Proposal (142) to South American
Classification Committee
Split Heliangelus
clarisse from H. amethysticollis, lump H. spencei into H.
clarisse
This
proposal would essentially overturn the revision of Zimmer (1951), as followed
by Meyer de Schauensee (1966) and most subsequent authors, and return to the
taxonomy of Peters (1945), as proposed by Schuchmann (1999), followed by Hilty
(2002).
A
considerable number of forms in this genus were described as separate species
prior to the synthesis of Cory (1918), often based upon very minor differences
in male plumages; the problem is exacerbated by the fact that the group as a
whole is morphologically quite uniform, as well as by the number of apparent
hybrids and aberrant forms described from one or two specimens and evident
confusion regarding type localities in a few cases. It thus seems best to start
with Cory (1918), who listed four species in the group: spencei of
Venezuela, Clarisse of NE Colombia, laticlavius of E
Ecuador and = amethysticollis of E Peru and E Bolivia (ignoring several
forms of dubious affinities or status, and leaving aside strophianus
of W Ecuador and extreme SW Colombia, which seems to be clearly distinct; see
below). This was essentially followed by Chapman (1926), who did not
mention spencei. In 1945, Peters reduced this group to two species,
clarisse + spencei and laticlavius + amethysticollis, without
comment.
The
first serious revision of the group was that of Zimmer (1951), who described
the race decolor from NE Peru, essentially filling in the gap between E
Ecuador and SE Peru, comparing it in some detail with laticlavius and amethysticollis.
He then stated that "Clarisse belongs in the amethysticollis
group" without further comment, and mentioned several characters
justifying separating spencei as a separate species including
color and "texture" of the male's gorget and throat pattern of
females. He also noted numerous characters of both sexes justifying maintaining
species status for strophianus. The differences between the three
southern races were in details of the color of the males' gorgets, frontlets
and pectoral bands and the grayness vs. rufescence, as it were, of their lower
underparts; variation in most characters seems rather of a mosaic type rather
than showing a clear N-S trend (except possibly pectoral band), which might
have influenced him regarding the inclusion of clarisse, which does
not appear to differ strikingly in these respects, its chief claim to
difference seeming to be a more rosy gorget. This arrangement was followed by
Meyer de Schauensee (1966) without comment, as well as by Meyer de Schauensee
& Phelps (1969) and Hilty & Brown (1986). In the meantime, Phelps &
Phelps (1953) had described violiceps as a race of clarisse, from
the Serranía de Perijá on the Colombian-Venezuelan frontier but without
mentioning spencei although its gorget is more violaceous than that
of clarisse, perhaps approaching the latter (?).
The
next useful information was published by Fjeldså & Krabbe (1990), who
described the gorget of spencei as "violet, often with a
distinct coppery sheen, not strongly glistening" (the "different
texture" of Zimmer?) and noted similarities in the throat
color of females to that of mavors, males of which have an orange to
orange-green gorget. They also noted the "peculiar silvery-green"
frontlet of spencei, apparently unlike those of other members of
the group including clarisse and violiceps. They called the
enlarged amethysticollis of Zimmer a "megaspecies",
noting that clarisse had often been split in the past. Finally,
Schuchmann (1999) returned to the classification of Peters (1945), adducing as
reasons "subtle morphological differences" (unspecified) and
"markedly disjunct range" (certainly the case) as "supporting
treatment as separate species", noting also that "spencei was
sometimes considered a separate species, especially when the races of (clarisse)
were lumped into amethysticollis". This treatment was followed
by Hilty (2003).
There
would seem to be no really clear-cut resolution to this problem, as much
depends upon what one takes to be the "status quo" (or starting
point). Although it was evident that the group was probably oversplit, the
lumping of Peters was done without explicit rationale. Zimmer was explicit on
several points (such as excluding spencei) but similarly gave no
reasons for considering clarisse a subspecies of amethysticollis.
Finally, Schuchmann gave no clear morphological reasons (the differences
between all these forms are more or less "subtle") for returning to
the arrangement of Peters, the only clear argument being distribution: the
obvious division into northern and southern groups, separated by a gap. My
reading of Fjeldså & Krabbe leads me to question the lumping of at
least spencei with the others since they implicitly raise the
possibility that it might be closer to mavors based upon female
plumage and the "coppery sheen" of the male's gorget, which also
might be the motive for Zimmer's citing of differences in color and texture of
its gorget. This is a lot of "might be's",
but in the context of the generally vague descriptions of most plumages, this
could justify maintaining this form as a species, pending future study. More
problematic is what to do with clarisse -- follow Zimmer in
lumping it with amethysticollis, or follow Schuchmann (in part) in
separating it (based largely on distribution, also a whiter pectoral bar and
rosier gorget -- features that I am not wholly convinced are of specific value
given their variation among the S races -- and there is N-S trend -- white to
buffy -- in the pectoral bar, if not in other characters). Hence, I consider
that the weight of evidence, such as it is, favors maintaining the Zimmer-Meyer
de Schauensee arrangement for the present and suggest (not very strongly) a NO
vote on this proposal, while emphasizing that a careful analysis citing explicitly
all characters is sadly lacking and that genetic data also could be helpful (at
least regarding a possible relationship of spencei with mavors).
I could easily be persuaded to change my mind, particularly regarding clarisse,
were a careful study to appear.
Literature
Cited:
Cory 1918, Catalogue of
Birds of the Americas, vol. II, part 1.
Chapman 1926,
Distribution of Bird-Life in Ecuador, Bull. AMNH vol. 55.
Peters 1945, Checklist
of Birds of the World, vol. 5.
ZIMMER, J. 1951.
Studies of Peruvian birds, No. 61. The genera Aglaeactis, Lafresnaya,
Pterophanes, Boissonneaua, Heliangelus, Eriocnemis, Haplophaedia, Ocreatus,
and Lesbia. American Museum Novitates 1540: 1-55.
Phelps & Phelps Jr.
1953, Proc. Biol. Soc. Wash. 66:1-12.
Meyer de Schauensee
1966, Species of birds of South America
Phelps & Meyer de
Schauensee 1969, Guide to the birds of Venezuela
Hilty & Brown 1986,
Guide to the birds of Colombia
Fjeldså & Krabbe
1990, Birds of the High Andes
Schuchmann 1999, HBW
vol. 5.
Hilty 2003, Guide to
the birds of Venezuela ("second edition")
Gary Stiles, November
2004
_____________________________________________________________________________________
Comments
from Remsen:
"NO, but like Gary, with little conviction. Neither classification
provides convincing rationale, so I'll go with status quo until that latter is
provided."
Comments
from Robbins:
"NO. Based on what is now available any decision would be arbitrary, thus
I support the 'status quo'."
Comments
from Pacheco:
"NO. Diante da complexidade
do presente caso, é preferível continuar com o tratamento proposto por Zimmer
(1951); porquanto, este ainda seja a única revisão do grupo
(parafraseando Stiles) seriamente apresentada."
Comments
from Jaramillo:
"NO. More work needed on this front. My guess is that more than
one species is involved, but the division would seem to be arbitrary at the
moment."
Comments
from Nores:
"NO; pienso que las diferencias de plumajes son sólo
subespecíficas y que el argumento indicado por Schuchmann en varias
oportunidades 'markedly disjunct range o disjunct range' para
separar especies es más un fundamento para considerarlas subespecies que
especies."
Comments
from Zimmer:
"NO. This seems like a case where more data is needed. Any decision on
where to split at this point seems arbitrary."