REVISION

OF "FALCO"NEOGENERAMENTAEVOLUTIONWETMORE

OF THEAND

THE

FALCONIDAE

JONATHAN J. BECKER
Divisionof Birds,NationalMuseumof NaturalHistory,Smithsonian
Institution,
Washington,
D.C. 20560USA

ABSTRACT.--"Falco"ramentaWetmore 1936 is redescribedand moved to a new genus as
Pedlofiierax ramenta (Wetmore). In addition to the holotypical distal end of the tarsometatarsus,this speciesis now known from a completetarsometatarsus,
humerus,and coracoidfrom mid-Miocene(Late Hemingfordianand Early Barstovian)fossillocalitiesin the Sheep
Creek and Olcott formations,northwesternNebraska.Pediolfferaxn. gen. is the primitive

sistergroupof the Falconinae.The earliestfossilrecordsnow known of the Falconinaeare
a speciesof ?Falcofrom the late Miocene of Idaho and Falcomediusfrom the late Miocene of
the Ukrainian S.S.R.Received5 June1986, accepted
4 November1986.

WETMORE(1936) described "Falco" ramenta

based on the distal end of a single right tarsometatarsusfrom a mid-Miocene locality in Nebraska.The holotype of this speciesapparently
was comparedonly with Falcocolumbarius
andF. sparverius,and differed from the former incaerulescens,
3; Falcosparverius,
2; F. columbarius,
26; F.
cherrug,2; F. biarmicus,1; F. subbuteo,
2; F. peregrinus,
1; F. berigora,1). Additionally, one skeleton each of
Buteojamaicensis,
Ictinia plumbea,Circuscyaneus,and
Neophronpercnopterus
were examined.
SYSTEMATICS

having the distal vascularforamen of the tarsometatarsus
more elevatedon the shaft in
Family FalconidaeVigors 1824
Pediofiieraxn. gen.
posterior view (Wetmore 1936). The incomplete, minimally diagnosticnature of the hoGenericdiagnosis.--As
with the Falconinae,thelotype has sincecausedthe systematicposition
head of the coracoidis rotated dorsally, causing
and validity of this speciesto be questioned the facies articularis clavicularis to be oriented(Jollie 1977).
! describe

mid-Miocene

here new material

fossillocalities

from correlativein

Nebraska

of"Falco" ramenta,revise the systematicpositionof this species,documentits stratigraphicrange,
and review all known Neogene recordsof thefamily Falconidae.
MATERIAL AND METHODS

Anatomical terminology follows Baumel et al.

more medially (especiallyin Falco).The foramen n. supracoracoideion the procoracoid isintermediate in position between that of the
Polyborinae and that of the Falconinae. The
humerusof Pediohierax

has a shallower

fossa

olecrani, a reduced process flexorius, and abrachial fossathat is oriented more nearly parallel to the shaft. It differs from all genera of
Falconidaein having the margo caudalismore(1979). Measurements were taken with Kanon dialrounded.

calipers,accurateto 0.05 mm and rounded to thenearest0.1 mm. Fossilspecimensexaminedare in the

nae in having a tarsometatarsuswith a shorthypotarsalridge ending distallyin a sharppointthat extendslessthan one-quarter of the length

Frick collections at the American

Museum of Natural

Pediohierax

differs

fromthe Falconi-

History (F:AM), the Idaho Museum of Natural His- of the tarsometatarsus.
tory (IMNH), and the National Museum of Natural
Etymology.--Frompedion,Greek, open counHistory,SmithsonianInstitution(USNM). Skeletonsof Falconidae examined (subfamily names are used

try or plains, and hierax,Greek, m., hawk.

Type species.--FalcoramentaWetmore (1936:
throughoutin an informalsenseto convenientlydes75).
ignate groupsof related genera):Herpetotherinae(Herpetotheres
cachinnans,5); Micrasturinae(Micrastur
Pediofiierax
ramen tasemitorquatus,
5; M. ruficollis,2); Polyborinae(Daptrius(Wetmore 1936) n. comb.
ater,5; D. americanus,
3; Milvagochimachima,
7; M. chimango,6; Phalcoboenus
australis,6; Polyborusplancus
cheriway,6; Spiziapteryxcircumcinctus,3); Falconinae

Holotype.--Distal end of right tarsometatar(Polihierax
semitorquatus,
7; P. insignis,1; Microhierax sus,USNM 13898.VertebratePaleontologycol270

The Auk 104: 270-276. April 1987

April 1987]

NeogeneFalconidae

lections,National Museum of Natural History,
Smithsonian

Institution.

