Salvador Bailon

The rediscovered Hula painted frog is a living fossil

Amphibian declines are seen as an indicator of the onset of a sixth mass extinction of life on earth. Because of a combination of factors such as habitat destruction, emerging pathogens and pollutants, over 156 amphibian species have not been seen for several decades, and 34 of these were listed as extinct by 2004. Here we report the rediscovery of the Hula painted frog, the first amphibian to have been declared extinct. We provide evidence that not only has this species survived undetected in its type locality for almost 60 years but also that it is a surviving member of an otherwise extinct genus of alytid frogs, Latonia, known only as fossils from Oligocene to Pleistocene in Europe. The survival of this living fossil is a striking example of resilience to severe habitat degradation during the past century by an amphibian.

The Late Pliocene amphibians and reptiles from Capo Mannu D1 Local Fauna (Mandriola, Sardinia, Italy)

ABSTRACT The Late Pliocene Capo Mannu D1 Local Fauna (Mandriola, W Sardinia, Italy) produced remains of five amphibians and at least nine reptiles: Salamandrina sp., cf. Ichthyosaura sp., Discoglossus sp., cf. Bufo gr. B. viridis Laurenti, 1768, Hyla gr. H. arborea (Linnaeus, 1758), Gekkonidae indet., Dopasia sp., Lacerta gr. L. viridis (Laurenti, 1768), Lacertidae indet. (small size), Amphisbaenia indet., Eryx cf. E. jaculus (Linnaeus, 1758), Colubrinae indet., Natrix sp., and Vipera sp. The Capo Mannu D1 assemblage partly fills a chronological gap in the knowledge of the Sardinian herpetofauna because well-diversified herpetofaunas have been retrieved only in the Early Miocene of Oschiri and in the Pleistocene of Monte Tuttavista. It has an intermediate taxonomic composition and still shows a high rate of taxa which are now extinct on the island (Salamandrina sp., cf. Ichthyosaura sp., Dopasia sp., Lacerta gr. L. viridis, Amphisbaenia indet., Eryx cf. E. jaculus, and Vipera sp.). Some taxa (both extinct and extant) are present in the three localities but none is exclusively shared by Oschiri and Monte Tuttavista. The remains of Salamandrina from the Capo Mannu D1 Local Fauna testify for a prolonged permanence in Sardinia of this taxon (already known from Oschiri). The absence of remains unambiguously referable to the previously reported ranids could suggest that these anurans never reached the island by natural dispersal (without human intervention). The taxonomic composition of the Capo Mannu D1 Local Fauna is overall similar to that of other west Mediterranean Pliocene herpetofaunas, and it confirms the previously reported pattern of evolution of European herpetofaunas.

Combining Small-Vertebrate, Marine and Stable-Isotope Data to Reconstruct Past Environments

Three very different records are combined here to reconstruct the evolution of environments in the Cantabrian Region during the Upper Pleistocene, covering ~35.000 years. Two of these records come from Antoliñako Koba (Bizkaia, Spain), an exceptional prehistoric deposit comprising 9 chrono-cultural units (Aurignacian to Epipaleolithic). The palaeoecological signal of small-vertebrate communities and red deer stable-isotope data (δ13C and δ15N) from this mainland site are contrasted to marine microfaunal evidence (planktonic and benthic foraminifers, ostracods and δ18O data) gathered at the southern Bay of Biscay. Many radiocarbon dates for the Antoliña’s sequence, made it possible to compare the different proxies among them and with other well-known North-Atlantic records. Cooling and warming events regionally recorded, mostly coincide with the climatic evolution of the Upper Pleistocene in the north hemisphere.

Late Miocene/Early Pliocene vertebrate fauna from Mallorca (Balearic Islands, Western Mediterranean): An update

