Aliaga, new "symmetrodont" spalacotheriid mammal from Early Cretaceous of Spain

[Ben Creisler <bcreisler@gmail.com>]

Ben Creisler
bcreisler@gmail.com

In the new JVP:

Gloria Cuenca-Bescós, José I. Canudo, José M. Gasca, Miguel
Moreno-Azanza & Richard L. Cifelli (2014)
Spalacotheriid ‘symmetrodonts’ from the Early Cretaceous of Spain.
Journal of Vertebrate Paleontology 34(6): 1427-1436
DOI:10.1080/02724634.2014.866574
http://www.tandfonline.com/doi/full/10.1080/02724634.2014.866574

Spalacotheriids, basal trechnotheres with an acutely angled,
reversed-triangle pattern of major molar cusps, are relatively rare
pan-Laurasian mammals that ranged through much of the Cretaceous but
are generally not well represented in the fossil record. Herein we
describe newly collected specimens from the Molino Alto 1 locality,
Teruel Province, Spain, and review previously described materials from
the nearby locality of Galve; the sites lie in the same horizon in the
upper El Castellar Formation and are of early Barremian age. On this
basis, we recognize and name Aliaga molinensis, gen. et sp. nov., and
provisionally place in the same genus a previously described species,
cf. Aliaga henkeli, comb. nov., which appears to be the largest known
spalacotheriid. The two species are characterized by a distinctive,
multicuspate cingulid on lower cheek teeth. Based on acuteness of
molar cusp triangulation and other features (e.g., planar molar
shearing surfaces, elongation and cusp pattern of penultimate
premolar, reduction of last molar, simplification of upper molar crown
pattern), the species are referred to the Spalacolestinae. This
subfamily is most diverse in North America, where it ranged from
Albian–Campanian, but first appears in the Barremian of Western
Europe, supporting the hypothesis that the group had a Eurasian origin
and later dispersed to North America.