Newly referredmaterial.--F:AM 8633, nearlycomplete right humerus, missing part of thedeltoid crest and internal tuberosity, from
BoulderQuarry; F:AM 10151,completeleft tarsometatarsus,from Echo Quarry; F:AM 10214,

completeleft coracold,from ThomsonQuarry;
F:AM 10068, humeral end left coracold, from

ObservationQuarry. Thesespecimensare fromthe Frick collections,Department of Vertebrate
Paleontology, American Museum of Natural
History.
Locality/horizon.--The holotype (USNM

13898) originated in "MerychippusQuarry,"southwest corner of NW •A, Sec. 14, T. 31, R. 47

Dawes Co., Nebraska. Wetmore (1936), citing

271

lian fossilsfrom it agree with those from otherquarries in this formation.
A black vitric tuff (Sheep Creek Ash No. 3 ofSkinner et al. 1977; KA 891 of Evernden et al.

1964) occurs approximately 28 stratigraphic
meters above the Thomson Quarry and has
yielded a zircon fissiontrack date of 17.5 + 0.5
and 16.5 + 0.6 MYBP (million years before
present) (Tedford et al. in press).These fission
track dates approximate the geologic age of
Pediohierax

ramenta.

Diagnosis.--Asfor the genus.
Description.--Theskeletal elements of Pediohieraxramentaare smaller than in any memberof the Polyborinae and are comparablein size
to small males of Falcosparveriusand F. columbarius.Becauseof the great size variation be-

tween the sexesin this family, and becauseeachsha, reported that this quarry was probably specimenis from a separatelocality representequivalent to the Sheep Creek Beds,a sugges- ing a slightlydifferentinterval of geologictime,tion followed without comment by Brodkorb little can be said concerningthe limb proporcorrespondence from the collector Ted Galu-(1964). Galusha (1975) later established that thislocality is near Elias's(1942) type section for
the "SandCanyonMember of the SheepCreek
Formation"and is correlative

to Observation

Quarry, Sand Canyon Beds.
Excluding the material from Observation
Quarry, each referred specimenis from a separate quarry locality in the Sheep Creek or O1cott formations, Sioux Co., Nebraska. The O1-

cott Formation [= Lower Snake Creek Beds ofMatthew (1924)] directly overlies (unconformably) the Sheep Creek Formation. Skinner etal. (1977) discussedthe following quarries indetail and placed them in the following stratigraphic sequence.Thomson Quarry, Late Hemingfordian, is from the baseof the middle partof Sheep Creek Formation. Observation Quarry, early Early Barstovian,is from the Sand
Canyon Beds, Dawes Co., Nebraska. Observation Quarry is located48-64 km from the othertions of Pediohierax.

Measurements.--Coracoid (F:AM 10214, F:AM

10068):length from head through internal distal angle (25.4, --); length from head throughscapularfacet(7.7, 8.0);leastdepth of head (2.5,2.4); width of midshaft (3.3, --); depth of midshaft (2.4, --); length from internal distal angle
to procoracoid process(19.2, --). Humerus (F:AM 8633):greatestlength from the head of thehumerus through the midpoint of the lateral(ventral) condyle (35.3); transversewidth of
midshaft (3.3); depth of midshaft (2.8); depthof head, measuredparallel to the axis of thehead (7.5); transverse width of distal end fromthe ventralto the dorsalepicondyle(7.1);depthof distal end from cranial face of external (dor-lated lithically to the Olcott Formation (Skin-sal)condylethroughridge slightlymediadfrom
externaltricipital groove,measuredat right angles to the long axis of the shaft (4.0); depth
from the tuberculum supracondylareventrale
through the processusflexoris, measured atright angles to the long axis of the shaft (3.2).

ner et al. 1977), but the undescribed vertebrate

Tarsometatarsus (F:AM 10151, USNM

localities

included

here

and

cannotbe corre-fauna from this quarry may be intermediatebetween the faunas of the Sheep Creek Forma-