The vertebrate fossil record from the Balearic Islands (western Mediterranean) has improved considerably over the past decade, especially in Mallorca and Menorca. In Menorca, the Pliocene terrestrial fauna was updated by the discovery and description of the large-sized leporid Nuralagus, several reptiles and an amphibian. In Mallorca, paleontological exploration yielded 2 deposits with a Late Miocene/Early Pliocene chronology, Caló den Rafelino (CdR) and Na Burguesa-1 (NB-1). So far, 4 new mammalian taxa and 2 new reptiles have been identified for the CdR deposit, whereas the faunal assemblage from the recently discovered deposit (Apr 2012) of NB-1 is currently composed of, at least, 6 terrestrial mammals, 8 reptiles and an amphibian. Its faunal composition and some primitive characteristics of the obtained taxa suggest that the chronology of this deposit is slightly earlier than the CdR. The terrestrial vertebrates recorded in these 2 Mallorcan deposits are changing the view of the paleofaunal assemblage previously known for the Plio-Pleistocene of the island. Morphological characteristics displayed by some of the taxa suggest that these faunas would be at the beginning of an isolated evolution. In this paper we present a preliminary report on the fossils recovered from the NB-1 deposit, as well as some unpublished data from CdR, and we analyze the whole fauna from both Mallorcan deposits, focusing on taxonomical and paleobiogeographical aspects.

Amphibia and Squamata

The Pliocene of Laetoli (Tanzania) has produced a taxonomically unbalanced fauna of amphibians and squamate reptiles. Amphibians are represented by only two specimens belonging to indeterminate anurans. Similarly, lizards are comprised of two specimens that are referred to an indeterminate acrodontan and an indeterminate scincomorphan. Snakes are more numerous (more than 150 specimens) and taxonomically diverse. They include a boid (Python sebae or P. natalensis), at least three colubrids (cf. Thelotornis, cf. Rhamphiophis, one indeterminate colubrid, and another indeterminate taxon that might be a modern specimen), an elapid (Naja robusta), a possible distinct elapid, and a viperid (Bitis olduvaiensis or a new species of Bitis). The latter taxon represents the most common snake. The paleoecological implications of the fauna are not readily apparent because the most useful indicator taxa are distributed in different beds. Based on the entire fauna it may be concluded that the Laetoli area was neither a desert nor covered by forest. Bodies of water were periodically present, at least during the period of deposition of the Upper Laetolil Beds. An unusual feature of the Laetoli snake community, but similar to a few other Neogene faunas from sub-Saharan Africa, is the fact that colubrids are not the dominant taxon.

First fossil representative of the salamander crown-group from a Gondwanan continent:Pleurodeles cf. waltl from the Quaternary of Morocco

No fossil belonging to the Caudata crown-group has been hitherto described from a former Gondwanan continent. We report the first known extinct member of the caudate crown-clade from Africa, i.e. a Gondwanan territory. It belongs to the Recent genus Pleurodeles (Salamandridae) and is referred to as Pleurodeles cf. waltl . The fossils come from the Pleistocene of Morocco. They show that Pleurodeles (likely P. waltl ) has been present in Africa for at least two million years and that anthropogenic dispersal is not the cause of its presence in this continent.

Maioricalacerta rafelinensis, gen. et sp. nov. (Squamata, Lacertidae), from the early Pliocene of Mallorca (Balearic Islands, western Mediterranean Sea)

ABSTRACT Here we describe a new genus and species of Lacertidae, Maioricalacerta rafelinensis, gen. et sp. nov, a largesized lizard with amblyodont teeth from the early Pliocene (Zanclean) of Mallorca (Balearic Islands, western Mediterranean Sea). The presence of amblyodont teeth separates Maioricalacerta from recent species of Lacertidae. Maioricalacerta differs from the amblyodont lacertids of the European Tertiary (Quercycerta, Escampcerta, Mediolacerta, Pseudeumeces, Dracaenosaurus, Amblyolacerta, and Ligerosaurus) in the anteroposterior and mediolateral widening of the teeth and in the wide lateral wall of the dentary, which is massive, relatively short, and robust. Dracaenosaurus displays a similar morphology of the dentary, but the number of teeth is lower and they are more amblyodont than in Maioricalacerta. The dentition observed in Maioricalacerta suggests that the diet of the species was related to a consumption of hard prey, perhaps molluscs. The length reduction of the dentary constitutes an evolutionary biomechanical advantage to consume this kind of prey as it improves jaw-closing force. However, its movement is likely to have been slower but potentially more accurate. The robustness of the dental structures in Maioricalacerta also contributes to enhance the resistance of the bone against the increased static pressure to which it is subjected during jaw closure. Maioricalacerta is the most Recent amblyodont lacertid known and the only one described from the Pliocene of Europe.

