Proposal (987) to South
American Classification Committee
Establish English names for Nesotriccus
murinus complex
SACC
proposal 956 passed to treat the Mouse-colored Tyrannulet
(then Phaeomyias murina, now Nesotriccus murinus) as consisting
of three species: (1) the widespread murinus group of subspecies, and
two peripheral taxa (2) tumbezana (with inflava) of the Pacific
coast of NW South America, and (3) maranonicus, endemic to the Marañon
region. We voted not to recognize a
fourth species, incomta (with eremonoma) pending publication
of additional data on vocalizations and a possible problem in nomenclature in
terms of which names apply to which taxa; see Nacho’s Discussion section in 956. But it is important for us to anticipate this
possible future split in choosing English names.
I had previously asked for someone to write a proposal on
names for the new and potentially new species.
No takers. Then, I just asked for
feedback on whether to go with short names or compound names, and the only
response I got was from David Donsker.
So, it is clear no one wanted to tackle this situation for reasons
obvious below.
Simplified distributions of the 4 groups are as follows:
1. incomtus (with eremonomus): W. Panama to
northern and eastern Colombia, NE Ecuador, N Venezuela, the Guianas, and Trinidad.
2. murinus (with wagae):
everything south of incomta south to S Bolivia, Paraguay, N Argentina,
and SE Brazil.
3. tumbezanus (with inflavus):
SW Ecuador and NW Peru to Lambayeque.
4. maranonicus: Marañon.
These taxa have only weak plumage differences – as in many
small tyrannids, it’s the voice that really distinguished them other than
range. So, plumage-based names would
seem to be out. The species tumbezanus and maranonicus,
therefore by default, should probably be modified by Tumbes/Tumbesian and
Marañon, respectively. Not very
inspiring, but if anyone has any better ideas, speak up. I haven’t researched this extensively, but
the English names in the literature that I can find are in Cory & Hellmayr
(1927): “Mouse-colored Tyrannulet” for nominate murinus,
“Waga’s Tyrannulet” for wagae, “Northern
Mouse-colored Tyrannulet” for incomtus, “Tumbez Tyrannulet”
for tumbezanus, and “Chapman’s
Tyrannulet” for inflavus. The
other taxa were not yet described. Also,
Ridgely & Greenfield (2001, Birds of Ecuador) already treated tumbezanus
as a separate species based on voice and called it Tumbesian Tyrannulet, and
this was followed by the IOC lists, which also treated maranonicus as a
separate species “Marañón Tyrannulet” as well as incomtus as “Northern
Mouse-colored Tyrannulet” and designating murinus as “Southern
Mouse-colored Tyrannulet”. This
classification, which was also followed by eBird/Clemens without waiting for
SACC or NACC to endorse the splits. (And
as it turns out we have rejected treating incomtus as a separate species
for lack of published data, as explained in SACC 956.)
Tangentially,
beyond our area, Nesotriccus has always been called “Cocos Flycatcher”,
but now that we know it is embedded in a group called “Tyrannulets”, I would
recommend that NACC consider a switch to “Cocos Tyrannulet.” The key ingredient of the name is Cocos, not
“Flycatcher”, which applies to dozens of tyrannid genera. A change to “Tyrannulet” would signal that Nesotriccus
is no longer a monotypic genus, and would make its last name consistent with
other members of the expanded genera. I
normally favor stability, but in this case I favor drawing attention to a
change in classification by flagging it with a partially new name. But that’s not a SACC issue.
The
Ridgely-IOC-eBird names are ok, but I think it’s worth at least considering
adding “Mouse-colored” to the names of Tumbesian and Marañon to identify them
as congeners and separate them from the other ca. 59 species in 12 genera with
the “last name” of just plain “Tyrannulet.”
If we eventually split incomtus, as is already the case in two
major world classifications, we already have a long compound name if we follow
IOC etc. and go with “Northern Mouse-colored” and Southern Mouse-colored, why
not also go with Tumbesian Mouse-colored and Marañon Mouse-colored to set off
the group? But that’s not a problem if
and until we split up the murinus group.
For now, just “Mouse-colored Tyrannulet” is just fine for N. murinus,
and retaining that well-established parental name for the by-far most widely
distributed and familiar species of the trio.
So,
I recommend we go with:
Mouse-colored
Tyrannulet (N. murinus)
Tumbesian Tyrannulet (N.
tumbezanus)
Marañon Tyrannulet (N.
maranonicus)
A
YES vote endorses these names. A NO vote is for something else – and please provide
alternatives.
Van Remsen, December
2023
Comments
from Jaramillo:
“YES
for these names:
Mouse-colored Tyrannulet (N. murinus)
Tumbesian Tyrannulet (N. tumbezanus)
Marañon Tyrannulet (N. maranonicus)”
Comments
from Gary Rosenberg (voting for Remsen): “YES.
“In the name of stability, I think adopting “Tumbesian” for
tumbezanus and Marañon for maranonicus
makes sense, especially given this is how the IOC currently treats
the two forms. Ridgely treated the two under “Tumbesian” - and given that they
are now split, retaining Tumbesian for the one that is mainly found coastally
in the Tumbes Region makes total sense. I vote yes for “Marañon” as well -
especially given that the Latin name is “maranonicus” - so that
makes sense - and that is what the IOC calls it - so a one for unification and
stability! I do note, however, that a portion of the population are found
outside of the Marañon proper - but I guess you can say that those locations
are technically in the overall Marañon drainage.
