Proposal (403) to South
American Classification Committee
Elevate Pyrrhura
griseipectus to species rank
Effect on South American CL: this would recognize P. griseipectus as distinct from P.
leucotis, overriding part of Proposal #306.
Background: SACC has recently reviewed the status of several Pyrrhura of the picta-leucotis group
based on genetic analysis of mtDNA by Ribas et al. Among the results was the
downgrading of P. griseipectus to a subspecies of P. leucotis
based on SACC considering them closely related because they were not
reciprocally monophyletic in the mitochondrial DNA analysis, "similar in
plumage, and more or less weakly differentiated ecologically".
Reassessment of available information: SACC adopts the biological species
concept, which we all acknowledge to be problematical and vulnerable to
subjective assessments. Also, we think that the differences between P.
leucotis and P. griseipectus should have been described in better
detail for a proper evaluation. This may have affected judging the status of Pyrrhura
griseipectus.
Full species status for P. griseipectus
can be argued based on the following:
1 - Sorting lineages from the evidence in Ribas et al (2006) is problematical
and, although reciprocal monophyly is desirable, this is not a determining
condition to consider an allopatric taxon as part of another. Care should be
taken in such analysis, since recent work on Monarcha flycatchers (and other taxa) has shown that very small
genetic differences may be sufficient to promote speciation. It should also be
mentioned all specimens of leucotis and griseipectus used in the
analysis were captive and the risk of hybridization in such conditions is not
beyond doubt.
2 - P. griseipectus shows diagnosable plumage characters from P.
leucotis or P. pfrimeri summarized by Olmos et al. 1998, 2005,
and further elaborated here:
a - Head color: leucotis
has a blue suffusion on the forehead (sometimes extending to above the eyes),
nape and sides of the neck, the rest of the head being buffy-gray; griseipectus
only has the blue suffusion on the sides of the neck, the crown being entirely
grey.
b - Auricular patch:
cream to yellowish in leucotis, most birds showing a buff tinge; pure
white to cream, and notably larger, in griseipectus. In the latter the
ear-patch connects with the pale breast (see photos of live birds below).


c - Eyering: dark
blue in leucotis; variable, ranging from whitish to slaty in griseipectus.
d - Breast feathers:
in leucotis these are green with a blue suffusion, more intense near the
neck, and with a broad pale grey or buff subterminal band and black terminal
one; in griseipectus the breast feathers are dusky grey with a broad
cream to pale buff terminal band.
These color differences result in strikingly different birds, no overlap in
character condition being noticeable in the specimens we have studied either in
collections or in the field. Photos of specimens showing the breast pattern are
attached. See also the following for photos of live free-living P.
griseipectus and P. leucotis.
Pyrrhura griseipectus:
http://farm3.static.flickr.com/2526/3721048452_a07a76ab5d_o.jpg
http://farm1.static.flickr.com/78/220557854_bd27b9ec6c_o.jpg
http://farm4.static.flickr.com/3234/3064136225_2c613eb16c_o.jpg
Pyrrhura leucotis:
http://farm3.static.flickr.com/2655/3720173909_e90c138870_o.jpg
http://www.wikiaves.com.br/foto.php?f=4531&t=s&s=438
http://www.wikiaves.com.br/foto.php?f=888&t=s&s=438&p=1
3 - Besides color differences, P. griseipectus has a significantly
longer bill and broader and deeper mandible (Olmos et al. 1998). This
results in a more robust bill and the birds looking distinctly larger-headed compared to leucotis, which certainly reflects
ecological differences. These are also evident in the different habitats and
ecological and biogeographical settings in which the taxa live.
4 - P. leucotis is a bird of the lowland Atlantic forest from southern
Bahia to Rio de Janeiro (which might be considered as a discreet endemism
center defined by species such as Cotinga maculata), whereas P.
griseipectus is restricted to montane forest enclaves that have strong
Amazonian affinities in otherwise semi-arid Cear‡ and Pernambuco.
In between there are thousands of kms that include a whole endemism center
devoid of any Pyrrhura (the Pernambuco Center) despite the presence of
Atlantic forest, which should have a taxon of the group, and the area from
Bahia de Todos os Santos to the mouth of the S‹o Francisco river, which some might consider a discrete subcenter based on endemic taxa such as Pyriglena atra. So, from
a biogeographical standpoint, P. griseipectus is a quite particular
entity that should be considered distinctive from P. leucotis.
5 - Although the information on vocal differences between the taxa is as
yet unpublished, the 'song' of P. leucotis and P. griseipectus
shows diagnosable differences allowing one to tell them apart based on
vocalizations only, with that of griseipectus being of a higher
frequency compared to leucotis.
