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AMAUROSPIZA IS A small and remarkably ho-
mogenous monophyletic genus of ve or six
species of uncertain afnities (Orr and Ray
1945). Morphologically, they are conservative
in shape and vary little in size. They are mid-
sized nches in which the adult males are all
dull dark gray washed to some extent with blue,
whereas females are varying shades of brown.
Amaurospiza is traditionally placed within
Emberizidae, following Oryzoborus in linear
sequences, but has been considered “very pos-
sibly a cardinal-grosbeak close to, or conspecic
with Passerina” (Paynter 1970). Their distribu-
tion is fragmented and scattered from México,
parts of Central America, Colombia, Ecuador,
Perú, Brazil, Uruguay and Argentina (Paynter
1970, Narosky and Yzurrieta 1987, Ridgely
and Gwynne 1989, Ridgely and Tudor 1989,
Howell and Webb 1995, Salinas, et al. 1998,
and Ridgely and Greeneld 2001), and now in
Venezuela. Cabanis rst described the genus in
1861. Amaurospiza is still poorly known, little is
understood of its distribution and habitat, and
even less of its habits. Variously described as
local (Howell and Webb 1995), rare (Rowley
1962), rare and local (Ridgely and Greeneld
2001), rare and very local (Wetmore et al. 1984),
irregularly distributed (Paynter 1970), and very
restricted (Slud 1964), Amaurospiza generally
keep to low cover in undergrowth or bamboo
thickets and are not easy to see by chance. Spiny
Guadua bamboo thickets are also formidable
obstacles to watching birds. It is not an easy
bird to identify when seen. Indeed it is likely
that eeting observations of an Amaurospiza in a
situation where it was not expected could result
in the belief one had probably seen a Blue-black
Grassquit (Volatinia jacarina), Indigo Bunting
(Passerina cyanea), grosbeak (Cyanocompsa spp.),
or a seed-nch (Oryzoborus spp.).
Blue Seedeaters are all associated to a greater
or lesser extent with bamboo (Ridgely and
Gwynne 1989, Stiles and Skutch 1989, Sick 1993,
Howell and Webb 1995, M. Lentino pers. obs.,
J. Lyons pers. comm.). It seems likely that they
are much more closely associated with bamboo
than the literature might indicate. Birds ob-
served and identied by birdwatchers in wood-
land are more likely to be individuals that are
transiting, possibly foraging, en route from one
bamboo area to another. The pattern of frag-
Abstract.—At regular intervals throughout 2001, a unit from the Phelps Ornithological
Collection assisted a biological survey along the Río Caroni in Venezuela, north and down-
stream of the Embalse de Guri. One of the expeditions was to Isla Carrizal at 07º54’N,
63º04’W, a large uninhabited island thickly covered with groves of spiney Guadua latiolia
and Ripidoclaus sp. bamboos, mixed with semideciduous forest and patches of savanna. On
two occasions, three specimens of an unknown blue seedeater (Amaurospiza) were collected.
Those were the rst records for an Amaurospiza for northern South America, and subsequent
investigation showed it to be a hitherto undescribed taxon. Received 20 May 2002, accepted 26
May 2003
RESUMEN.—A intervalos regulares durante 2001, un grupo de la Colección Ornitológica
Phelps participó en un inventario biológico a lo largo del Río Caroní, en dirección norte y
aguas abajo del Embalse de Guri, Venezuela. Una de las expediciones fue a la isla Carrizal
(07º54’N, 63º04’W), una isla grande y deshabitada cubierta por rodales de bambúes espinosos
Guadua latiolia y Ripidoclaus sp entremezclados con bosques semicaducifolios y parches de
sabana. En dos ocasiones se colectaron tres especímenes de un semillero desconocido de color
azul (Amaurospiza). Estos especímenes representaron los primeros registros de un Amaurospiza
para el norte de Sur América, e investigaciones posteriores mostraron que correspondían a un
taxón no descrito hasta ahora.
