Proposal (770) to South American Classification Committee
Treat Megascops colombianus as
a subspecies of M. ingens
Effect
on AOU SACC classification: Megascops
colombianus would return to former status as a subspecies of M. ingens.
Background: From the SACC footnote
under the name M. colombianus:
Megascops
columbianus was formerly (e.g., Meyer de Schauensee 1970) considered a
subspecies of M. ingens, but see Fitzpatrick
& O'Neill (1986) for recognition as a separate species; this treatment was
followed by Marks et al. (1999), but not Ridgely & Greenfield (2001). They
form a superspecies. Proposal needed for
continued recognition of this species.
Fitzpatrick
and O’Neill (1986) argued that morphological differences (wing length, tarsus
length, and amount of unfeathered tarsus) were sufficient to consider M. colombianus a species apart from M. ingens. Furthermore, they suggested
that M. colombianus was sister to
their newly described M. petersoni.
As mentioned in the above note, some more recent authors have reverted to the
original taxonomy, returning colombianus
to M. ingens.
New
information: Dantas et al. (2016) provided a phylogenetic
hypothesis that showed that the sister relationship proposed by Fitzpatrick and
O’Neill (1986) was incorrect, and that M.
ingens and colombianus were
indeed sisters, and not in the same clade as M. petersoni. Furthermore, Krabbe (2017) showed, through vocal
analysis, that there were no strong differences in voice between ingens and colombianus. He concluded:
“Likewise,
there do not appear to be vocal differences between M. [ingens] colombianus and M.
i. ingens. Differences between them in size, general hue, tail/tarsus
proportions and tarsal feathering (Fitzpatrick & O’Neill 1986) leave little
doubt as to the validity of the taxon colombianus,
but vocally there is no support for ranking it as a species.”
Analysis and recommendation: I am strongly convinced that Krabbe’s
recommendation is the correct one. I recommend a YES vote to returning colombianus to M. ingens.
Literature
cited:
Dantas, S. M., J. D. Weckstein, J. M. Bates, N. K. Krabbe, C. D. Cadena,
M. B. Robbins, E. Valderrama, and A. Aleixo. 2016. Molecular systematics of the new world screech-owls (Megascops: Aves, Strigidae):
biogeographic and taxonomic implications. Molecular Phylogenetics and Evolution
94:626-634.
Fitzpatrick,
J. W., and J. P. O’Neill. 1986. Otus petersoni, a new screech-owl from the eastern Andes,
with systematic notes on O. colombianus
and O. ingens. Wilson Bulletin 98:
l-14.
__________________________________________________________
Comments
from Stiles:
"YES. New genetic evidence and
vocal similarity (to which I can attest, having heard both) support subspecies
status for columbianus."
Comments
from Robbins:
"YES. Given that genetic data indicate that Megascops colombianus is sister to M. ingens, and vocal analyses by Niels
Krabbe demonstrated that they are very similar, it seems best to treat colombianus as a subspecies of ingens."
Comments from Zimmer:
“YES. I’m convinced that vocal
similarities/differences are the keys to species-limits in screech-owls,
trumping any apparent morphological similarities/differences until and unless
genetic data tell us otherwise. In this
case, recent genetic analysis supports the vocal analysis of Krabbe, so
treating colombianus as a subspecies
of ingens seems to be the way to go.”
Comments from Remsen:
“YES. Genetic and vocal data strongly indicate
subspecies rank for this taxon.”
Comments from Stotz: “YES. Lack of vocal distinctiveness makes it clear
that colombianus should be lumped
back into ingens.”
Comments
from Jaramillo:
“YES due to data on voice and genetics.”
Comments
from Claramunt:
“NO. If it is true that
they are different in “size, general hue, tail/tarsus proportions and tarsal
feathering”, whether they are similar or different in vocalizations is
immaterial. They seem to be two different birds. Vocalizations do not trump
every other piece of evidence, in my opinion.”
Comments
from Pacheco:
“YES. The data presented here are sufficient to comply with the recommendation
of this proposal.”