REVISION OF "FALCO" RAMENTA WETMORE AND THE NEOGENE EVOLUTION OF THE

JONATHAN J. BECKER Divisionof ,National Museum of NaturalHistory, Smithsonian Institution, Washington,D.C. 20560 USA

ABSTRACT.--"Falco"ramenta Wetmore 1936 is redescribed and moved to a new genus as Pedlofiierax ramenta (Wetmore). In addition to the holotypical distal end of the tarsometa- tarsus,this speciesis now known from a complete tarsometatarsus,humerus, and coracoid from mid-(Late Hemingfordian and Early Barstovian)fossil localities in the Sheep Creek and Olcott formations,northwestern Nebraska. Pediolfferax n. gen. is the primitive sistergroup of the Falconinae.The earliestfossil records now known of the Falconinaeare a speciesof ?Falcofrom the late Miocene of Idaho and Falcomedius from the late Miocene of the Ukrainian S.S.R. Received5 June1986, accepted4 November1986.

WETMORE(1936) described "Falco" ramenta caerulescens,3; Falco sparverius, 2; F. columbarius,26; F. based on the distal end of a single right tarso- cherrug,2; F. biarmicus,1; F. subbuteo,2; F. peregrinus, metatarsusfrom a mid-Miocene locality in Ne- 1; F. berigora,1). Additionally, one skeleton each of braska.The holotype of this speciesapparently Buteojamaicensis, Ictinia plumbea,Circus cyaneus, and Neophronpercnopterus were examined. was comparedonly with Falcocolumbarius and F. sparverius,and differed from the former in SYSTEMATICS having the distal vascularforamen of the tar- sometatarsus more elevated on the shaft in Family FalconidaeVigors 1824 posterior view (Wetmore 1936). The incom- Pediofiierax n. gen. plete, minimally diagnostic nature of the ho- Genericdiagnosis.--As with the Falconinae,the lotype has sincecaused the 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 here new material from correlative more medially (especiallyin Falco).The fora- mid-Miocene fossil localities in Nebraska of men n. supracoracoideion the procoracoid is intermediate in position between that of the "Falco" ramenta,revise the systematicposition Polyborinae and that of the Falconinae. The of this species,document its stratigraphicrange, humerus of Pediohierax has a shallower fossa and review all known Neogene recordsof the olecrani, a reduced process flexorius, and a family Falconidae. brachial fossathat is oriented more nearly par- MATERIAL AND METHODS allel to the shaft. It differs from all genera of Anatomical terminology follows Baumel et al. Falconidaein having the margo caudalismore (1979). Measurements were taken with Kanon dial rounded. Pediohierax differs from the Falconi- calipers,accurate to 0.05 mm and rounded to the nae in having a tarsometatarsuswith a short nearest0.1 mm. Fossilspecimens examined are in the hypotarsalridge ending distally in a sharppoint Frick collections at the American Museum of Natural that extends lessthan one-quarter of the length History (F:AM), the Idaho Museum of Natural His- of the tarsometatarsus. tory (IMNH), and the National Museum of Natural Etymology.--Frompedion, Greek, open coun- History,Smithsonian Institution (USNM). Skeletons try or plains, and hierax,Greek, m., hawk. of Falconidae examined (subfamily names are used throughoutin an informalsense to convenientlydes- Type species.--Falcoramenta Wetmore (1936: ignate groups of related genera): 75). (Herpetotherescachinnans, 5); Micrasturinae(Micrastur semitorquatus,5; M. ruficollis,2); Polyborinae(Daptrius Pediofiierax ramen ta ater, 5; D. americanus,3; Milvagochimachima, 7; M. chi- (Wetmore 1936) n. comb. mango,6; Phalcoboenusaustralis, 6; Polyborusplancus cheriway,6; Spiziapteryxcircumcinctus, 3); Falconinae Holotype.--Distal end of right tarsometatar- (Polihieraxsemitorquatus, 7; P. insignis,1; sus,USNM 13898.Vertebrate Paleontologycol-