Colección Ornitológica Phelps, Aptdo. 2009, Caracas 1010-A, Venezuela
MIGUEL LENTINO
1
AND ROBIN RESTALL
2
A NEW SPECIES OF AMAUROSPIZA BLUE SEEDEATER
FROM VENEZUELA
The Auk 120(3):600–606, 2003
1
E-mail: mlentino@reacciun.ve
2
Address correspondence to this author. E-mail:
restall@cantv.net
1
Lentino02E155.indd 06/30/2003, 12:14 PM1
mentary distribution is typical of nomadic bam-
boo-dependent seedeaters, for example, Slate-
colored Seedeater (Sporophila schistacea; Kratter
1997) and Sooty Grassquit (Tiaris fuliginosa; Sick
1993). It seems possible that all Amaurospiza are
nomadic to some extent.
There are no records for Amaurospiza in
Venezuela, nor has there been expectation
of any. The nearest species are removed by
both distance and the Andes in the case of A.
aequatorialis in southernmost Colombia and
Ecuador, and distance and the Amazon basin
in the case of A. moesta in southern Brazil and
eastern Paraguay (see Figs. 1 and 2). It was thus
a considerable surprise when Lentino collected
an adult male in Bolívar State, Venezuela. That
bird was deposited in the Phelps Ornithological
Collection, Caracas, where conrmed as an
Amaurospiza. On the next expedition to the same
area a few weeks later, another male and an adult
female were collected. Those specimens were
subsequently taken to the American Museum
of Natural History (AMNH), New York, where
compared with specimens of Amaurospiza from
the collections of the Louisiana State University
Museum of Natural Science, the National
Museum of Natural History, Washington, D.C.,
and the AMNH, and were conrmed as being
of an undescribed taxon. We propose naming
the new taxon
Amaurospiza carrizalensis sp. nov.
Carrizal Blue-black Seedeater
Semillero de Carrizales
Holotype.—Colección Ornitológica Phelps,
Caracas, Venezuela, COP no. 80449, male, Isla
Carrizal, Estado Bolívar, Venezuela, elevation
95 m, 07º54’N, 63°04’W, collected 25 July 2001
by M. Lentino and prepared by I. Carreño, origi-
nal eld number IC 569.
Diagnosis.—An emberizid, assignable to the
genus Amaurospiza by the combination of bill
shape, including general proportions plus the
unique ared basal tomia of the maxilla, (Fig. 2),
large size, and dark fuscous-gray coloring, well
washed with blue, and the white underwing,
separable from other members of the genus by
the density of coloration and black ammula-
tions on the breast, overall size, wing formula,
volume and shape of the bill, wing formula, and
general measurements (Table 1).
Description of holotype.—Capitalized color
names here and throughout this paper refer to
Ridgway’s color standards and nomenclature
(1912). Entire head, throat, and upper breast
black, well washed with Indigo Blue (Fig 3).
Mantle and wing-coverts Sooty, washed with
Indigo Blue, rump and uppertail-coverts Deep
Delft Blue with only the bases of the feathers
brownish-gray. Lesser wing-coverts are particu-
larly bright and with a slight iridescence. There
is a gentle gradation of dark to light color from
the crown to tail-coverts. Primaries, secondaries,
and tertials are dark Fuscous; primaries have
ne (0.4 mm) pale blue edges, almost whitish,
the secondaries are edged a little more broadly
(0.75 mm) with dull pale Indigo, the tertials are
somewhat abraded but appear to have been
edged with Indigo. The wing formula is 7=6,
8=5, 9=4 (see Fig. 4 for comparison with other
members of the genus and further comments
below). Rectrices are Fuscous Black, edged with
dull Indigo, more broad basally, broadest on the
innermost and central pairs of feathers. Throat
and breast are Indigo with black ammulations.
