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Cretaceous anurans (new papers)

Ben Creisler

Some recent non-dino papers on Cretaceous anurans.

Márton Venczel , James D. Gardner, Vlad A. Codrea, Zoltán Csiki-Sava,
Stefan Vasile & Alexandru A. Solomon (2016)
New insights into Europe’s most diverse Late Cretaceous anuran
assemblage from the Maastrichtian of western Romania.
Palaeobiodiversity and Palaeoenvironments (advance online publication)
http: // link.springer.com/article/10.1007/s12549-015-0228-6

Uppermost Cretaceous (Maastrichtian) continental deposits in the
Transylvanian region of western Romania contain a diverse and
important assemblage of fossil vertebrates, including lissamphibians.
Bones of anurans (frogs) and albanerpetontids are abundantly
represented at multiple vertebrate microfossil localities in the
region, but there continues to be no evidence for urodeles
(salamanders) at any locality. Using previously reported and new
collections of isolated bones, here we provide an up-to-date and
comprehensive account of the anuran component of the Romanian
assemblage, with particular emphasis on new specimens exhibiting
features that are informative for differentiating species and
resolving their higher level affinities. We recognise at least five
species belonging to two or three families of moderately primitive
(i.e. non-neobatrachian), crown-clade anurans: the alytids Paralatonia
transylvanica, cf. Bakonybatrachus sp. and cf. Eodiscoglossus sp.; the
bombinatorid Hatzegobatrachus grigorescui; and an indeterminate,
possible pelobatid. Ilia previously reported as cf. Paradiscoglossus
(a monotypic alytid genus reliably known only from the Maastrichtian
of western North America) are here referred to Paralatonia. Also
present are indeterminate alytids and at least two potentially
distinctive, but indeterminate, taxa of uncertain family affinities.
New specimens allow Hatzegobatrachus, formerly regarded as incertae
sedis, to be assigned to Bombinatoridae as the geologically oldest
member of that family. The Romanian Maastrichtian anuran assemblage is
the most diverse yet documented for the European Late Cretaceous. It
contains a mix of endemic taxa (Paralatonia and Hatzegobatrachus), a
relict taxon (cf. Eodiscoglossus sp.), and one taxon (cf.
Bakonybatrachus) possibly resulting from a pre-Maastrichtian dispersal
from present-day Hungary. Compared to contemporaneous and older
(Santonian–Campanian) anuran assemblages elsewhere in Europe, the
Romanian assemblage is similar in containing alytids and a
pelobatid-like taxon, but differs in having more alytid taxa (n = 3)
and a bombinatorid, and in lacking the palaeobatrachids seen in the
Campanian–Maastrichtian of Western Europe and the probable ranoid
Hungarobatrachus reported from the Santonian of Hungary.

Hyogobatrachus & Tambabatrachus

Tadahiro Ikeda, Hidetoshi Ota & Masafumi Matsui (2016)
New fossil anurans from the Lower Cretaceous Sasayama Group of Hyogo
Prefecture, Western Honshu, Japan.
Cretaceous Research 61: 108-123
http: // www.sciencedirect.com/science/article/pii/S019566711530149X

We describe two well-preserved and articulated fossil anurans
excavated from the Lower Cretaceous Sasayama Group in Hyogo
Prefecture, Western Honshu, Japan, as new taxa on the basis of unique
combinations of character states. We performed a phylogenetic analysis
that included these new taxa, as well as Mesozoic and archaic anurans.
This analysis strongly supports the monophyly of each of the two new
taxa, both of which are placed in more derived positions than extant
leiopelmatids or Liaobatrachus from the Lower Cretaceous in China.
Anuran specimens from the Tetori Group of Japan are not assigned to
the two new taxa, suggesting that at least three anuran taxa were
present in Japan during the Early Cretaceous. These Japanese
representatives are not closely related to known fossil anurans from
Eastern Eurasia, unlike recently described Cretaceous lizards from
these two regions.


Pavel P. Skutschas & Veniamin V. Kolchanov (2016)
Anurans (Amphibia: Anura) from the Upper Cretaceous (Santonian–lower
Campanian) Bostobe Formation of Northeastern Aral Sea Region,
Palaeoworld (advance online publication)
http: // www.sciencedirect.com/science/article/pii/S1871174X16000196

The newly collected specimens from the Upper Cretaceous
(Santonian–early Campanian) Bostobe Formation at the Shakh-Shakh
locality in the Northeast Aral Sea Region, Kazakhstan, increase the
diversity of anurans in this stratigraphic unit and now two taxa can
be recognized there: gobiatid Gobiates sp. and large anuran
Discoglossidae indet. The faunal association of gobiatids +
discoglossids is characteristic for Cenomanian–Campanian vertebrate
assemblages of Middle Asia and Kazakhstan. In the Late Cretaceous of
Asia, large sized anurans appeared in the Cenomanian and became a
common element of anuran assemblages from the Turonian onwards,
earlier than in North America where large sized anurans began
dominating assemblages in the late Campanian.