A fossil Diploglossus (Squamata, Anguidae) lizard from Basse-Terre and Grande-Terre Islands (Guadeloupe, French West Indies).

Today, Diploglossine lizards (Anguidae) are common on the Greater Antillean Islands (West Indies), where they are represented by many endemic species. However these lizards are very rare on the Lesser Antillean Islands, where they are only represented by a single species, the Montserrat galliwasp (Diploglossus montisserrati). Here, we show that diploglossine lizards were present in the past on other Lesser Antillean islands, by reporting the discovery of Anguidae fossil remains in two Amerindian archaeological deposits and in a modern deposit. These remains are compared to skeletons of extant diploglossine lizards, including D. montisserrati, using X-ray microtomography of the type specimen of this critically endangered lizard. We also conducted a histological study of the osteoderms in order to estimate the putative age of the specimen. Our results show that the fossil specimens correspond to a member of the Diploglossus genus presenting strong similarities, but also minor morphological differences with D. montisserrati, although we postulate that these differences are not sufficient to warrant the description of a new species. These specimens, identified as Diploglossus sp., provide a new comparison point for the study of fossil diploglossine lizards and reflect the historical 17th century mentions of anguid lizards, which had not been observed since.

Osteological Observations on the Alytid Anura Latonia nigriventer with Comments on Functional Morphology, Biogeography, and Evolutionary History

The Hula Painted Frog (Latonia nigriventer) is a rare frog species endemic to the Hula Valley, Israel. The species is the sole relict of a clade that was widespread mainly in Europe from the Oligocene until the beginning of the Pleistocene. The osteological characteristics of L. nigriventer are described based on X‐ray microtomography scans of extant specimens and Pleistocene bones from the Hula Valley, to elucidate the evolutionary history of Alytidae and more specifically of Latonia. Based on the osteological description of L. nigriventer, we now better understand the differences, between Latonia and its sister taxon Discoglossus. They differ mainly in their cranial structure with the reinforced skull of Latonia having powerful jaws. Latonia nigriventer can achieve great force while closing its jaws, due to increased adductor muscle insertion surfaces as expressed by the presence of an additional paracoronoid process and an enlarged upper margin of the postero‐lateral wall of the lower jaw. In addition, a wider pterygoid fossa and higher canthus postero‐lateralis of the frontoparietal, compared to that of Discoglossus, also suggest the presence of well‐developed adductor muscles. Furthermore, L. nigriventer have particularly strong skulls as expressed by: long articulations between different skull elements, interdigitation in the contact area between the nasals and between nasals and the frontoparietals, and fused frontoparietals. Both males and females L. nigriventer have very robust forelimbs, as indicated by well‐developed medial crests of the humerus. Based on limited eastern Mediterranean paleontological data, we can only suspect that the dispersal of Latonia into the Levant from Asia Minor occurred at some point during the Miocene or later. The first appearance of L. nigriventer in the Hula Valley, its current habitat, dates to approximately 780 thousand years ago at the archaeological site of Gesher Benot Ya‘aqov. J. Morphol. 277:1131–1145, 2016.

Human impacts reduce morphological diversity in an insular species of lizard

Fossil remains provide useful insights into the long-term impact of anthropogenic phenomena on faunas and are often used to reveal the local (extirpations) or global (extinctions) losses of populations or species. However, other phenomena such as minor morphological changes can remain inconspicuous in the fossil record depending on the methodology used. In this study, we used the anole of Marie-Galante Island (Anolis ferreus) in Guadeloupe (French, West Indies) as a model to demonstrate how the morphological evolution of an insular lizard can be tracked through the Pleistocene/Holocene climatic transition and the recent anthropization of the island. We used a fossil assemblage of nearly 30 000 remains and a combination of anatomical description, traditional morphometry and geometric morphometrics. These fossils are attributed to a single taxon, most likely to be A. ferreus on the basis of morphological and morphometric arguments. Our results show the disappearance of a distinct (sub)population of large specimens that were about 25% larger than the modern representatives of A. ferreus. We also demonstrate an apparent size stability of the main fossil population of this species since the Late Pleistocene but with the possible occurrence of a reduction in morphological diversity during the Late Holocene. These results highlight the impact of anthropic disturbances on a lizard whose morphology otherwise remained stable since the Late Pleistocene.