Flanks, belly, and undertail-coverts are dull
Sooty, washed lightly with Indigo. Underwing-
TABLE 1. Summary statistics (x ± SD, n) for measurements of species of Amaurospiza. All measurements are in
millimeters
Taxon
________________________________________________________________________________
Variable carrizali moesta aequatorialis concolor grandior relictus
Culmen exposed 13.35 ± 0.3, 3 10.2± 0.6, 27*** 9.8 ± 0.7, 3*** 9.7 ± 0.5, 11*** 10.5± 0.1, 3*** 10.6 ± 0.4, 4***
Bill height through
nares to base 9.1 ± 0.4, 3 8.4 ± 0.4, 27** 7.1 ± 1.6, 3* 7.8 ± 0.3, 11*** 8.3 ± 0.5, 3* 9 ± 0.4, 3
Bill width at base 10.2 ± 0.3, 3 9.7 ± 0.5, 27 8.4 ± 0.4, 3*** 8.4 ± 0.4, 11*** 8.3 ± 1.0, 2* 9.6 ± 0.3, 3*
Wing chord 63.7 ± 1.1, 3 61.7 ± 2.5, 27 58.8 ± 1.4, 3** 60.7 ± 1.7, 10** 60.8 ± 3.8, 3 65.7 ± 2.3, 3
Tarsus length 17 ± 0.5, 3 17.5 ± 0.8, 27 17.3 ± 0.6, 3 16.4 ± 0.8, 11 16.8 ± 0.9, 3 17 ± 0.7, 3
Tail length 50.2 ± 1.7, 3 51 ± 2.7, 27 46.7 ± 1.5, 3* 47.1 ± 4.6, 11 49.7 ± 3.5, 3 55.3 ± 3.2, 3*
Asterisks denote significance levels from two-sample t-tests comparing A. carrizalis with the taxa indicated. *P � 0.05; **P � 0.01; ***P � 0.001.
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coverts and axillars white. Plumage in good
condition, no molt in evidence, slight wear at
tips of tertials and rectrices.
Iris, Prout’s Brown. Bill black, tending to a
brownish translucency along edges of the to-
mium. Bill has an interesting shape, similar to
other species of Amaurospiza, but peculiarities
are more pronounced in this taxon. The max-
illa is shallow, almost like that of Slate-colored
Seedeater but not severely angled. Distal half of
the bill is like a pair of long-nosed or needle-
nose pliers (Bowman 1979) whereas basal tomia
of the maxilla forms a ange. Mandibular ra-
mus is noticeably concave, bending up and out
to meet the ange at the top of the rictus. Legs,
feet, toes, and nails black with soles grayish.
Measurements of holotype.—Total length
120 mm. Wing chord (not attened) 65.0 mm,
tail 51.0 mm, exposed culmen 11.93 mm, nare
to tip of bill 8.25 mm, height of bill measured
through nare 8.83 mm, width at base of bill
10.49 mm. Tarsus 16.6 mm. Weight 14.0 g.
Testes 8 × 5 mm.
Description of female.—Forehead to lower back,
FIG. 1. Approximate distributions of Amaurospiza (after Howell and Webb 1985, Ridgely and Tudor 1989, Hilty
and Brown 1989, and Ridgely and Greenfield 2001) with inset showing location of Isla Carrizal.
Lentino02E155.indd 06/30/2003, 12:14 PM3
wing-coverts, tertials, and rectrices Brussels
Brown, washed slightly with Dresden Brown
(Fig 5). The uppertail-coverts graduate into
Antique Brown. The wings and tail are Sepia
with Brussels Brown edges. Leading edges of
the primaries are slightly paler than those of
the secondaries. From chin to undertail-coverts
is Ochraceous-Buff washed at the sides of the
throat, the entire breast ank and undertail-co-
verts with a tone similar to both rich deep Clay
Color and Antique Brown. The underwing-co-
verts and axillars are pale Chamois or possibly
pale Cream Buff.
Iris, Prout’s Brown. Maxilla blackish, mandible
Olive-gray. Legs, feet, toes, and claws dark gray.
Measurements of female.—Total length 132 mm.
Wing chord 63.0 mm, tail 47.0 mm. Culmen
12.42 mm, nare to tip 8.42 mm, height of bill
8.26 mm, width 9.22 mm. Tarsus 17.66 mm.
Weight 14.0 g. Ovary 8 × 4 mm, diameter of fol-
licle 1 mm.