270 The Auk 104: 270-276. April 1987 April 1987] NeogeneFalconidae 271 lections,National Museum of Natural History, lian fossilsfrom it agree with those from other Smithsonian Institution. quarries in this formation. Newly referredmaterial.--F:AM 8633, nearly A black vitric tuff (Sheep Creek Ash No. 3 of complete right humerus, missing part of the Skinner et al. 1977; KA 891 of Evernden et al. deltoid crest and internal tuberosity, from 1964) occurs approximately 28 stratigraphic Boulder Quarry; F:AM 10151,complete left tar- meters above the Thomson Quarry and has sometatarsus,from Echo Quarry; F:AM 10214, yielded a zircon fissiontrack date of 17.5 + 0.5 completeleft coracold,from ThomsonQuarry; and 16.5 + 0.6 MYBP (million years before F:AM 10068, humeral end left coracold, from present) (Tedford et al. in press).These fission ObservationQuarry. Thesespecimens are from track dates approximate the geologic age of the Frick collections,Department of Vertebrate Pediohierax ramenta. Paleontology, American Museum of Natural Diagnosis.--Asfor the genus. History. Description.--Theskeletal elements of Pedio- Locality/horizon.--The holotype (USNM hieraxramenta are smaller than in any member 13898) originated in "MerychippusQuarry," of the Polyborinae and are comparablein size southwest corner of NW •A, Sec. 14, T. 31, R. 47 to small males of Falcosparverius and F. colum- Dawes Co., Nebraska. Wetmore (1936), citing barius.Because of the great size variation be- correspondence from the collector Ted Galu- tween the sexesin this family, and becauseeach sha, reported that this quarry was probably specimenis from a separatelocality represent- equivalent to the Sheep Creek Beds,a sugges- ing a slightlydifferent interval of geologictime, tion followed without comment by Brodkorb little can be said concerning the limb propor- (1964). Galusha (1975) later established that this tions of Pediohierax. locality is near Elias's (1942) type section for Measurements.--Coracoid (F:AM 10214, F:AM the "Sand CanyonMember of the SheepCreek 10068):length from head through internal dis- Formation" and is correlative to Observation tal angle (25.4, --); length from head through Quarry, Sand Canyon Beds. scapularfacet (7.7, 8.0); leastdepth of head (2.5, Excluding the material from Observation 2.4); width of midshaft (3.3, --); depth of mid- Quarry, each referred specimenis from a sep- shaft (2.4, --); length from internal distal angle arate quarry locality in the Sheep Creek or O1- to procoracoid process(19.2, --). Humerus (F: cott formations, Sioux Co., Nebraska. The O1- AM 8633):greatest length from the head of the cott Formation [= Lower Snake Creek Beds of humerus through the midpoint of the lateral Matthew (1924)] directly overlies (unconform- (ventral) condyle (35.3); transversewidth of ably) the Sheep Creek Formation. Skinner et midshaft (3.3); depth of midshaft (2.8); depth al. (1977) discussedthe following quarries in of head, measured parallel to the axis of the detail and placed them in the following strati- head (7.5); transverse width of distal end from graphic sequence.Thomson Quarry, Late Hem- the ventral to the dorsalepicondyle (7.1); depth ingfordian, is from the baseof the middle part of distal end from cranial face of external (dor- of Sheep Creek Formation. Observation Quar- sal)condyle through ridge slightlymediad from ry, early Early Barstovian, is from the Sand externaltricipital groove,measured at right an- Canyon Beds, Dawes Co., Nebraska. Observa- gles to the long axis of the shaft (4.0); depth tion Quarry is located48-64 km from the other from the tuberculum supracondylareventrale localities included here and cannot be corre- through the processusflexoris, measured at lated lithically to the Olcott Formation (Skin- right angles to the long axis of the shaft (3.2). ner et al. 1977), but the undescribed vertebrate Tarsometatarsus (F:AM 10151, USNM 13898): fauna from this quarry may be intermediate be- length from intercondylar eminence through tween the faunas of the Sheep Creek Forma- trochleafor digit III (37.0, --); transversewidth tion and the Olcott Formation (Tedford et al. of midshaft (2.5, 2.3); depth of midshaft (2.2, in press).Boulder Quarry, Early Barstovian,is 2.0); intercondylar eminence to middle of tu- from the type section of the Olcott Formation, bercle for m. tibialis cranialis(6.3, --); greatest representing the lower stratigraphic levels of transverse width proximal articular surface, this formation. Echo Quarry, Early Barstovian, measuredacross dorsal surface(5.7, --); great- is from an undetermined stratigraphic position est depth medial cotyla (3.2, --); greatestdepth within the Olcott Formation, but the mamma- lateral cotyla (3.6, --); depth of proximal end, 272 JONATHANJ. BtiClCF, R [Auk, Vol. 104

C A [3

d April 1987] NeogeneFalconidae 273 measuredfrom dorsal edge of the proximal ar- ticular surfacethrough the hypotarsalcrest (5.7, --); greatesttransverse width of distalend (*5.8, •G•ø '5.1) (* = specimenbroken, actual measure- ment would be greater).

