Proposal (954) to South
American Classification Committee
Recognize minuta
Bonaparte as the second species in the genus Nyctiprogne
Proposal
673 advocated splitting Nyctiprogne
leucopyga into two species, based mainly on the genetic data of Sigurdsson
& Cracraft (2014); the name given for the second species was N. latifasciata. The proposal was accepted by SACC. However,
the discussions regarding the split disclosed several underlying problems. To
begin with, the distributions of the two species were very incompletely known;
no clear differences in plumage or morphology were available (beyond the
impression that these are “subtle”). Likewise, apparent differences in
vocalizations were mentioned but not tied to specific specimen evidence or
details on localities. Finally, based on examination of the illustration of N. leucopyga in Spix (1825) and the
description of latifasciata by
Friedmann (1945), Piacentini concluded that the latter was indistinguishable
from nominate leucopyga and therefore is a synonym of leucopyga, thus leaving the second species without a name. Shortly
after this, the committee received a communication from Nigel Cleere (in press)
that presented an apparently satisfactory nomenclatural resolution. He
presented detailed information on morphology and distributions that clarify the
recognition of the two species, confirming Piacentini’s judgment that latifasciata is a synonym of leucopyga, and stated that the second
species should be known as N. minuta Bonaparte
1850, and that the additional subspecies described since then pertain to minuta, also giving more details on
their ranges and distributions. Upon applying Cleere’s criteria to a small
series of Nyctiprogne in the collection of the Instituto de Ciencias
Naturales of the Universidad Nacional de Colombia, I found that both
species occur in Colombia: two specimens from Mitú, Vaupés are clearly leucopyga, while one from Arauca, two
from Casanare, plus a recording that I made from western Meta are clearly minuta. However, because the name minuta
had been proposed by Bonaparte
(1850) with virtually no supporting details, its applicability appeared
definitely questionable. Doubts in this regard were voiced by several committee
members, such that SACC tabled the acceptance of this proposal pending
resolution of the nomenclature.
After several attempts to contact Nigel Cleere for
more details, I recently received his reply, which I believe will serve to
definitively resolve these doubts. Cleere provided a reference to the
typification of Bonaparte´s (1850) Caprimulgus minuta: Holotype
RMNH 88413, adult male, Brazil: type specimen specified by van den Hoek Ostende, L.W., Dekker,
R.W.R.J. & Keijl, G.O. 1997, p. 163 in: Type-specimens of birds in
the National Museum of Natural History, Leiden. Part 1. Non – Passerines. Nationaal
Natuurhistorisch Museum Leiden, Technical Bulletin 1, 248 pp. These authors
noted that Bonaparte had spent a year in the Leiden museum, putting his new
names on many specimens for which no published names existed, although there
were various unpublished manuscript names by Temminck and Natterer (part of his
rush to complete his Conspectus before dying, as his terminal illness was
becoming more severe: the last version of the Conspectus actually ends with an
incomplete generic description!) have seen the van den Hoek et al. publication,
which validated Bonaparte’s name and established its type. Cleere personally examined this specimen and
confirmed its identification as minuta.
I sent voting members the text supplied by
Cleere (to appear in his revision of his book on Nightjars of the World,
apparently still in press) with further details regarding the two species of Nyctiprogne
(for inspection by SACC members only at Cleere’s request).
If the proposal passes, I will do a follow-up
proposal on English names.
F. Gary Stiles,
December 2022
Comments
from Robbins:
“YES. Kudos to
Gary and Nigel for clarifying all of this. As a result of their efforts, I vote yes for
recognizing minuta as a species.”
Comments from Areta: “YES. OK, now this is looking
much better than before. I am glad that SACC did not accept the usage of
latifascia before for
what has now been shown to be Nyctiprogne
minuta. It would make me feel much more comfortable if Cleere´s work was
published first, in the interest of full public disclosure of the features that
distinguish minuta
from leucopyga, and with
an available photograph of the type of minuta. BUT,
given Gary´s successful test of the features in museum specimens based on
features in the name-bearing type of minuta, I will
accept the notion that N. minuta
is the valid name for this nighthawk species."
Comments from Claramunt: “NO. I am still a bit
confused. I would like to see the evidence more clearly. Cleere describes leucopyga
as having white patches at either side of the throat but the type of leucopyga
illustrated by Spix conspicuously lacks such patches:
https://www.biodiversitylibrary.org/page/41278046#page/105/mode/1up
“Can the illustration in Cleere’s book be made available? Can we
wait until the evidence is published?”
Comments
from Bret Whitney (who has Remsen’s vote): “NO. Sigurdsson
and Cracraft (2014) stumbled into the realization that there are two
genetically distinct clades of nighthawks masquerading under the single name Nyctiprogne
leucopyga. Knowing little about these birds in life, or their distributions
beyond collecting localities of a few tissues, they applied, thanks to the
fabulous work of Friedmann (1945), the name leucopyga to one, and latifascia to the
other. Nomenclature, actual application of those names… well, that was 100%
“shot in the dark". Going back 20+ years, Whitney and Cohn-Haft had
independently identified two distinct song types inhabiting the same spaces on
river islands of the middle-lower Rio Negro in Brazil during the low-water
season when island substrates become accessible to these ground-nesting birds.
