NO. Slight differences in tail shape and
ventral coloration of females is insufficient for treating these as separate
species.