13898):

length from intercondylar eminence throughtrochleafor digit III (37.0, --); transversewidthtion and the Olcott Formation (Tedford et al.
of midshaft (2.5, 2.3); depth of midshaft (2.2,
in press).BoulderQuarry, Early Barstovian,is 2.0); intercondylar eminence to middle of tufrom the type section of the Olcott Formation, berclefor m. tibialis cranialis(6.3, --); greatest
representing the lower stratigraphic levels of transverse width proximal articular surface,
this formation. Echo Quarry, Early Barstovian, measuredacrossdorsal surface(5.7, --); greatis from an undetermined stratigraphicposition estdepth medial cotyla(3.2, --); greatestdepth
within the Olcott Formation, but the mammalateral cotyla (3.6, --); depth of proximal end,

272

JONATHAN
J. BtiClCF,
R[Auk,Vol. 104

C
A

[3

d

April 1987]

NeogeneFalconidae

273

measuredfrom dorsal edge of the proximal articular surfacethrough the hypotarsalcrest(5.7,--); greatesttransversewidth of distalend (*5.8,'5.1) (* = specimenbroken, actual measurement would be greater).
Genus Falco Linnaeus

•G•ø

1758

?Falcosp.

Material.--Nearly complete left coracold,
IMNH 27937, Vertebrate Paleontology collections, Idaho Museum of Natural History. Collected 22 June 1968by JohnA. White.
Locality.--IMNH VertebratePaleontologylocality 67001, Owyhee Co., Idaho (NW •A,Sec.
19, T. 16S,R. 5W, Star Valley Quadrangle,U.S.
GeologicalSurvey 7.5-min seriestopographicalmap, 1973). Early Hemphillian Land Mammal
Age (late Miocene), approximately 8 MYBP
(Becker1980). Sedimentsare probably correlative to the Big Island Formation (Coats 1985).
Description.--Coracoid
is referable to the Falconinae in having the foramen n. supracoracoidei placed along medial margin of procora-Fig. 2. Proposedphylogenyof the majorgroupsof the Falconidae
basedon osteologicalcharactersandusing the Accipitridaeas an outgroup.Sharedderived characters for each node are defined in the text.

DISCUSSION

cold. Similar in size to Falco columbarius(F.

A phylogeny,basedon sharedderived osteologicalcharacters(Fig. 2), is essentiallythe sameasthoseproposedby Ridgway(1875, 1876)andJollie(1977)exceptthat Spiziapteryx
is not alliedwith the falconets, following Olson (1976a).
Charactersthat define the family Falconidae(Fig. 2, node 1) are given by Ridgway (1875,

sparverius,
F. tinnunculus,
and F. rufigulariusare
smaller; all other New World speciesare larger), but distinguishedfrom thesespeciesby thegreater length of glenold facet, smaller lengthof coracold,and presenceof a strong crest on

actersinclude the presenceof a long supraciliary processof the lacrimal,presumablyfrom asingle ossificationcenter,and the procoracoid
processof the coracoldbeing produced for-the ventral, sternal end of the coracold.
Measurements.--Data
are IMNH
27937;

1876) and Jollie (1976, 1977). Osteologicalchar-ward

to contact

the furculum.

Micrastur and Herpetotheres each have amean _+SD, observedrange of Falcocolumbarius unique, highly derived tarsometatarsus(Jollie(n = 26:4 males, 11 females, 11 unknown sex). 1977).In addition, thesegenera sharewith theAsterisksindicate specimenbroken, measure- Accipitridae the primitive conditions of un-ment estimated.Length from the processusac- fused dorsal vertebrae (Storer 1982) and lack arocoracoideusthrough the midpoint of the lateral opening of the extensorcanal on thesternal end (*26.6; 28.57 _+ 1.58, 26.1-31.3).
distal end of the tibiotarsus(a very small openLength from the midpoint of the sternal facet ing may be presentin someindividuals of Mito the triosseal canal (21.4; 21.86 _+ 2.20, 19.9crastur).These conditions suggestthat Micras27.6). Length from the external end of the ster- tur and Herpetotheres
have long been separate
nal facet through the internal distal angie from the other members of the Falconidae and('10.6; 10.50 + 0.66, 9.6-11.9). Length of the probablyfrom eachother.
glenold facet from the most cranial portion of
The Falconinaeand the Polyborinae(Fig. 2,
the glenold through the most caudal point of node 2) are united by the presenceof the dethe scapularfacet(6.6; 5.89 _+0.42, 5.1-7.0).
rived notarium and the lateral opening of theFig. 1. Bonesof Pediohierax
ramenta.(A, B) Referred right humerus,F:AM 8633:(A) caudal(ancohal)view,(B) cranial (palmer) view. (C, D) Referred left coracoid,F:AM 10214:(C) dorsalview, (D) ventral view. (E-H)
Referredleft tarsometatarsus,
F:AM 10151:(E) anterior (dorsal)view, (F) posterior(plantar) view, (G) proximal
end view, (H) distal end view. (I-K) Holotype, USNM 13898,distal end of right tarsometatarsus:(I) anterior(dorsal)view, (J) posterior(plantar) view, (K) distal end view. All photographsare 2 x natural size.