Specimens examined: Amaurospiza carrizalen-
sis.—Two specimens other than the holotype
were collected by Lentino and Carreño. Those
are COP 80451, female (described above), Isla
Carrizal, Río Caroni, Edo. Bolivar, 14 August
2001, and COP 80450, male, Isla Carrizal, Río
Caroni, Edo. Bolívar, 15 August 2001. Both
specimens were deposited at the COP (Table
2). The stomach contents of two specimens
included insects (possibly Curculionidae) and
unidentied vegetal mass.
Etymology.—The locality where the birds
were found is Carrizal Island in the Río Caroni
opposite the conuence with the Río Claro
(see Fig 1). Carrizo is a Spanish word for reed-
grass, but in the locality it is the word used for
bamboo. A carrizal is a forest of bamboo, thus
a translation of the location’s name would be
“Bamboo Island” or “Bamboo Forest Island.”
The birds were found among the extensive
spiny Guadua bamboo forest on the island, thus
it seems doubly appropriate to give the new
species this name, which works well in English
and Spanish, whereas the scientic name is an
adaptation of the word to Latin.
REMARKS
Variation within the type series.—In addition
to holotype, there are two other study skins
(Table 2). The paratype male has slightly stron-
ger black ammulations on the breast, other
FIG. 2. Comparisons between the bill profiles of
Amaurospiza. Upper, (A) moesta (Brazil), (B) car-
rizali (Venezuela), (C) relictus (Mexico); (D) aequato-
rialis (Ecuador), (E) grandior (Nicaragua), (F) concolor
(México to Panamá).
FIG. 3. Adult male Amaurospiza carrizali, taken on
Isla Carrizal showing bright blue of shoulder, and
character of bill. (Photo courtesy O. Linares.)
FIG. 4. Comparative wing–bill ratios for Amaurospiza.
Lentino02E155.indd 06/30/2003, 12:14 PM4
than that the two males are consistent. The fe-
male differs from the male in a way consistent
with the other species of Amaurospiza.
Variation within the species of Amaurospiza.—
The species of Amaurospiza have been separated
essentially on the basis of small plumage dif-
ferences and the shape and size of bill. The de-
scription of moesta, for example, was based on
the white axillars and a bill shape different to
that of concolor (Hartlaub 1853, Hellmayr 1938).
The differences are even smaller between gran-
dior and concolor, although we have shown the
data for grandior as separate from concolor.
The validity of relictus as a species has been
questioned (Hellmayr 1938, Paynter 1970); but
even so, relictus and concolor have been main-
tained as well-differentiated groups (Sibley
and Monroe 1990). There exist clear differences
in size and color between relictus and concolor
(Orr and Ray 1945), furthermore, Howell and
Webb (1995) have recently suggested that there
are song differences between the two forms.
Considering bill shape and morphological char-
acters mentioned above, we suspect that relictus
may well turn out to be a distinct species from
concolor.
Within the genus Amaurospiza, the bill of
Carrizal Blue-black Seedeater is the largest and
the one in which the typical characters are most
pronounced. (Table 1 and Fig. 2). The bill of car-
rizalensis is the largest in the genus and suggests
larger or tougher food items (Fig. 2). The wing:
bill ratio also separates it well from other mem-
bers of the genus (Fig. 4). The different wing
formula results in a more elongated, sharply
pointed wing, suggesting a greater capacity
for dispersion than other members of the genus
(Fig. 6).
All members in the genus have rounded
wings, and wing formulae within the genus
are similar. There appear to be two taxa that are
different from the rest, which are carrizalensis
with 7=6, 8=5, 9=4, and aequatorialis with (7,6,5),
8,9,4. The specimens of aequatorialis are few, and
we were unable to examine them all ourselves,
but were sent details from the museums where
the specimens reside, including the type at the
Natural History Museum, Tring. There is either
evidence of molt or some damage to the prima-
ries in those specimens, and it was only possible
to approximate the wing formula. Thus a larger
series could show that the formula of the outer-
most three primaries is either 7,6,5 or 7=6,5 or 6,
7=5. Each of those results in a distinct formula.