This difference can be appreciated in the attached sound file, sonogram, and
the table below:
|
|
1¡ peak |
2¡ peak |
|
|
Hz |
Hz |
|
P. griseipectus #1 |
1913 |
3757 |
|
|
2031 |
4050 |
|
|
1971 |
4050 |
|
|
2031 |
4111 |
|
|
1857 |
3872 |
|
|
1857 |
3814 |
|
|
1942 |
3872 |
|
|
2001 |
3989 |
|
|
2125 |
4050 |
|
|
2031 |
3989 |
|
|
2001 |
3989 |
|
|
2093 |
4111 |
|
|
1971 |
3989 |
|
|
|
|
|
Mean |
1986 |
3973 |
|
SD |
81 |
112 |
|
|
|
|
|
P. leucotis #2 |
1760 |
3520 |
|
|
1857 |
3814 |
|
|
1748 |
3234 |
|
|
1697 |
3434 |
|
|
1748 |
3332 |
|
|
|
|
|
Mean |
1762 |
3467 |
|
SD |
58 |
222 |
Recommendation:
The available evidence is enough to consider P. griseipectus a full
species distinctive from P. leucotis (and other species of the group).
Morphologically it shows both plumage, and structural differences rendering it
perfectly diagnosable (with no character overlap) from any other taxa in the
group, including P. leucotis. It is restricted to a particular habitat
with distinctive biogeographical history, being quite isolated from P.
leucotis. Vocal evidence, although in need of further study, shows
further differences between P. griseipectus and P. leucotis.
Literature cited
Olmos, F., P. Martuscelli, and R. Silva e. Silva. 1998. Ecology
and habitat of Pfrimer's Conure Pyrrhura pfrimeri, with a reappraisal of
Brazilian Pyrrhura leucotis.
Ornitolog’a Neotropical 8: 121-132.
Olmos, F., W. A. G. Silva & C. Albano. 2005.
Grey-breasted Conure Pyrrhura griseipectus, an overlooked
endangered species. Cotinga 24:
77-83.
Ribas, C. C., L. Joseph, and C. R. Miyaki. 2006. Molecular
systematics and patterns of diversification in Pyrrhura (Psittacidae)
with special reference to the picta-leucotis complex. Auk:123: 660-680.
Fabio Olmos, Ciro Albano, Alberto Campos, Weber Gir‹o, & Jeremy
Minns
July 2009
Comments from Zimmer:
ÒYES. Following are my comments
from the earlier massive Pyrrhura
proposal (#306) as regards DougÕs recommendations at that time for the
treatment of griseipectus and leucotis as conspecific: I disagree with Doug's recommendation on subproposal B. I agree that pfrimeri
is morphologically and ecologically more distinct from leucotis and griseipectus
than either is from one another. However, the morphological and ecological
differences between griseipectus and leucotis are at least on a
par with those between various members of the picta group that are here
being recognized as or recommended for separate species status. When this
yardstick is applied, in combination with the recognition of the formidable
disjunction between the ranges of griseipectus and leucotis -
which effectively means that the two forms are on independent evolutionary
trajectories - it seems that recognition as separate species is warranted. I am
not troubled by the lack of genetic evidence supporting this move - see Gary's
comments under Proposal #181, which nicely sum up the arguments against giving
too much weight to genetic evidence in matters of resolving species limits.Õ Ó
ÒI think that Fabio and his co-authors of
this proposal raise an interesting point in noting that the ranges of griseipectus and leucotis are separated by a large geographic area containing
Atlantic Forest and known to be a separate center of endemism (the Pernambuco
Center), which lacks any taxon representing this group of Pyrrhuras. This
complete disjunction really does suggest different biogeographical histories
for these birds. The biometric
differences in bill size certainly suggest different ecologies, and the vocal
differences, although still unpublished, present additional evidence. Again, we run into the problem that no
analysis presenting all of this data has been published, but IÕll go with my
earlier position on this until published evidence proves me wrong.Ó
Comments from Nores: ÒNO. En mi respuesta a la propuesta #181 yo puse: ÒPienso que las diferencias
de plumaje, genŽticas y de h‡bitat que existen son suficientes para separarlas,
especialmente a pfrimeri. No obstante, pienso que antes de tomar una
decisi—n ser’a importante consultarle a Ribas para que opine si griseipectus
y leucotis son especies diferentes, ya que Žl encontr— una estrecha relaci—n
entre estas dos especies." Ahora tenemos publicado el an‡lisis de Ribas et
al. (2006) donde griseipectus y leucotis est‡n juntos en un ÒcladeÓ bien
soportado y presentan distancias genŽticas bajas (0.5% para el citocromo b y 1.0% en la regi—n control entre
individuos de griseipectus y leucotis), lo cual ha sido indicado por
Ribas et al. como una divergencia reciente de los dos taxas. TambiŽn coincido con lo dicho por
Douglas en la propuesta #306 ÒThey are closely related, similar in plumage, and
more or less weakly differentiated ecologically. Olmos et al. described them as
more distinct morphologically than are leucotis and pfrimeri,