However, no definitive resolution of the nomenclature of these syntopic,
morphologically weakly differentiated species could be presented without first
making voice recordings of at least several individuals (what are levels of
vocal and plumage variation?) before collecting the birds, enabling a clearer
understanding of the identifications and widespread (and they are both
remarkably widespread) distributions of the two vocal types. That work has been
happening, in spurts, for years now, but there are some “loose ends” that those
of us involved with the work feel ought to be tidied up before presenting a
hypothesis of species limits and biogeographical relationships. Truth be told,
no genetic analysis was necessary for a two-species split based on recorded
specimens that could then be diagnosed morphologically, and matched to named
forms, or shown to be unnamed. Well…
maybe not. Because now, as the type of N. leucopyga is lost, we are left with an illustration accompanying the
original description on which to base the name — and the illustration certainly
appears to better match Friedmann’s (1945) N. l.
latifascia than any other, earlier
name. The type locality “Rio Amazonas,
Brazil” is useless. Accepting these realities, the name latifascia becomes a synonym of leucopyga, and the problem shifts, once again, to what name should
be applied to “the other” Nyctiprogne.
“Cleere (in press?) recommends that
Caprimulgus minutus (Bonaparte, 1850) is that
name. Although we do not yet have
sufficient data and analysis available for independent consideration, we do
have some material to work with. For example, in 2016, Thiago V. V. Costa sent
me photos of the type of minutus; it’s clearly a
Nyctiprogne, and the tail-band appears to be more medially
situated than is typical of leucopyga, which we
now understand (from the illustration of the type of
leucopyga) to be situated more proximally, nearer the
undertail coverts, along with other minor distinctions. Bonaparte’s
minutus has no locality beyond “Bresil”, which is useless, but
inconsequential, because the only result we really need to see is which clade
that specimen aligns with: “trillers" (= nominate) or “chunk-chewinkers”.
If it’s the latter, I would be accepting of the name minutus. If it’s in the triller clade, it’s likely
best considered another synonym of leucopyga, and we
have to dig deeper (more on that if it should come to that).
“So, where does that leave us, today? Not materially different from where it all started
30 years ago: we have two species-level
Nyctiprogne nighthawks, the names and distributions of
which are incompletely understood. How
is this situation resolved? It is most
adequately, and elegantly resolved by a combination of a small amount of highly
focused vocal + collecting fieldwork (a great deal has already been done),
followed by genetic analysis of all specimens collected after voice recording,
together with — ideally — analysis of toe-scrapes of all extant type specimens
in the genus. At the very least, it’s
critically important to obtain a sufficient DNA yield from the type of
minutus to confidently place it in the phylogeny.
“To those who wring their hands that, by following the above,
recommended course of actions, we would be choosing to wait for an adequate
(but who-knows-when? soon, we expect!) analysis of the situation rather than
move ahead with recognition of two species and fix (the almost inevitable)
problems with nomenclature down the line... I would offer that it’s best to
calm down and just pretend you don’t know there are two species of
Nyctiprogne, so there’s nothing to worry about. After all,
that’s pretty much exactly the way things would be at the moment if Sigurdsson
and Cracraft had not been supplied with tissues that glaringly revealed the
paraphyly of Nyctiprogne.”
Additional
comments from Stiles:
“Cleere provided a diagnosis of minuta vs. leucopyga
and a reference to the typification of minuta with an explanation of
Bonaparte´s names bestowed in Leiden, and examined this type and identified it
as minuta. I applied Cleere´s criteria for distinguishing minuta
from leucopyga and found that it works, permitting me to identify both
species in Colombia. So, it´s not quite true that nothing has changed in the
last 30 years ago, as Bret laments! Looking through the literature, I found that
minuta had not been applied to any other Nyctiprogne - and if Nyctiprogne
remains a recognized genus, anything like a Caprimulgus minuta becomes a
non-starter.”
Comments from Del-Rio: “YES. Thanks Gary and
Nigel!”
Comments from Bonaccorso: “NO. It would be important to
revisit these arguments based on published data. If we accept this proposal, as
it is, we would then also have to accept, for example,
Nacho´s claims about not recognizing S.
iberaensis because it might be
S. melanops.”
Comments from Lane: “NO. I don’t understand the need
to deal with this before the publications in question are even published; this
is a recipe for error. Bret has made some comments above that seem to suggest
we pump the brakes here a bit, and I’m inclined to agree. From what I can
understand from the proposal and from follow-up comments here, I see that two
names are applied to two genetic lineages, but what does that mean? We have no
distributional handle for them, nor do we know which vocalization type is
represented by which name. This complex is a confusing one, and it would make
me feel better if the situation was laid out plainly so that there was no
question which name is applied to which group. So between these concerns, I
believe we should just wait for the Cleere publication to be published, and
perhaps for better definitions of the taxa to which these names are applied.”