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| Psammophis odysseus Georgalis & Szyndlar, 2022 |
Abstract
We here describe abundant new snake material from the late Miocene (MN 13) of Salobreña, Spain. Vertebral morphology suggests a referral of the specimens to the extant psammophiid Psammophis, documenting the first occurrence of this genus in Europe. The diversity and disparity across the vertebral morphology of different psammophiid genera are discussed. We identify vertebral features that could diagnose Psammophis and therefore enable the recognition of the genus in the fossil record. A comparison of the new Spanish form with other taxa is conducted. We provide a detailed review of the psammophiid fossil record. Material previously described from the middle Miocene of Beni Mellal, Morocco is here tentatively referred to as ?Psammophis sp., an action that renders that occurrence as the oldest (probable) record of the genus and Psammophiidae as a whole, providing thus a potential calibration point. On the other hand, Eastern European Pliocene material that had been previously supposedly referred to Psammophis is here discarded as being rather fragmentary, not affording any more precise determination. The two psammophiid genera Psammophis and Malpolon appear almost simultaneously in the European fossil record (MN 13), with the former achieving only a short-lived and apparently geographically limited distribution in the continent, while the latter still exists in its modern herpetofauna. We assess biogeographic implications of the new find, suggesting a direct dispersal event from northwestern Africa to the Iberian Peninsula during the late Miocene, facilitated by the Messinian Salinity Crisis.
Keywords: biogeography, Messinian Salinity Crisis, Psammophiidae, Serpentes, vertebral morphology
Systematic paleontology
Squamata Oppel, 1811
Serpentes Linnaeus, 1758
Alethinophidia Nopcsa, 1923
Caenophidia Hoffstetter, 1939
Colubroides Zaher, Grazziotin, Cadle, Murphy, Cesar de Moura-Leite and Bonatto, 2009
Colubriformes Zaher, Grazziotin, Cadle, Murphy, Cesar de Moura-Leite and Bonatto, 2009
Elapoidea Vidal, Delmas, David, Cruaud, Couloux and Hedges, 2007
Psammophiidae Bourgeois, 1968
Psammophis Boié in Fitzinger, 1826
Psammophis odysseus sp. nov.
Type locality. Late Miocene (MN 13, Messinian) of Salobreña, Andalusia, Spain.
Etymology. From the Greek mythical hero Odysseus (Ὀδυσσεύς), who, in Homer's “Odyssey” (Ὀδύσσεια), extensively traveled and wandered the seas for 10 years on his way back home after the fall of Troy; during his long voyage, Odysseus visited multiple places but never settled permanently in any of them, eventually finally reaching his homeland Ithaca. The name alludes to the dispersal of Psammophis from northwestern Africa to Iberia, which could potentially have even included also some overseas rafting, as well as its temporary only “stay” in the “new land” of Europe. Gender is masculine.
CONCLUSION:
We describe a new species of psammophiid snakes, Psammophis odysseus sp. nov., based on abundant vertebral material from the late Miocene (MN 13) Salobreña, Spain. This represents the first documented occurrence of Psammophis in Europe, adding to the considerably poor diversity of psammophiids in the continent. A thorough discussion of the vertebral morphology and intracolumnar variation of extant psammophiids is provided, coupled with detailed figuring of selected extant taxa. We identify vertebral features that could serve as diagnostic for Psammophis.
The fossil record of psammophiid snakes is thoroughly reviewed. Taking into consideration the age, geographic location, and faunal composition of Salobreña, we imply that Psammophis odysseus sp. nov. most likely dispersed from northwestern Africa to Iberia, taking advantage of the environmental perturbations of the Messinian Salinity Crisis, but the genus eventually did not manage to settle in Europe and became subsequently extinct from the continent.
Georgios L. Georgalis and Zbigniew Szyndlar. 2022. First Occurrence of Psammophis (Serpentes) from Europe witnesses Another Messinian Herpetofaunal Dispersal from Africa – Biogeographic Implications and A Discussion of the Vertebral Morphology of Psammophiid Snakes. The Anatomical Record. DOI: 10.1002/ar.24892
