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THE WILSON JOURNAL OF ORNITHOLOGY • Vol. 123. No. 3. September 2011 
from caudatus also apply, namely that the sides of 
the head arc eoncolorous with the crown, and, in 
their Latin diagnosis, that the bill is shorter. These 
points were repeated in English by Salvadori 
(1900), in an elaborate defense of species status 
for branickii which evidently became lost in time, 
and by Hellmayr and Conover (1948). 
The question of whether Theristicus branickii is 
a species is clearly tied to the question of its 
morphological distinctiveness. We sought to 
answer the latter through study of museum 
specimens, and answer the former by use of a 
new system for classifying taxa as species or 
subspecies based on phenotypic differences, 
which are allocated a score reflecting their 
perceived magnitude (Tobias et al. 2010). 
quantify effect sizes to discriminate thresholds 
of morphometric distinctiveness: we used an 
online calculator (http://www.uccs.edu/~faculty/ 
lbecker/) for these values. The scoring of plumage 
differences involves an assessment of characters 
which, although more qualitative because depen¬ 
dent on individual judgment, requires observance 
of an explicit set of criteria relating to shade, 
color, contrast and extent, and which thus 
"minimizes subjectivity and maximizes repeat¬ 
ability” (Tobias et al. 2010:733). However, these 
criteria do not mention how to score the presence 
or absence of a feature like a wattle; we equated it 
to the “presence of an entirely different pattern", 
which Tobias et al. (2010:733) indicate as a major 
difference. 
METHODS 
We examined and measured adult specimens of 
melanopis (31; 12 males, 11 females, 8 unsexed) 
and branickii (32; 15 males, 9 females, 8 unsexed) 
to ascertain the accuracy of the original descrip¬ 
tion and resolve the taxonomic status of branickii , 
conclusively, in the American Museum of Natural 
History, New York (AMNH), Natural History 
Museum. Tring, UK (NHM), Museum National 
d’Histoire Naturelle, Paris (MNHN). National 
Museum of Natural History, Washington, D.C. 
(USNM). and Zoologisches Museum Berlin 
(ZMB), and examined photographs of both taxa 
widely available online. Measurements taken (by 
NJC), using callipers and rulers, were: length of 
bill to skin on top of the culmen, tarsus length 
from top of the tarsometatarsal bone at the rear to 
the junction with the middle toe at the front, 
curved wing length from carpal bend to wing-tip, 
and tail length from tip to the point of insertion. 
Differences between the two taxa in plumage 
color and pattern were judged qualitatively by eye 
except the width of the upper belly-patch, which 
was measured to the nearest 5 mm. 
Tobias et al. (2010) introduced a quantitative 
system for measuring phenotypic differences 
between lower taxa based on four categories of 
distinctiveness, each with a simple numerical 
score for both morphometric and plumage char¬ 
acters: minor (score 1), medium (2), major (3), 
and exceptional (4). The scores for the two 
greatest uncorrelated morphometric differei 
and three strongest plumage differences 
summed, and taxa are treated as species if t 
overall score reaches seven. Tobias et al (21 
recommended use of Cohen’s d statistics 
RESULTS 
We found the mensural differences striking 
(Table 1). The bill of branickii is generally much 
shorter, the legs somewhat shorter, the wing- 
length longer (there is considerable overlap), and 
the tail notably longer. There was little overlap in 
bill or leg length in our sample, and only the 
slightest overlap (the same value, scored once 
each) in tail length. We also observed, based on 
skins and photographs, although not measurable, 
that the neck of branickii appears distinctly 
shorter than in melanopis. 
Some seasonal change in the intensity of the 
rich rufous-chestnut on the face of branickii is 
apparent, and also in the intensity of the buffy- 
rufous of the neck. Certain features, however, are 
consistent in all specimens and photographs: 
(1) branickii has the rufous-chestnut of the 
crown continuing smudgily onto the face 
and back to a broad area of the upper neck: 
melanopis shows a clear, clean division 
between the (generally rather paler) rufous- 
chestnut crown and the lower face, the 
dividing line running behind the eye and 
tapering onto the nape (rather than spreading 
over the upper neck) (medium difference: 
score 2): 
(2) branickii shows short lines of bare black skin 
on the submoustachial and malar area and a 
fully feathered chin and throat; melanopis 
possesses a black semi-circular mesial chin 
wattle (major difference: 3); 
(3) branickii has a white belly-patch between the 
gray breast-line and the black underbelly- 
while the equivalent in melanopis is rusty- 
