A relict tropical forest bat assemblage from the early Miocene of the Ribesalbes-Alcora Basin (Castelló, Spain)

Abstract

We present the bat assemblage from the early Miocene (MN4, 16.9–15.95 MY) basin of Ribesalbes-Alcora, which has yielded the remains of ten chiropteran taxa. Bat assemblages are rarely recovered in the fluvio-lacustrine fossil record. A bat species described in this work, Cuvierimops penalveri sp. nov., is a new form of a typically Oligocene free-tailed bat. In addition, the other molossids Hydromops helveticus, Rhizomops cf. brasiliensis, Chaerephon sp., Tadarida sp., and the vespertilionids Myotis cf. intermedius and Miostrellus aff. petersbuchensis, as well as undetermined fossils ascribed to the genera Submyotodon, Plecotus, and Rhinolophus are described. This is the first record of the genus Rhizomops in the early Miocene; the genus Cuvierimops is the first recording from the Neogene, while the ‘Lazarus taxon’ Chaerephon is the first fossil record of this genus, registered previously only in Holocene deposits. This bat assemblage with a high abundance of molossids is typical from the early Oligocene of western Europe, while in the early Miocene from Europe the molossids are scarce. The abundance of these bats is consistent with the presence of a tropical forest surrounding a paleolake. The fossils from the Ribesalbes-Alcora Basin represent the most complete bat assemblage of the Iberian Peninsula during this age, and significantly increase our knowledge about the early Miocene bats of Europe.

Taxonomy and Affinities of African Cenozoic Metatherians

“…While the M1 has a small hypocone that disconnects the postptotocrista to the metacone, in the M2 this appears connected to the metacone, similar to Miostrellus aff. petersbuchensis Rosina & Rummel, 2012 described by Crespo et al (2020). This combination of features does not appear in other vespertilionid or myzopodid bats from the Eocene.…”

“…To us, the upper molars described in Sánchez-Villagra et al (2007) have several features that characterize chiropteran species of the Vespertilionidae and Myzopodidae, as Myotis, Pipistrellus or Miostrellus, in the former, or Myzopoda in the second. These features include the shape of the protocone, absence of talon, well-developed mesial and posterior cinguli, M2 having a small hypocone, among other features (Gunnell et al, 2014;Crespo et al, 2018Crespo et al, , 2020. Notwithstanding, these materials also have unique features, as the connection of the preprotocrista with the paracone, which is disconnected to the paracingulum.…”

First study of the bat fossil record of the mid-Atlantic volcanic islands

“…The method of dental nomenclature is from Crespo et al . (2020) and the humerus nomenclature is from Salles et al . (2014).…”

Clarendonian (Late Miocene) Bats (Chiroptera, Vespertilionidae and Molossidae) From the Ogallala Formation, High Plains of Oklahoma, Usa

“…brasiliensis (as described by Crespo et al, 2020) and from Miocene Australian Petramops creaseri (as described by Hand, 1990) in having a long paraloph extending toward the protocone and short metaloph extending to the postprotocrista. (Note that there is as yet no consensus among authors investigating molossid phylogeny [e.g., Freeman, 1981; Legendre, 1984 a , 1984 b , 1985; Sudman et al, 1994; Ammerman et al, 2012, 2013] that could serve as a basis for a stable taxonomy, and that some authors differ in their use of Tadarida and Rhizomops for the taxon brasiliensis [Legendre, 1984 a , 1985; Owen et al, 1990; Ammerman et al, 2012; Maitre, 2014; Crespo et al, 2020]; resolution of that discussion is beyond the scope of this note.) The p4 differs from most recent molossid genera in having a stronger anterolingual cingular cusp and the posteriorly hooked main cusp, although these structures might prove to be variable in their development across large samples or geographic regions.…”

“…Other abbreviations used in text: Ma, megannum, or millions of years ago (Woodburne, 2006); TxVP, Texas Vertebrate Paleontology Collections, University of Texas Jackson School Museum of Earth History, Austin, including specimens from the Whisenhunt Quarry collected by Walter W. Dalquest and graduate students previously at Midwestern State University, Wichita Falls, Texas. Dental and postcranial osteological terminology follow Vaughan (1959), Gunnell and Manthi (2020), Crespo et al (2020), and Gaudioso et al (2020). We measured specimens to the nearest 0.01 mm using an ocular micrometer reticle on an Olympus SZX9 zoom stereomicroscope (Olympus America Inc., Mellville, New York) calibrated with a stage micrometer slide, following Sevilla García (1988:Fig.…”