which personally I don't seeÓ Tampoco veo que la distancia que existe entre los
rangos de los dos taxas sea un factor tan importante para considerar a ambos
taxas especies. 700 km no parece una distancia tan grande para un loro y m‡s
cuando ambas zonas pueden haber estado unidas o muy cercanas durante per’odos
m‡s hœmedos que el presente. Hay much’simos ejemplos de subespecies separadas
por igual o mayor distancia.Ó
Comments from Robbins: ÒYES. After
reading KevinÕs earlier comments about morphological and ecological differences
between leucotis and griseipectus being on the same level as
those in the picta group, which we recognize as distinct species,
coupled with Olmos et al.Õs new comments, I support recognizing griseipectus
as a species.Ó
Comments from Jaramillo: ÒYES. A nice summary and convincing argument by Olmos et al. I appreciate the
comments by Kevin. Disjunctions like the one in this situation are an
interesting data point we donÕt tend to think about in as great detail as we do
about voice, appearance and such. However, from my southern cone perspective it
often is a real pointer of where to look for potential unresolved taxonomic
issues for me. There are several taxa in Chile-Argentina where the distribution
pattern alone suggests good biological species may be involved, let alone the
ecological differences of the isolates (Accipiter
bicolor chilensis, Megaceryle torquata stellata, etc.).Ó
Comments from Remsen: ÒYES, but with hesitation
given the unclear species boundaries in Pyrrhura
as a whole. My interpretation of
the arguments is that these two are Òas different Ó or more so as many other
taxa treated as species in the genus, although without a rigorous comparative
framework, this remains a qualitative assessment. I hope Olmos et al. will publish the sonograms – this
could launch an investigation of voices in the genus to see if these can be
used in delimiting species.Ó
Comments from Pacheco:
ÒYES. The
set of information submitted by Olmos and colleagues to support the
reconsideration of the taxonomic treatment for griseipectus is
persuasive. They are important, in my opinion, vocal differences and the
obvious disjunction in the distribution between the two forms involved.Ó
Comments from Bret
Whitney: ÒYes. I
echo Remsen on this one as concerns the Òas different as...Ó idea. As for the ÒecologicalÓ differences
cited by some of us, I really donÕt see any or many. This bird feeds on a wide variety of fruits ranging from
introduced plants to Cecropias (heavily on the latter, like all members of the
genus), nests in existing/natural tree cavities like all the rest, and flies
around and vocalizes like all the rest — it is simply an isolate of the picta radiation in the BaruritŽ of
Cear‡. I donÕt doubt that some
vocal differences could be teased out among these picta-types if worked over hard enough. Griseipectus has
undergone some modification primarily (I would argue) because it is genetically
isolated and small chunks that are isolated from larger blocks are going to
develop ÒdifferencesÓ more quickly.
In line with its conservative morphological and vocal distinctions, it
appears that genetic differentiation of griseipectus
is slight relative to the whole group, all of which probably indicates a recent
isolation. Nonetheless, recognizing the biogeographical patterns
characteristic of eastern Brazil, it is on an independent trajectory at this
point and will continue to evolve as an integral species would. Thus, I think it is more appropriate to
recognize it today as an integral species than as, for example, a subspecies
that ornithologists at some indeterminate moment in the future, after the
genetic transitions add up to a more divergent story, will reevaluate as one
thatÕs now Ògone far enoughÓ to be classified at the species level. The alternative to recognizing it as an
integral species is to call it an incipient species — but I think the
word ÒspeciesÓ is the best operative term in these cases of clear allopatry (no
very close relative abutting) with evidence of divergence among populations.Ó
Comments from Stiles: ÒYES.
Evidence from morphology, ecology, biogeography and vocalizations all point to
species status for griseipectus. I share VanÕs misgivings in that there
are a number of taxa in this group that might well be deserving of species
status as well, but for which similarly detailed analyses are lacking. However, given that these occur in
several different countries over a wide area, it seems unrealistic to expect a
global solution to this problem in the near future, so perhaps a piecemeal
approach on a case-by-case basis is the best one can hope for at present.Ó
Comments from Schulenberg: ÒYES. I twice earlier voted in favor of recognizing griseipectus as a
species (Proposals 181, 306B), and so just am sticking to my position.Ó