The Auk 124(4):1294–1304, 2007 © The American Ornithologists’ Union, 2007. Printed in USA. A TODY (ALCEDINIFORMES: TODIDAE) FROM THE EARLY OLIGOCENE OF GERMANY Gea Ma1,3 an Chae W. Knf2 1Forschungsinstitut Senckenberg, Sektion Ornithologie, Senckenberganlage 25, D-60325 Frankfurt a.M., Germany; and 2Deutsches Krebsforschungszentrum, F030, Im Neuenheimer Feld 242, D-69120 Heidelberg, Germany Atat.—We describe a postcranial skeleton of a stem-group tody (Aves: Alcediniformes: Todidae) from the early Oligocene of Germany. The fossil is tenta- tively assigned to Palaeotodus itardiensis Mourer-Chauviré, 1985, which previously was known only from a few incomplete bones from the early Oligocene of France. It is the most substantial fossil record of a Paleogene stem-group tody described so far and shows many previously unknown skeletal details. The specimen confi rms the occurrence of Todidae, which are today restricted to the Caribbean Greater Antilles, in the Paleogene of Europe. The biogeographical signifi cance of these fi nds depends on the phylogenetic relationships between Todidae and other alcediniform birds. If Todidae are not the sister taxon of Momotidae (motmots) as suggested by a recent phylogenetic analysis of molecular data, occurrence of stem-group Todidae in the Old World fossil record actually follows from the currently assumed Old World ori- gin of alcediniform birds. Received 29 August 2006, accepted 19 November 2006. Key words: biogeography, evolution, fossil birds, Palaeotodus. Ein Todi (Alcediniformes: Todidae) aus dem unteren Oligozän Deutschlands Zaenfan.—Wir beschreiben ein postcraniales Skele eines Stamm gruppenvertreters der Todies (Aves, Alcediniformes, Todidae) aus dem frühen Oligozän von Deutschland. Das Fossil wird unter Vorbehalt Palaeotodus itardiensis Mourer-Chauviré, 1985 zugeordnet, einer Art, die bisher nur von wenigen unvollständigen Knochen aus dem frühen Oligozän von Frankreich bekannt war. Es ist der bisher vollständigste Fossilnachweis eines paläogenen Stammgruppenvertreters der Todies, und zeigt viele bisher unbekannte osteologische Einzelheiten. Das Exemplar bestätigt das Vorkommen von Todidae, die heute auf die karibischen Großen Antillen beschränkt sind, im Paläogen Europas. Die biogeographische Bedeutung dieser Funde hängt von den Verwandt- scha sbeziehungen zwischen Todies und anderen alcediniformen Vögeln ab. Falls Todies nicht das Schwestertaxon der Momotidae (Motmots) sind, wie eine kürzlich veröff entlichte phylogenetische Analyse molekularer Daten nahelegt, folgt das Vorkommen von Stammgruppenvertretern der Todidae in der Alten Welt vom gegenwärtig angenommenen altweltlichen Ursprung der alcediniformen Vögel. The five extant species of the alcediniform the evolutionary history of these birds, but it has todies (Todidae), which occur only on the Greater been recognized that their extant distribution Antilles, are very small, brightly colored, and is diff erent from that of the “total group” (pan- predominantly insectivorous birds that inhabit monophylum, i.e., the clade including stem- and various kinds of woodlands, from rainforests to crown-group representatives), because all fossil arid brush (Kepler 2001). Li le is known about stem-group representatives were found far out- side the Caribbean region. The fi rst fossil record of the Todidae was 3E-mail: [email protected] identifi ed by Olson (1976), who described the 1294 October 2007] Oligocene Tody from Germany 1295 stem-group tody Palaeotodus emryi from the previously unknown osteological details of this early Oligocene Brule Formation in Wyoming taxon. (~30 mya; Olson 1976). The original description of P. emryi was based on a skull and the proxi- Mateia an Meth mal portion of a humerus only, and although postcranial remains of another individual of Osteological terminology follows Baumel and this species, from the lowest part of the Brule Witmer (1993). Measurements are in millimeters Formation, exist in the collection of the National and, unless indicated otherwise, represent the Museum of Natural History in Washington, maximum length of the bones along their lon- D.C., these have not yet been described. The gitudinal axis; the ungual phalanges were mea- humerus of the holotype of P. emryi is pro- sured from the tip to the processus extensorius. portionally larger than that of extant Todidae, Institutional abbreviations are as follows: SMF = and Olson (1976:114) hypothesized that “in Forschungsinstitut Senckenberg, Frankfurt am the Oligocene, the Todidae were possibly more Main, Germany; USNM = National Museum of diverse than at present and probably included Natural History, Washington, D.C. larger, more actively fl ying forms with be er developed wings than the strictly sedentary Systematic Paleontology modern todies.” Tody fossils are also known from the Old Alcediniformes (sensu Mayr 1998) World: two species of Palaeotodus, P. escamp- Todidae Vigors, 1825 siensis and P. itardiensis, were reported by Palaeotodus Olson, 1976 Mourer-Chauviré (1985) from the Late Eocene Palaeotodus cf. itardiensis Mourer-Chauviré, 1985 (P. escampsiensis: Mammalian Paleogene [MP] stratigraphic level 19, i.e., 35 mya) and early Referred specimen.