Volume 121/2 (July 2015)
Notice for subscribers:
pdf of papers published in the last 2 years are available on request to the Editorial Office.
ASTRAELENIA SAOMAMEDENSIS N. SP. - A NEW GIGANTIC RHYNCHONELLID SPECIES AND ITS PALAEOBIOGEOGRAPHICAL IMPLICATIONS FOR THE PORTALEGRE SYNCLINE (CENTRAL PORTUGAL)
MENA SCHEMM-GREGORY& JOSÉ M. PIÇARRA
A new species of Astraelenia is described from ?Siegenian to Emsian strata of the Portalegre Syncline (Central Portugal). Astraelenia saomamedensis n. sp. differs in a smaller number of costae, a rather inconspicuous fold and sulcus, and larger and elongate shells from other species of Astraelenia. Astraelenia occurs today in northern Africa, Central and Western Europe; the new species shows Gondwanan origin according to faunal elements found in the stratigraphic vicinity. The migration of Astraelenia is described considering Lower Devonian regional transgression and regression events. The new species is found in monospecific clusters and an attempt for understanding its palaeoecology is presented.
NEW DATA ON MIDDLE DEVONIAN CONODONTS FROM SW-SARDINIA:
THE SU NUARGI II SECTION REVISITED
The conodont collection from the nodular limestone beds of the Su Nuargi II outcrop near Domusnovas in SW-Sardinia (Italy) is restudied for the purpose of reassessing the outcrop and updating the conodont collection to the most recent taxonomy. Su Nuargi II is the most important outcrop in the SW of the island exposing Middle Devonian rocks. Forty-five conodont taxa have been identified in the collection, positioning the outcrop within the interval covering the timorensis to latifossatus zones (Lower to Middle Givetian) slightly widening the interpretation of Olivieri (1985). A new morphotype of Polygnathus linguiformis linguiformis is described. The genera Tortodus and Schmidtognathus are identified for the first time in the Middle Devonian of Sardinia. Additionally, a second Middle Devonian outcrop is discovered in the SW of the Island.
A NEW PERLEIDID FROM THE SPATHIAN (OLENEKIAN, EARLY TRIASSIC) OF CHAOHU, ANHUI PROVINCE, CHINA
ZUOYU SUN, ANDREA TINTORI, DAYONG JIANG & RYOSUKE MOTANI
A new actinopterygian genus and species, Chaohuperleidus primus gen. n. n. sp., is described from the Upper Member of the Nanlinghu Formation (Spathian, Olenekian, Early Triassic) at Majiashan (Majia Hill), Chaohu City, Anhui Province, Southeast China. The new taxon is assigned to the order Perleidiformes on the base of a combination of features: large wedge-like preoperculum with expanded infraorbital process and sensory canal running almost vertical along the posterior margin of the preoperculum itself, flank scalessomewhat higher than longer in the trunk region and presence of epaxial rays in the caudal fin.AmongPerleidiformes, the new taxonbelongsto thePerleididae, being very similar to Perleidus in the general body shape, pattern of the skull bones, the dentitionmade of peg-like marginal teeth,and number of epaxial rays. The new genus is characterized by the presence of a very large antero-dorsal process on the suboperculum, a high number (about 55) of transversal scale rows and dorsal and anal fin quite posterior. Chaohuperleidus gen. n., beingSpathianin age,represents the oldest record of the order Perleidiformes.
A NEW SPECIES OF SAURICHTHYS (ACTINOPTERYGII) FROM THE MIDDLE TRIASSIC (EARLY LADINIAN) OF THE NORTHERN GRIGNA MOUNTAIN (LOMBARDY, ITALY)
A new species of Saurichthys is described. It comes from an Early Ladinian fossil-bearing bed lying in the middle-lower part of the Buchenstein Formation on the Northern Grigna southern slope (Pasturo, Lecco). This new species differs from the several other Middle Triassic species in the remarkable size (more than 130 cm in length), in the presence of a grid structure made by the dorsal elements of its vertebral column, and in the posteriorly enlarging endoskeletal elements of both dorsal and anal fins. Moreover, only two longitudinal scale rows distinguish this taxon; together with the grid structure of the dorsal vertebral column, this character was previously observed only in Norian species (Late Triassic). The early appearance of these features in a Ladinian species opens a new, serious discussion on the evolutionary trends of Saurichthys , which is a very important genus, inhabiting the seas and lakes all over the world from the latest Permian to the end of the Triassic.
LADINIAN (MIDDLE TRIASSIC) SILICIFIED OSTRACOD FAUNAS FROM THE BALATON HIGHLAND (HUNGARY)
MIKLÓS MONOSTORI & EMŐKE TÓTH
Uniquely preserved and diverse ostracod faunas from Middle Triassic (Ladinian) beds of the Balaton Highland (Hungary) are described and figured. The preservation is due to silicification of fine texture of the carapaces and valves providing high quality data for taxonomical analyses. The benthic faunas from three localities (Litér, Felsőörs and Nemesvámos) consist of 28 taxa belonging to 12 genera. Four species are new: Polycope arcuatocosta n. sp., P. densoreticulata n. sp., Ptychobairdia tenuiornata n. sp. and Praemacrocypris literense n. sp. Based on morphological and ecological characteristics the studied benthic ostracod assemblages are the latest occurrences of the Thuringian-type assemblages sensu Becker. The dominance of the Thuringian-type elements, smooth bairdiaceans and metacopids indicates an open marine, more than 200 m deep, oligotrophic, bathyal environment with low energy conditions.