For that reason, combined with plumage and
morphological differences and a different dis-
tribution, we suspect that aequatorialis may well
turn out to be a distinct species from concolor,
with which it is currently included (Paynter
1970). We have shown the data for grandior as
separate from concolor since it is geographically
isolated from that of concolor in Nicaragua. The
distribution of concolor from Chiapas in México,
FIG. 5. Adult female A. carrizali, taken on Isla
Carrizal showing shape and character of tomia.
(Photo by M. Lentino.)
TABLE 2. Information from specimen labels of the holotype and paratypes of Amaurospiza carrizali
Museum no. Mass (g) Skull
a
Gonads
b
Fat Plumage
Males
COP 80449
c
14 100 8 � 5 – Light worn
COP 80450 12 100 10
� 6 – –
Female
COP 80451 14 100
8 � 4 – Light worn
a
Skull ossification (%).
b
Dimensions (mm) of left testis for males, ovary for females.
c
Holotype.
Lentino02E155.indd 06/30/2003, 12:14 PM5
to the Canal Zone in Panamá is so spotty, miss-
ing entire countries, as to merit more detailed
analysis than we have been able to make within
the scope of this description.
Habitat.—To date, the species has only been
found in stands of spiny Guadua latiolia and
Ripidoclaus sp. bamboo forest, within tropical
deciduous forests of the lower Río Caroni.
Distribution and status.—The species is pres-
ently known only from Carrizal Island in the
River Caroni. The area is currently undergoing
extensive forest clearance for dam development,
and Isla Carrizal has already been cleared.
There are extensive groves of Guadua bamboo
bordering the Caroni and the Guri Dam, some
of which will disappear in the actual dam ex-
pansion program. Further eld work is planned
to nearby localities that have bamboo forests in
the hope of establishing that the new species ex-
ists in other locations. Meanwhile we hope that
anybody visiting the area will be particularly
alert for this species, and promptly report any
sightings.
ACKNOWLEDGMENTS
We thank the curators and staff of the National
Museum of Natural History, Washington, D.C., and
the Louisiana State University (LSU) Museum of
Natural Science for sending specimens on loan, and
the American Museum of Natural History, New York
for receiving those specimens and for providing fa-
cilities for us to study there. S. Cardiff at LSU; J. Dean
at NMNH; P. Sweet and P. Cappianola at AMNH;
M. Adams at the Natural History Museum, Tring;
P. Ericson at the Department of Vertebrate Zoology,
Swedish Museum of Natural History, Stockholm; and
J. Trimble at the Museum of Comparative Zoology,
Harvard University, were all particularly helpful,
especially in providing data on wing formulae of the
specimens in their collections. The assistance of R.
Banks in getting the Latin naming of the new species
right was valuable. In addition, thanks to O. Linares,
coordinator of scientic research to the Caruachi Dam
Project and EDELCA, for supporting this investiga-
tion. Thanks to I. Carreño and A. Bermúdez for their
assistance in the eldwork. Thanks to J. V. Remsen, J.
P. O’Neill, and C. Rodner for critical readings of the
draft of this paper and their subsequent constructive
comments.
LITERATURE CITED
BOWMAN, R. I. 1979. Evolutionary patterns in
Darwin’s Finches. Occasional Papers of
California Academy of Sciences 44:107–140.
CHAPMAN, F. M. 1926. The Distribution of Bird Life
in Ecuador. Bulletin of the American Museum
of Natural History 55:614–615.
HELLMAYR, C. E. 1938. Catalogue of Birds of the
Americas and the Adjacent Islands, part 11.
Field Museum of Natural History Zoological
Series 13.
HILTY, S. L., AND W. L. BROWN. 1986. Guide to the
Birds of Colombia. Princeton University Press,
Princeton, New Jersey.
HOWELL, S. N. G., AND S. WEBB. 1995. A Guide to
the Birds of Mexico and N. Central America.
Oxford University Press, Oxford.
KRATTER, A. W. 1997. Bamboo Specialization by
Amazonian Birds. Biotropica 29: 100–110.