Genus Falco Linnaeus 1758 ?Falcosp.

Material.--Nearly complete left coracold, IMNH 27937, Vertebrate Paleontology collec- Fig. 2. Proposedphylogeny of the majorgroups tions, Idaho Museum of Natural History. Col- of the Falconidaebased on osteologicalcharacters and lected 22 June 1968 by JohnA. White. using the Accipitridaeas an outgroup.Shared de- Locality.--IMNH VertebratePaleontology lo- rived characters for each node are defined in the text. cality 67001, Owyhee Co., Idaho (NW •A,Sec. 19, T. 16S,R. 5W, Star Valley Quadrangle,U.S. GeologicalSurvey 7.5-min seriestopographical DISCUSSION map, 1973). Early Hemphillian Land Mammal Age (late Miocene), approximately 8 MYBP A phylogeny,based on sharedderived osteo- (Becker 1980). Sedimentsare probably correla- logicalcharacters (Fig. 2), is essentiallythe same tive to the Big Island Formation (Coats 1985). as thoseproposed by Ridgway (1875, 1876)and Description.--Coracoidis referable to the Fal- Jollie(1977) except that Spiziapteryxis not allied coninae in having the foramen n. supracora- with the falconets, following Olson (1976a). coidei placed along medial margin of procora- Charactersthat define the family Falconidae cold. Similar in size to Falco columbarius(F. (Fig. 2, node 1) are given by Ridgway (1875, sparverius,F. tinnunculus,and F. rufigulariusare 1876) and Jollie (1976, 1977). Osteologicalchar- smaller; all other New World speciesare larg- actersinclude the presenceof a long supracili- er), but distinguishedfrom thesespecies by the ary processof the lacrimal,presumably from a greater length of glenold facet, smaller length single ossificationcenter, and the procoracoid of coracold,and presenceof a strong crest on processof the coracoldbeing produced for- the ventral, sternal end of the coracold. ward to contact the furculum. Measurements.--Data are IMNH 27937; Micrastur and Herpetotheres each have a mean _+SD, observedrange of Falcocolumbarius unique, highly derived tarsometatarsus(Jollie (n = 26:4 males, 11 females, 11 unknown sex). 1977). In addition, these genera share with the Asterisksindicate specimenbroken, measure- Accipitridae the primitive conditions of un- ment estimated.Length from the processusac- fused dorsal vertebrae (Storer 1982) and lack a rocoracoideusthrough the midpoint of the lateral opening of the extensorcanal on the sternal end (*26.6; 28.57 _+ 1.58, 26.1-31.3). distal end of the tibiotarsus(a very small open- Length from the midpoint of the sternal facet ing may be presentin someindividuals of Mi- to the triosseal canal (21.4; 21.86 _+ 2.20, 19.9- crastur).These conditions suggestthat Micras- 27.6). Length from the external end of the ster- tur and Herpetothereshave 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 each other. 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 de- the scapularfacet (6.6; 5.89 _+0.42, 5.1-7.0). rived notarium and the lateral opening of the