FIRST RECORD OF FOSSIL CYSTOPHORINAE (CARNIVORA, PHOCIDAE): MIDDLE MIOCENE SEALS FROM THE NORTHERN PARATETHYS
IRINA A. KORETSKY & SULMAN J. RAHMAT
Despite a long history of phocid studies, no fossil members of the Subfamily Cystophorinae have ever been described. New fossil material from the Middle Sarmatian (11.2-12.3 Ma) in the Paratethyan Basin of Ukraine allows emended diagnoses and redescriptions to help clarify phylogenetic relationships within the Family Phocidae. After cladistic and morphological analyses of the material, a new genus ( Pachyphoca ) was erected, with two new species of extinct fossil true seals ( Pachyphoca ukrainica and Pachyphoca chapskii ), belonging to the Subfamily Cystophorinae. This new material shows exceptional pachyosteosclerotic bones, which is uncommon for the family as a whole. The new Miocene genus shares numerous characters with several Recent species of Cystophora and Mirounga , providing the first opportunity to study sexual dimorphism of limb bones and mandibles in the Subfamily Cystophorinae. Sexual dimorphism in postcranial bones and mandibles in living members of Cystophorinae is more obvious than in other representatives of true seals. Examination of anatomical traits demonstrated that both new species are more primitive and better adapted for terrestrial locomotion than any living representatives of Cystophorinae. The smaller Pachyphoca ukrainica is more adapted to terrestrial locomotion than its larger relative, P . chapskii . Phylogenetic analysis suggests that seals with 10 incisors (Phocinae) are more primitive than those with 8 (Monachinae), and that Monachinae are more primitive than seals with 6 incisors (Cystophorinae).These findings indicate that the Subfamily Cystophorinae includes not only elephant and hooded seals, but also the two new Middle Sarmatian pachyosteosclerotic seals.
“PSEUDO-SARMATIAN” MOLLUSC ASSEMBLAGES FROM THE EARLY MESSINIAN OOLITE SHOALS OF SICILY (ITALY)
MATHIAS HARZHAUSER, MARKUS REUTER, OLEG MANDIC, SIMON SCHNEIDER, WERNER E. PILLER& MARCO BRANDANO
We present a revision of the Late Miocene mollusc assemblages from Faro Santa Croce (FSC) in SE Sicily. The FSC-section exposes lower Messinian coastal marine limestones of the Monte Carrubba Formation. Whilst the lowermost part is characterised by in situ occurrences of pen shells ( Atrina fragilis ), the larger part comprises cross-bedded oolites alternating with rock-forming cardiid-venerid coquinas. Due to their superficial similarity with Paratethyan Sarmatian assemblages, the taxa were partly identified as Sarmatian species in previous literature, resulting in a surprising diachronous occurrence of otherwise endemic Paratethyan species in the early Messinian Mediterranean Sea. Therefore, in respect to the ongoing discussion on Mediterranean-Paratethyan faunal exchange during Messinian times, a critical taxonomic re-evaluation of the mollusc assemblage appeared crucial for palaeo(bio)geographic interpretations. The revision of the fauna proofs the absence of any relations with the Sarmatian faunas of the Paratethys Sea; about 20% of the species from the Messinian part of the section are restricted to the Late Miocene and are typical Mediterranean elements. Similarly, no hint to lowered salinities can be deduced from the normal marine stenohaline assemblages. Their co-occurrence in oolitic shoals may rather point to somewhat hypersaline and alkaline settings in a strongly agitated environment.
THE SHELL ULTRASTRUCTURE OF THE GENUS GLYCYMERIS DA COSTA, 1778: A COMPARISON BETWEEN FOSSIL AND RECENT SPECIMENS
New data about the shell ultrastructure of species of the genus Glycymeris are obtained through a comparison between the fabric of recent specimens from Brittany (France) and fossil specimens collected from the Lower Pleistocene Castell’Arquato Formation cropping out along the Arda River in Western Emilia (Italy). This comparison, made using Scanning Electron Microscope (SEM), results in a strong similarity between the two fabrics, highlighting the good preservation of fossil ones. Both fossil and recent specimens show a well preserved outer simple crossed lamellar layer and an inner irregular and cone complex crossed lamellar layer. The inner and outer layers are separated by an irregular simple prismatic pallial myostracum. These mineralized layers are penetrated by parallel, not ramified and not bifurcated cylindrical tubules, which represent a peculiar character of the Arcoida shells. This analysis provides a more complete picture of Glycymeris shell ultrastructure. It shows that Glycymeris shell fabric has not changed for the last 2 million years and that the fossil specimens are pristine. Furthermore new data on the pattern and origin of tubules are reported, allowing to conclude that it is unlikely that they have a deterrence function for boring organisms. They may instead function to increase the volume of the organic content of the shell at lower metabolic cost without increasing the shell surface.
A MIOCENE ACERATHERIINE RHINOCEROTID (MAMMALIA, PERISSODACTYLA) FROM EARLY PLEISTOCENE MARINE DEPOSITS AT MONTE DELLE PICHE
(ROME, CENTRAL ITALY)
LUCA PANDOLFI, FRANCESCO GROSSI & VIRGILIO FREZZA
A fragmentary hemi-mandible of a rhinocerotid was collected during the end of the 19th century at Monte delle Piche (Rome). Morphological features, such as a short paralophid in the molar, the presence of a mesio-lingual cingulum in the teeth and a well-developed upturned I/2, indicate that the specimen is an Aceratheriinae. In addition to other taxa (e.g. Chilotherium, Aceratherium and Hoploaceratherium ), the hemi-mandible shows morphological traits suggestive of the genus Acerorhinus . The latter is well-documented in fossiliferous localities of South-eastern Europe, Turkey and China, chronologically related with the Land Mammal Zones MN 9-12. Unfortunately, the specimen is reworked in Early Pleistocene marine deposits.Hence, it cannot indicate the time at whichthe genus reached Italy.