Proposal (656) to South American Classification Committee
Revise
the generic classification of 6 species of Hylophilus:
(A) resurrect Pachysylvia and (B)
recognize Tunchiornis
Effect
on SACC: This proposal would (A) transfer 5 species of
Hylophilus (decurtatus, hypoxanthus, muscicapinus, aurantiifrons, and semibrunneus)
to the resurrected genus Pachysylvia,
with a required change the ending of 4 of those specific epithets (to decurtata, hypoxantha, muscicapina,
and semibrunnea) to agree in gender
with Pachysylvia, and (B) transfer Hylophilus ochraceiceps to the newly
described genus Tunchiornis.
Background:
SACC
Vireonidae footnote 11 currently reads as follows:
11. Genetic data
indicate that Hylophilus is not monophyletic (Johnson et al. 1988) and
that at least three separate genera are required (Slager et al. 2014). SACC proposal needed <wait follow-up taxonomic paper by Slager
et al. > The name Pachysylvia was formerly (e.g., Ridgway
1904) used for Hylophilus.
Other lines of evidence besides
phylogenetics also support the polyphyly of Hylophilus. As Slager and Klicka (2014) wrote,
"[a]lthough Hylophilus species
do share some common anatomical proportions and plumage features, some striking
and concordant differences in habitat, voice, and iris color led Ridgely and
Tudor (1989) to posit that the genus might contain sufficient diversity to
warrant splitting into multiple genera."
Ridgely and Tudor (1989) categorized Hylophilus
into three groups: The pale-eyed
"scrub" group, the dark-eyed "canopy" group, and the
"understory" group (Hylophilus
ochraceiceps).
New Information:
Slager et al. (2014) produced a
phylogeny of Vireonidae using mitochondrial (ND2) and nuclear (3 Z-linked loci)
data that included 221 samples representing 46/52 currently recognized vireonid
species and 14/15 species of Hylophilus. The phylogeny of Slager et al. (2014)
showed that Hylophilus was
polyphyletic, composed of 4 clades spread throughout Vireonidae. The four clades are shown in phylogenetic
context in Figure 1 of Slager and Klicka (2014).
Analysis & Recommendation:
Hylophilus
is clearly polyphyletic based on molecular data (Slager et al. 2014) and four
genera are needed to reflect this diversity (Slager and Klicka 2014).
The first clade, containing Hylophilus sclateri, is addressed in a
separate SACC proposal.
The second clade, containing the
pale-eyed, scrub-dwelling species H.
poicilotis, H. amaurocephalus, H. flavipes, H. olivaceus, H. semicinereus, H.
thoracicus, H. pectoralis, and H.
brunneiceps, can remain in the genus Hylophilus
since the type species of Hylophilus
is H. poicilotis. See paragraph 5 of Slager and Klicka (2014)
for more discussion.
The third clade contains several
canopy-dwelling species with dark irides and complex songs: H. decurtatus, H. aurantiifrons, H.
hypoxanthus, H. muscicapinus, and
H. semibrunneus. Because Hylophilus
is in use for the "scrub" greenlets, these canopy species should be
transferred to the resurrected genus Pachysylvia
Bonaparte (type species = H. decurtatus),
which has priority. See 6th paragraph of
Slager and Klicka (2014) for more details. Since Pachysylvia
is feminine, the specific epithets for decurtatus,
hypoxanthus, muscicapinus, and semibrunneus
should be changed to decurtata, hypoxantha, muscicapina, and semibrunnea,
respectively.
The fourth clade, containing the forest
interior understory-dwelling Hylophilus
ochraceiceps, is sister to (Vireo
+ Hylophilus sclateri + Pachysylvia) and clearly needs its own
genus. Slager and Klicka (2014)
described Tunchiornis for this
purpose. See Slager and Klicka (2014)
paragraph 7 and page 2 for details.
Recommendation:
A YES vote is recommended on both, i.e.
(A) resurrect Pachysylvia, and (B)
recognize Tunchiornis.
Literature Cited:
Ridgely, R.S. &
Tudor, G. (1989) The Birds of South America. Vol. 1. The Oscine Passerines.
University of Texas Press, Austin, Texas, 596 pp.
Slager, D.L., Battey,
C.J., Bryson, R.W. Jr., Voelker, G., & Klicka J. (2014) A multilocus
phylogeny of a major New World avian radiation: The Vireonidae. Molecular
Phylogenetics and Evolution 80, 95-104.
Slager, D.L. & J.
Klicka. (2014). Polyphyly of Hylophilus and a new genus for the
Tawny-crowned Greenlet (Aves: Passeriformes: Vireonidae). Zootaxa
3884:194-196.
Dave Slager, November 2014
_________________________________________________________________
Comments
from Stiles: “YES to A
and B. The canopy greenlets form a
coherent group, with Pachysylvia
available as the genus name. Clearly ochraceiceps also requires its own genus
given its remote phylogenetic position.”
Comments
from Nores: “A-B: NO. I would include H. ochraceiceps, “canopy”
Hylophilus, and Hylophilus sclateri within
Vireo.”
Comments
from Zimmer: “YES to A
and B. The genetic data are clear that Hylophilus, as currently constituted, is
polyphyletic. The proposed
reclassification would appropriately recognize the two internally coherent
groups of pale-eyed (scrub greenlets) versus dark-eyed (canopy greenlets) in
separate genera (while employing historically used names), while placing the
very different, polytypic ochraceiceps
in its own, newly erected genus.”
Comments from Robbins: “YES to both.
Genetic data make this a straightforward decision for erecting two genera for
the clades that clearly are not monophyletic with true Hylophilus vireos.”
Comments from Areta: “YES to A and B. Taxon sampling is
excellent, and the phylogenetic grouping of the Pachysylvia should be recognized at the genus level. I also agree
in that the very distinctive and phylogenetically isolated ochraceiceps deserves to be in its own genus. Tunchiornis is a fine name.”