—SMF Av 505: disarticu- Oligocene (P. itardiensis: MP 23, i.e., 31 mya) of lated skeleton on a slab, lacking skull and le France. Palaeotodus itardiensis is similar in size to wing (Fig. 1); the counter-slab is transferred on P. emryi and distinctly larger than extant todies, the same resin slab but contains very few bone but the crown-group tody-sized P. escampsien- fragments. sis shows that some Paleogene stem-group Locality and horizon.—Frauenweiler south Todidae were as small as their extant relatives. of Wiesloch (Baden-Wür emberg, Germany), Unfortunately, these Old World species of former clay pit of the Bo -Eder GmbH (“Grube Palaeotodus, which apparently were overlooked Unterfeld”), Rupelian, Lower Oligocene by Overton and Rhoads (2004), are known from (Micklich and Hildebrandt 2005). only a few bones: the description of P. escamp- Measurements.—Numbers in parentheses are siensis is based on an incomplete humerus, and measurements of an undescribed specimen that of P. itardiensis on a proximal ulna, distal (USNM 334940) of P. emryi. Coracoid, 14.8 (le ). tibiotarsus, and proximal tarsometatarsus. Sternum (spina externa to trabecula intermedia), Thus, the morphology of Paleogene stem-group ~15.8. Humerus, 19.2 (right) (20.9). Ulna, 24.7 Todidae is still very incompletely known, which (right) (26.7). Carpometacarpus, 10.0 (right) severely limits comparisons with crown-group (10.1). Femur, 15.3 (right) (16.6). Tibiotarsus, Todidae on the one hand and between the 23.4 (le ), 23.4 (right) (24.9). Tarsometatarsus, North American and European fossil species 16.5 (le ), 16.6 (right) (>14.7). Pedal phalanges on the other. (le /right): I1, 4.5/4.3; I2, –/3.3; II1, 2.7/–; II2, Here, we describe a postcranial skeleton of 3.2/–; II3, 2.5/2.5; III1, 3.9/–; III2, 3.8/–; III3, 3.6/ Palaeotodus from the Lower Oligocene (MP 22, 3.7; III4, –/3.5; IV1, 2.7/–; IV4, –/2.2; IV5, –/2.4. i.e., 32 mya; Micklich and Hildebrandt 2005) of Remarks on phylogenetic assignment.— Frauenweiler in Southern Germany, a former Classifi cation of the Frauenweiler fossil clay pit whose marine, near-shore deposits have into Alcediniformes (i.e., a clade including yielded several other avian taxa (Mayr 2000, todies, motmots [Momotidae], kingfi shers 2004a, b, 2005a, 2006b; Mayr et al. 2002; Mayr [Alcedinidae], and bee-eaters [Meropidae]) is and Manegold 2004, 2006). This specimen is supported by the following derived features: the most completely preserved fossil record of (1) distal end of ulna with very large condylus Palaeotodus and allows the recognition of many dorsalis (except Meropidae); (2) os metacarpale 1296 Mayr and Knopf [Auk, Vol. 124 Fig. 1. Palaeotodus cf. itardiensis Mourer-Chauviré, 1985, from the Lower Oligocene of Frauenweiler, Germany (SMF Av 505). (A) Sternum, shoulder girdle, and right wing with interpre- tive drawing. (B) Pelvis and feet with interpretive drawing. Abbreviations: fur = furcula, lco = left coracoid, lfe = left femur, lsc = left scapula, ltb = left tibiotarsus, ltm = left tarsometatarsus, ocu = os carpi ulnare, pdm = phalanx distalis digiti majoris, pel = pelvis, ppm = phalanx proximalis digiti majoris, r = rib, rcm = right carpometacarpus, rfe = right femur, rhu = right humerus, rra = right radius, rtb = right tibiotarsus, rtm = right tarsometatarsus, rul = right ulna, st = sternum, v = vertebra. Coated with ammonium chloride to enhance contrast. Scale bars equal 5 mm. minus of carpometacarpus protruding distally derived characters with crown-group Todidae: far beyond os metacarpale majus (Mayr 1998); (1) scapi clavicularum of furcula very thin; (2) (3) trochleae metatarsorum cylindrical and on the proximal end of humerus reaching far ventrally same dorsoplantar level (Mayr 1998); and (4) and infl ected so that almost entire caput humeri proximal phalanx of hallux with (albeit small) situated farther ventrally than ventral margin of lateral projection (Mayr 1998). sha ; (3) carpometacarpus with large processus The specimen agrees with extant Momotidae intermetacarpalis; (4) tarsometatarsus greatly and Todidae but diff ers from Alcedinidae and elongated and slender, measuring almost the Meropidae in its long hindlimbs and the com- length of the humerus; and (5) plantar surface plete reduction of the processus procoracoideus of trochlea metatarsi III bearing a marked sulcus. of the coracoid; it further
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