Fig. 1. Bonesof Pediohieraxramenta. (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) Referred left 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 JON^T•^NJ. BECKER [Auk, Vol. 104 extensor canal of the tibiotarsus. Both have a mediatebetween the primitive condition of the tarsometatarsusthat is square in crosssection, Polyborinae (foramen n. supracoracoideiset but the tarsometatarsusdiffers markedly in hy- well within the procoracoidprocess away from potarsalstructure. The falconinehypotarsus has the medial margin) and the derived condition a 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 procora- The 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 be that usually extends less than one-quarterof ossified; Olson 1976a). the length of the tarsometatarsus.The polybor- The coracoid of both Pediohierax and Falco has ine 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 Pediohieraxare more sometatarsus shared between Pediohierax and the closelyrelated to eachother than are Falcoand Polyborinae are primitive and cannot be used the falconets, in which case the falconine tar- to support a closesystematic relationship. sometatarsuswould have developed indepen- Spiziapteryxwas associatedtraditionally with dently in the falconetsand in Falco. the falconets and Microhierax (Susch- Charactersof the humerus provide little sys- kin 1905, Peters 1931, Brown and Amadon tematic evidence, becauseof the difficulty in 1968). Olson (1976a) found charactersthat dis- determining their polarities. The humerus of tinguish Spiziapteryxfrom the falconets and Pediohieraxis similar to that of both the Polybo- suggestedthat Spiziapteryxshould be placed rinae and the Falconinae (excluding Spiziapte- closerto the caracaras.Spiziapteryx has a prim- ryx, which has a slender,strongly curved hu- itive polyborine tarsometatarsusand shares merus). The similar orientation of the brachial with the caracaras the reduction in interorbital fossa between the Falconinae and Pediohierax ossification(Olson 1976a), possibly developed may provide additional supportfor a closesys- in parallel. It alsohas a number of unique (aut- tematicrelationship, but other charactersof the apomorphic) characteristics that include a humerus (a shallow fossa olecrania and a less- stronglycurved humerus and a relatively elon- developed process flexorius) are probably gatedcoracoid. Spiziapteryx shares with the Fal- primitive as the conditions seen in Pediohierax coninae(Fig. 2, node 3) the presenceof a prom- are similar to those of the caracaras. inent "tooth" on the maxillary tomium. The reductionof palatinesto noncancellous Although someindications of this tooth can be cupsor shelvesand the placementof the cor- seen on the tomium of some genera of caraca- acoid fenestra on the internal margin of the ras (Milvagoand Phalcoboenus),it cannot be de- procoracoidprocess (Olson 1976a) unite the tectedon the underlying bone (Ridgway 1876). falconetswith Falco(Fig. 2, node 5). These two Caracarasare a distinctive neotropical group groupsalso share a falconine tarsometatarsus. of falconids (Ridgway 1876, Brown and Ama- The Falconidae have a long, disjunct fossil don 1968, Vuilleumier 1970, Olson 1976b, Jollie history.The earliestreported occurrence is pre- 1977). All caracarashave the interorbital sep- Neogenein the Eo-OligocenePhosphorites du tum poorly ossified,possibly developed in par- Quercy, France (Mourer-Chauvir• 1982). allel with Spiziapteryx,an elongated shape of Umanskaja(1981) describedFalco medius based the skull, and a reducedsupraciliary process of on a left carpometacarpusfrom alluvial sands the lacrimal bone (Olson 1976a).The exact sys- of Maeotian age (late Miocene) from Chere- tematicrelationship of Spiziapteryxto the cara- vichnyi in the Odessadistrict, Ukrainian S.S.R. carasis still uncertain.Spiziapteryx may be the This small speciesis closelyrelated to Falcotin- sistergroup to the caracaras,or it may be the nunculus,F. vespertinus,and F. naumanni(Uman- sister group to the Falconinae + Pediohieraxas skaja1981: 19). The geologicage of this species indicated in Fig. 2. is comparableto that of ?Falcofrom Idaho, dis- Pediohieraxis allied with the Falconinae by cussedabove. The only other proposedfalcon- the charactersof the coracoid (Fig. 2, node 4). id from the Neogene of Europe is Falcopisianus The humeral end of the coracoid is rotated dor- Portis (1887), which was moved to the Col- sally. The foramen n. supracoracoideiis inter- umbidae (Olson 1985). April 1987] NeogeneFalconidae 275

One Neogene fossil speciesis known from ACKNOWLEDGMENTS

Asia. Kurochkin (1985) recently revised Sush- I thank S. L. Olson and R. L. Zusi for their com- kiniapliocaena 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. Ol- in 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 Sushkiniagiven by Kurochkin (1985)show for his commentson the stratigraphy of the Frick clearly that Sushkiniais closelyrelated to, if not fossil localities,to A. Elzanowskifor translating crit- actuallycongeneric with, the genusFalco. ical portions of articles from Russian,and to S. L. The earliest record of falconids from South Olson for calling my attention to some of the addi- tional material of Pediohierax.This work was sup- America is Badiostespatagonicus, originally de- ported by the Frank M. Chapman Memorial Fund, scribedby Ameghino (1894) asan owl from the Sigma Xi, and a Smithsonian PostdoctoralFellow- Santa Cruz Formation (Santacrucian, early ship. Photographsare by Victor E. Krantz. Miocene) of Patagonia,Argentina. Basedon the published illustrations of this species, Wet- more (1922) moved this speciesto tho - idae, a decisionsupported by Lambrecht(1933), LITERATURE CITED Brodkorb(1964), and Olson (1985). Olson (1985) AMEGHINO, F. 1894. Sur les oiseaux fossiles de Pata- refined the systematicplacement of this species gonie. Pp. 501-602 in Boletin del Instituto Geo- becauseAmeghino's illustrations of hypotarsal gr•phico Argentino, tomo XV, cuadernosXI y structure were sufficient to include it in the XII. [Published 1895.] Polyborinaeon the structureof the hypotarsus. BAUMEL,J. J., A. S. KING, A.M. LUCAS,J. E. BREAZILE, Ameghino (1894) reportedthe transversewidth & H. E. EVANS. 1979. Nomina anatomica avium. of the proximal articular end of the tarsometa- London, Academic Press. tarsusas 10 mm, nearly twice that of the com- BEC•