274
extensor

JON^T•^NJ. BECKER
canal of the tibiotarsus.

[Auk,Vol. 104

Both have amediatebetween the primitive conditionof the
Polyborinae (foramen n. supracoracoideiset
well within the procoracoidprocessaway fromthe medial margin) and the derived conditiona very long ridge extending down from the of the Falconinae (incisura n. supracoracoidei
hypotarsusto blend gradually with the shaft. located in the medial margin of the procoraThe Polyborinae have a shortened hypotarsal coid processas either an open notch or closed
ridge that ends distally in a sharp point, and by a tendinousthread that may or may not bethat usually extendsless than one-quarterof ossified;Olson 1976a).
The coracoid of both Pediohierax and Falco has
the length of the tarsometatarsus.
The polyborine tarsometatarsusis probably the closestto the facies articularis clavicularis excavated in
the primitive condition for this family (Jollie medial view. This apparently derived character
1976, 1977). Therefore, the charactersof the tar- may indicatethat Falcoand Pediohierax
are moresometatarsus shared between Pediohierax and thecloselyrelatedto eachother than are Falcoand
Polyborinaeare primitive and cannot be used the falconets, in which case the falconine tarsometatarsuswould have developed indepento support a closesystematicrelationship.
Spiziapteryx
was associatedtraditionally with dently in the falconetsand in Falco.
the falconets Polihierax and Microhierax (SuschCharactersof the humerusprovide little syskin 1905, Peters 1931, Brown and Amadon
tematic evidence, becauseof the difficulty in1968). Olson (1976a) found charactersthat dis- determining their polarities. The humerus ofis similar to that of both the Polybotinguish Spiziapteryxfrom the falconets and Pediohierax
suggestedthat Spiziapteryxshould be placed rinae and the Falconinae (excluding Spiziaptecloserto the caracaras.Spiziapteryx
has a prim- ryx, which has a slender,stronglycurvedhuitive polyborine tarsometatarsusand shares merus). The similar orientation of the brachial
tarsometatarsusthat is square in crosssection,
but the tarsometatarsus
differs markedly in hypotarsalstructure.The falconinehypotarsushas

with the caracaras the reduction

in interorbital

ossification(Olson 1976a), possiblydevelopedin parallel. It alsohasa number of unique (autapomorphic) characteristics that include astronglycurvedhumerusand a relatively elongatedcoracoid.Spiziapteryx
shareswith the Falconinae(Fig. 2, node 3) the presenceof a prominent "tooth" on the maxillary tomium.
Although someindicationsof this tooth can beseen on the tomium of somegenera of caracaras (Milvagoand Phalcoboenus),
it cannotbe detectedon the underlying bone (Ridgway 1876).
Caracarasare a distinctive neotropical groupof falconids (Ridgway 1876, Brown and Amadon 1968, Vuilleumier 1970, Olson 1976b, Jollie

1977). All caracarashave the interorbital sep-

tum poorly ossified,possiblydevelopedin parallel with Spiziapteryx,
an elongated shape ofthe skull, and a reducedsupraciliaryprocessof

fossa between

theFalconinae

andPediohierax

may provide additional supportfor a closesystematicrelationship,but other charactersof thehumerus (a shallow fossaolecrania and a less-developed process flexorius) are probablyprimitive as the conditionsseen in Pediohierax
are similar

to those of the caracaras.