“I do not understand why eBird chose their own name for
tumbezanus creating “Tumbes” Tyrannulet - which is doubly
confusing since they also changed “Tumbes Tyrant” to Tumbes Chat-Tyrant.
Thankfully, the IOC has not adopted that change! I think it is a very bad idea
for the eBird team/Clements to go rogue and do their own bird naming - and not
following either the SACC or the IOC - all this does is add confusion and
created further destabilization in bird names.”
“I also vote YES to retain (for now) Mouse-colored Tyrannulet.
“I would be in favor of adding “Mouse-colored Tyrannulet” to both
Tumbesian and Marañon to further distinguish this group of tyrannulets - which
would certainly be helpful for learning purposes - allowing people to focus on
this rather unique group of tyrannulets as a group - I am all in favor of
making tyrannulet identification easier for birders and scientists alike.”
Comments
from Zimmer:
“YES to
the English names suggested inn Proposal 987 for the splits in the Nesotriccus
murinus complex: Mouse-colored Tyrannulet (N. murinus); Tumbesian
Tyrannulet (N. tumbezanus); and Marañon Tyrannulet (N. maranonicus).
And, for what it’s worth, I would agree with going to the long compound names
(Northern, Southern, Tumbesian and Marañon Mouse-colored Tyrannulets) if and
when incomtus
is split.”
Comments from Donsker (voting for Areta): “I vote
YES for
Proposal 987 establishing English names for the splits of
the N. murinus
complex.
“That is:
Mouse-colored Tyrannulet (N. murinus)
Tumbesian Tyrannulet (N. tumbezanus)
Marañon Tyrannulet (N. maranonicus)”
Comments from Steve Hilty (voting for Bonaccorso): “I am
fine with the following, but personally I would choose the longer versions (see
discussion below):
Mouse-colored Tyrannulet, N.
murinus
Tumbesian Tyrannulet, N.
tumbezanus
Marañon Tyrannulet, N.
maranonicus
“As noted by a couple people, I think it would be helpful to
incorporate the original name, Mouse-colored" into these new names as you
also mentioned. This helps preserve some of the history of the taxonomy—and for
the "lay person" that doesn't think about these names and all of
these convoluted taxonomic twists and turns every day, but still tries to
maintain control of a personal list—I think the longer names provide several
advantages (a geographical clue; a taxonomic clue; and a window into historical
decisions).
“Frankly, for those of us close to these names and the associated
taxonomy, it is easy to forget that the primary users of these names are
non-professional ornithologists, and the more information a name contains, the
more useful it is to most people. The length of the name is, in most cases,
irrelevant. We have been living with and using numerous 4- and 5-word English
bird names for years without issue or objection.
“In cases where several similar species are involved, I find
longer names preferable because they convey more information than abbreviated
names, and especially if they incorporate geographical or behavioral
attributes. As an aside, shortened names that rely heavily on descriptive
colors—rufous-crowned, rufous-browed, rufous capped, rufous-fronted, and so on
ad nauseam often
quickly become confusing, especially in field use.
“Thus, these below would be my first choice:
Mouse-colored Tyrannulet,
N murinus
Tumbesian Mouse-colored Tyrannulet,
N. tumbezanus
Marañon Mouse-colored Tyrannulet,
N. maranonicus
“And in the likelihood that the north-south split occurs (voice
and some plumage differences are certainly apparent), why not use (as you
suggest):
Northern Mouse-colored Tyrannulet
Southern mouse-colored Tyrannulet”
Comments from Josh Beck (voting for Claramunt): “YES on
this proposal. One comment: Tumbesian is preferable to Tumbes as noted by Gary
to avoid confusion. However, if Mouse-colored is kept in the names, Tumbes
Mouse-colored Tyrannulet might be preferable to Tumbesian Mouse-colored
Tyrannulet based upon syllable count. I’m mildly in favor of keeping
Mouse-colored in the names due to the use (already by eBird/Cornell and perhaps
likely in the future by others) of Northern and Southern Mouse-colored
Tyrannulets when treating incomtus as separate from murinus.”
Comments from Lane: “YES to Mouse-colored Tyrannulet
(N. murinus), Tumbesian Tyrannulet (N. tumbezanus), and Marañon
Tyrannulet (N. maranonicus). Unless we consider added
"Mouse-colored" to the name of Cocos Island Flycatcher, I don't think
it's necessary to use it in the names of N. tumbezanus or N.
maranonicus. In comparison to the core N. murinus group, both of these
western forms are actually quite distinctive in appearance and (especially!)
voice, so it doesn't phase me to not maintain the link between them and their
"Mouse-colored" origin. If/when N. murinus is split up, we can
decide then if it is imperative to maintain "Mouse-colored" in the
daughter species' names... for now, I'm still waiting to see how that shakes
out before I worry about names.”
Comments from Stiles: “On this one, I find the proposed
names acceptable (Mouse-colored, Tumbesian (I prefer this to Tumbes as it makes
it more clear that a particular zoogeographical region is involved) and Marañón
(for much the same logic). If and when the incomtus-murinus split
is published and accepted, I am persuaded by Steve's view that the E-names of N
and S M-c T would be the most logical way to go - and that adding M-c to the
names of Marañon and Tumbesian would also be appropriate in relating the split
to the previous, un-split situation of everything in murinus. Given the
relatively wide distributions of both murinus and incomtus, I
think that finding more appropriate distribution-based names for these would be
difficult - and the overall phenotypic similarity of all 5 taxa (which do
represent a distinct little clade) best expresses their relatedness.”