phylogenyof the Falconiformes,parts II-IV. Evol. zoic depositsin central Sioux County, western Theory 2: 115-208, 2: 209-300, 3: 1-141. Nebraska. Bull. Amer. Mus. Nat. Hist. 158: 265- KUROCHKIN,E.N. 1985. [Birdsof central Asia in the 371. Pliocene.]Trans. Joint Soviet-Mongolian Paleon- $TORER,R.W. 1982. Fused thoracic vertebrae in birds: tol. Expedition 26: 1-120. their occurrenceand possiblesignificance. J. Ya- LAMBRECHT, K. 1933. Handbuch der Palaeornithol- mashina Inst. Ornithol. 14: 86-95. ogie. Berlin, Verlag von Gebriider Borntraeger. SUSCHKIN,P. 1905. Zur Morphologie des Vogelske- MATTHEW, W. D. 1924. Third contribution to the lets. VergleichendeOsteologie der normalen Ta- Snake Creek Fauna. Bull. Amer. Mus. Nat. Hist. graubviSgel(Accipitres) und die Fragender Clas- 50: 59-210. sification. Nouv. Mem. Soc. Imp. Nat. Moscou MOURER-CHAUVIR][, C. 1982. Les oiseaux fossiles des 16(4): 1-247. Phosphoritesdu Quercy(•ocbne sup•rier a oli- TEDFORD, R. H., T. GALUSHA, M. F. SKINNER, B. E. goc•ne sup•rieur): implications pal•obiog•o- TAYLOR,R. W. FIELDS,J. R. MACDONALD, $. D. graphiques.Geobios m•m. sp•c. 6: 413-426. WEBB,•r D. P. WHISTLERßIn press. Faunal OLSON, S. L. 1976a. The affinities of the falconid successionand biochronologyof the Arikareean genusSpiziapteryx. Auk 93: 633-636. through Hemphillian interval (late ß 1976b. A new speciesof Milvago from His- through earliest Pliocene epochs),North Amer- paanola,with noteson other fossilcaracaras from ica. Berkeley, Univ. California Press. the West Indies (Aves: Falconidae). Proc. Biol. TONNI,E. P. 1980. The present state of knowledge Soc.Washington 88: 355-366. of the Cenozoicbirds of Argentina. Contrib. Sci. ß 1985. The fossil record of birds. Pp. 76-252 Nat. Hist. Mus. Los Angeles Co. 330: 105-114. in Avian biology, vol. 8 (D. S. Farner and J. King, TUGARINOV,A.J. 1935. [Some data on the Pliocene Eds.). New York, Academic Press. avifauna of Siberia.] Trudy Paleozoologichesko- PETERS,J.L. 1931. Check-list of birds of the world, go Instituta Akad. Nauk S.S.S.R.4: 79-89. vol. 1. Cambridge, Massachusetts,Harvard Univ. UMANSKAJA,A. $. 1981. [Miocene birds of the Black Press. Sea coastal region.] Miotsenovie ptitsy zapad- PORtIS,A. 1887. Contribuzioni alia ornitolitologia nogo prichernomorgya. U. [Ukrainian] S.S.R. Italiana, parte II. Mem. Accad. Rle. di Torino, SoobshchenyeII. Vest. Zool. 3: 17-21. classe di Sc. Fis. Mat. e Nat., ser. 2, 38: 181-203. VUILLEUMIER,F. 1970. Generic relations and specia- RIDGWAY,R. 1875. Studies of the American Falcon- tion patterns in the caracaras(Aves: Falconidae). idae. Monograph of the genus Micrastur. Proc. Breviora 355: 1-29. Acad. Nat. Sci. Philadelphia 1875:470-502. WETMORE, A. 1922. Remains of birds from caves in 1876. Studies of the American Falconidae. the Republic of Haiti. Smithsonian Misc. Coil. Monograph of the Polybori. Bull. Geol. Geo- 74(4): 1-4. graph. Surv. Territories,ser. 2, 6: 451-473, pl. 22- 1936. Two new speciesof hawks from the 25. Miocene of Nebraska. Proc. U.S. Natl. Mus. 84: SKINNER,M. F., S. M. SKINNER,& R. J. GOORIS. 1977. 73-78. Stratigraphy and biostratigraphy of late Ceno-