The reductionof palatinesto noncancellous
cupsor shelvesand the placementof the coracoid fenestra on the internal margin of theprocoracoidprocess(Olson 1976a) unite thefalconetswith Falco(Fig. 2, node 5). These twogroupsalso sharea falconine tarsometatarsus.
The Falconidae have a long, disjunct fossil
history.The earliestreportedoccurrenceis preNeogenein the Eo-OligocenePhosphoritesdu

Quercy, France (Mourer-Chauvir•

1982).

Umanskaja(1981) describedFalcomediusbasedon a left carpometacarpusfrom alluvial sands
the lacrimal bone (Olson 1976a).The exact sys- of Maeotian age (late Miocene) from Cheretematicrelationshipof Spiziapteryx
to the cara- vichnyi in the Odessadistrict, Ukrainian S.S.R.
carasis still uncertain.Spiziapteryx
may be the This smallspeciesis closelyrelatedto Falcotinsistergroup to the caracaras,or it may be the nunculus,F. vespertinus,
and F. naumanni(Umansistergroup to the Falconinae + Pediohierax
as skaja1981:19). The geologicageof this species
indicated in Fig. 2.
is comparableto that of ?Falcofrom Idaho, disPediohieraxis allied with the Falconinae by cussedabove.The only other proposedfalconthe charactersof the coracoid (Fig. 2, node 4). id from the Neogene of Europeis Falcopisianus
The humeral end of the coracoid is rotated dorPortis (1887), which was moved to the Colsally. The foramen n. supracoracoideiis inter- umbidae (Olson 1985).

April 1987]

NeogeneFalconidae

275

ACKNOWLEDGMENTS
One Neogene fossil speciesis known from
Asia. Kurochkin (1985) recently revised SushI thank S. L. Olson and R. L. Zusi for their comkiniapliocaena
Tugarinov (1935) from the early mentson the manuscript.For the loan of fossiland
Pliocene"Gusinyi petelet" locality of Pavlodar modern specimens,I thank P. Brodkorb, V. M. Dia(lower levels) on the banks of the Irtysh River dosz (NSF grant BMS 7200102),C. Houlton, S. L. Olin eastern Kazakh S.S.R.The descriptions and son, R. W. Schreiber, R. H. Tedford, C. Trost, J. A.
photographsof the coracoldand tarsometatar- White, and R. L. Zusi. I am grateful to R. H. Tedford
susof Sushkinia
given by Kurochkin(1985)show for his commentson the stratigraphy of the Frickclearlythat Sushkinia
is closelyrelatedto, if not fossil localities,to A. Elzanowskifor translatingcritical portions of articles from Russian,and to S. L.
actuallycongenericwith, the genusFalco.

Theearliest

recordof falconids

from

South

Olson for calling my attention to some of the additional material of Pediohierax.
This work was supported by the Frank M. Chapman Memorial Fund,
Sigma Xi, and a Smithsonian PostdoctoralFellowship. Photographsare by Victor E. Krantz.

America is Badiostes
patagonicus,
originally describedby Ameghino (1894) asan owl from theSanta Cruz Formation (Santacrucian, early
Miocene)of Patagonia,Argentina. Basedon the
published illustrations of this species, Wetmore (1922) moved this speciesto tho FalconLITERATURE CITED
idae, a decisionsupportedby Lambrecht(1933),
Brodkorb(1964), and Olson (1985). Olson (1985) AMEGHINO, F. 1894. Sur les oiseaux fossiles de Patarefined the systematicplacementof this species
gonie. Pp. 501-602 in Boletin del Instituto GeobecauseAmeghino'sillustrationsof hypotarsal
gr•phico Argentino, tomo XV, cuadernosXI y
structurewere

sufficient

to include

it in theXII. [Published 1895.]

Polyborinaeon the structureof the hypotarsus. BAUMEL,J. J., A. S. KING, A.M. LUCAS,J. E. BREAZILE,& H. E. EVANS. 1979. Nomina anatomica avium.
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Pocatello, Idaho State Univ.
thus removing the possibility that these two
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P. 1964. Catalogueof fossilbirds. Part 2
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ever, the genericrelationshipsof Badiostes
require further evaluationwhen the holotype of
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Falconidae

from

an

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Neuqu•n province,Argentina, of Friasianage(late Miocene).

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