NAROSKY, T., AND D. YZURRIETA. 1987. Guía para
la identicación de las aves de Argentina y
Uruguay. Asociación Ornitológica del Plata,
Buenos Aires, Argentina.
ORR, R. T., AND M. S. RAY. 1945. Critical Comments
on Seedeaters of the Genus Amaurospiza.
Condor 47:225–228.
PAYNTER, R. A. P., JR., ED. 1970. Checklist of Birds
of the World, vol. 13. Museum of Comparative
Zoology, Cambridge, Massachusetts.
RIDGELY, R. S., AND P. J. GREENFIELD. 2001. The Birds
of Ecuador. Helm, London.
RIDGELY, R. S., AND J. GWYNNE. 1989. Birds of
Panamá. Princeton University Press, Princeton,
New Jersey.
RIDGELY, R. S., AND G. TUDOR. 1989. Birds of South
America, Oscine Passerines. University of
Texas Press, Austin.
RIDGWAY, R. 1912. Color Standards and Color
Nomenclature. Published by the author,
Washington, D.C.
ROWLEY, J. S. 1962. Nesting of Birds in Morelos.
Condor 64:265–266.
SALINAS, L., I. FRANKE, M. SAAME, AND J. FJELDSA.
1998. Primer registro de Amaurospiza concol-
or (Emberizidae, Passeriformes) para El Perú.
Libro de Resumes, VII Reunion Scientica,
FIG. 6. Comparative wing formulae of Amaurospiza.
(A) carrizalis 7=6,5=8,9=4, (B) grandior, concolor,relictus
and moesta 7=6=5,8=4,9, and (C) aequatorialis
7,6,5,9,8,4/(7=6=5)8,9,4/6,7=5,8,9,4 (see text for ex-
planation of variances).
Lentino02E155.indd 06/30/2003, 12:14 PM6
15–17 Abril, 1998. Inst. Investig. Cien. Biol.
Antonio Raimondi. Lima, Perú.
SICK, H. 1993. Birds in Brazil. Princeton University
Press, Princeton, New Jersey.
SLUD, P. 1964. Birds of Costa Rica. Bulletin of the
American Museum of Natural History. 128:
5–430.
STILES, F. G., AND A. SKUTCH. 1989. Birds of Costa
Rica. Princeton University Press, Princeton,
New Jersey.
WETMORE, A., R. F. PASQUIER, AND S. L. OLSON. 1984.
The Birds of the Republic of Panamá, pt. 4.
Smithsonian Institution Press, Washington
D.C.
Associate Editor: P. Stouffer
APPENDIX. Specimens examined during the course of
the preparation of this description.
Amaurospiza c. concolor
Canal Zone, Panamá
USNM 483119 m
AMNH 792653 m
AMNH 515474 m
AMNH 515 475 m
AMNH 801537 m
AMNH 801 536 m
AMNH 823289 m
AMNH 801539 f
AMNH 515476 f
Costa Rica
AMNH 392909 f
AMNH 515479 f
Amaurospiza c. grandior
Matagalpa, Nicaragua
AMNH 102650 m
AMNH 102649 m
AMNH 103812 f
Amaurospiza moesta
Porto Almeida, Brasil,
Missiones, Argentina
LSU 59707 m
LSU 59708 m
LSU 59709 m
LSU 59711 m
LSU 59722 m
LSU 59714 m
LSU 59719 m
LSU 59715 m
LSU 59703 f
LSU 59716 f
LSU 59718 f
LSU 59704 f
AMNH 774851 m
AMNH 774848 m
AMNH 774821 m
AMNH 774822 m
AMNH 774820 m
AMNH 774844 m
AMNH 774841
AMNH774846 m
AMNH 774816 m
AMNH 774850 m
AMNH 774824 f
AMNH 798524 f
AMNH 774840 f
AMNH 774815 f
Amaurospiza relictus
Morelos, Mexico
AMNH 778553 m
AMNH 778551 m
AMNH 778552 m
AMNH 778554 f
Amaurospiza aequatorialis
Ecuador
AMNH 173546 m
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