Pelecanus paranensis sp. nov. (1 Viewer)

[Fred Ruhe]

Jorge I. Noriega, Marcos Cenizo, Diego Brandoni, Leandro M. Perez, David E. Tineo, Juan M. Diederle & Paula Bona, 2023
,
A new pelican (Aves: Pelecanidae) from the Upper Miocene of Argentina: new clues about the origin of the New World lineages

Journal of Vertebrate Paleontology, 0 (0): e2202702.
doi:10.1080/02724634.2023.2202702. ISSN 0272-4634

ABSTRACT: https://www.tandfonline.com/doi/abs/10.1080/02724634.2023.2202702?journalCode=ujvp20

Pelecanus paranensis sp. nov., a new pelican (Aves, Pelecanidae) from the marine Upper Miocene Paraná Formation, which crops out in the Province of Entre Ríos, Argentina, is described. This record constitutes the first report of a fossil pelican from Argentina and the southernmost from South America. The holotypical specimen consists of a very large and nearly complete pelvis, which is characterized by having the cristae iliacae dorsales continuous throughout its entire length and a large foramen acetabuli. The U-shaped morphology of the postacetabular section of the pelvis of the new species as well as the wide incisura sutura iliosynsacralis, allow to infer its phylogenetic position within the New World pelican species clade, showing a close relationship with the clade (P. occidentalis + P. thagus). A probable trans-Atlantic dispersal route for the ancestor of the New World pelicans is thus inferred. The inland Paranaense Sea, which flooded the South American Chaco-Paraná basin during the mid-Neogene, is proposed as a south-north pathway for ancestral forms of the clade (P. occidentalis + P. thagus). These regressive marine paleoenvironments of the Late Miocene may have acted as the evolutionary driver for the transition of pelican species from brackish or freshwater habitats to those inhabiting strictly marine coastlines.

Enjoy,

Fred

 

[Fred Ruhe]

SYSTEMATIC PALEONTOLOGY

Class AVES Linnaeus, 1758
Clade AEQUORNITHES Mayr, 2011
Order PELECANIFORMES Sharpe, 1891
Family PELECANIDAE Rafinesque, 1815
Genus PELECANUS Linnaeus, 1758

PELECANUS PARANENSIS, sp. nov.

Holotype—A nearly complete pelvis, CICYTTP-PV-A-3-277

Etymology—paranensis, from the Paraná Formation, i.e., the stratigraphic provenance of the holotype.

Diagnosis—(1) large-sized species; (2) facies articularis cranialis of first fused vertebra thoracica compressed dorsoventrally; (3) processus transversales of three most cranial fused vertebrae thoracicae wide; (4) gap present between ala preacetabularis ilii and processus transversalis of third fused vertebra thoracica; (5) alae preacetabulares ilii strongly curved laterally; (6) planum transversalium and surface between cristae iliacae dorsales wide; (7) crista spinosa synsacralis robust, emerging cranially to alae preacetabulares ilii; (8) processus antitrochantericus not prominent; (9) cristae iliacae dorsales continuous throughout entire length (i.e., without flat notch for attachment of musculus
iliotrochantericus caudalis); (10) postacetabular dorsocaudal section of pelvis U-shaped (i.e., crista iliaca dorsolateralis weak, blunt, and medially curved, caudally abbreviated and reduced to ridge; see below); (11) incisura sutura iliosynsacralis wide and shallow; (12) bulla intumescentia lumbosacralis slender; (13) processus costalis of last synostotic vertebra thoracica (i.e., eighth vertebra thoracica) stout and wide; (14) pila ilioischiadica short; (15) pars ischiadica of fossae renales quadrangular, narrow, and elongated craniocaudally; (16) caudal section of postacetabular synsacrum robust, lacking longitudinal crista; (17) foramen acetabuli large; (18) lamina infracristalis ilii expanded dorsoventrally; (19) foramen ilioischiadicum subelliptical.

Differential Diagnosis—Differs from P. occidentalis in characters (1), (2), (8), (12), (13), (14), and (15); from P. thagus in (2), (4), (8), (12), (13), (14), (15), and (16); from P. erythrorhynchos in (3), (6), (7), (10), (11), (15), (16), and (18); from P. onocrotalus in (4), (5), (6), (8), (10), (11), (15), and (16); from P. conspicillatus in (4), (5), (6), (8), (10), (11), (15), (16), and (18); from P. rufescens in (1), (4), (5), (6), (8), (10), (11), (16), and (18); from P. philippensis in (1), (3), (4), (5), (6), (8), (10),
(11), (15), (16), (18), and (19); and from P. crispus in (1), (4), (5), (6), (8), (10), (11), (16), (18), and (19). The characters (9) and (17) are putative autapomorphies of the new species.

Locality and Horizon—The material comes from Cerro La Matanza locality (32°35′51′′S, 60°11′22′′W) in Victoria City, Entre Ríos Province, Argentina, from the upper sandstone marine beds of the Paraná Formation (Fig. 1). Radiometric and biochronological data indicate that the age of the Paraná Formation corresponds to the Late Miocene (Tortonian–Messinian stage).

Fred


FIGURE 1. Nearly complete pelvis of Pelecanus paranensis (CICYTTP-PV-A-3-277) from Upper Miocene marine strata of Paraná Formation in Cerro La Matanza locality (Entre Ríos Province, Argentina). Holotype in dorsal (A), ventral (B), right (C), and left (D) views. Scale bar equals 50 mm.