EXPANDING THE RECORD OF LARVAE OF FALSE FLOWER BEETLES WITH PROMINENT TERMINAL ENDS

Beetle larvae contribute to the overall biomass with a great share, yet they often stay unnoticed and underexplored. Larvae of the group Scraptiidae, also called false flower beetles, lead a life hidden in the wood, not easily accessible for observers. There, they contribute to wood decomposition and carbon cycling. Even though their ecological role is of great importance, these larvae have been comparably rarely studied. This is true for extant as well as fossil representatives of this group. It seems that this knowledge gap is not based on the limited availability of material but results from insufficiently studied material. Here we report new specimens, of which seven are extant and twelve are fossil. Fossil specimens are either from 40-million-year-old Baltic amber (Eocene) or 100-million-year-old Myanmar amber (Cretaceous), the latter representing the oldest record of these larvae. All specimens considered here possess a large, elongated terminal end. We performed an outline analysis of the shape of this terminal end for all so far known larval specimens sufficiently well preserved (in total 33 specimens: 17 extant, 14 Eocene, 2 Cretaceous). There is a recognisable difference between Eocene and extant specimens, yet it remains unclear whether this is due to different represented larval stages or an effect of evolution.

COPROLITES FROM CALVERT CLIFFS: MIOCENE FECAL PELLETS AND BURROWED CROCODILIAN DROPPINGS FROM THE CHESAPEAKE GROUP OF MARYLAND, U.S.A.

New finds of remarkable coprolites (fossilized feces) are here reported from the famous Miocene marine sediments of the Chesapeake Group exposed along Calvert Cliffs (Maryland, U.S.A.). Although vertebrate coprolites have been described from these deposits, here we provide the first description of tiny invertebrate fecal pellets. Thus far, these fecal pellets have only been found in the upper Miocene (Tortonian) St. Marys Formation. The micro-coprolites represent the coprulid ichnospecies Coprulus oblongus. The fecal pellets are found in small clusters or strings of dozens to masses of many hundreds. Pellets range in size from approximately 0.4 – 2.0 mm wide by 1.0 – 5.0 mm long, and range in color from gray to brownish black. Their length/diameter ratio is always very nearly 2. These coprulids have been found in a variety of Miocene fossils/concretions including a uranoscopid neurocranium, naticid gastropod, bivalve shells, barnacle tests, and in pellet-backfilled sinuous burrows through sediment. Because the fecal pellets are often found in tiny spaces or spaces thought to be inaccessible to shelled invertebrates, the coprulids are attributed to small and soft-bodied polychaetes or other annelids. Some coprolites attributed to crocodilians from the lower-middle Miocene Calvert Formation were tunneled into, presumably the result of coprophagy, by some unknown kind of organism(s). These compound trace fossils are in the form of burrows that excavate the coprolites, the sides of which are sculptured by scratch/gouge marks.

PERMIAN NON-MARINE BIVALVES FROM THE COLLIO AND GUNCINA FORMATIONS (SOUTHERN ALPS, ITALY): REVISED BIOSTRATIGRAPHY AND PALAEOBIOGEOGRAPHY

Non-marine bivalves are key fossils in Permian continental stratigraphy and palaeogeography. Although known since the end of 19th century, the occurrences from the continental basins of the Southern Alps have never been extensively studied. The non-marine bivalves from the Lower Permian Collio Formation (Brescian pre-Alps) are herein revised, and those from the Guncina Formation (Athesian District) are described for the first time. These two units yielded non-marine bivalves belonging to the genus Palaeomutela sensu lato, which is widespread in the Permian continental successions of eastern Euramerica. Three Palaeomutela morphotypes have been herein described: oval-subtriangular, subtrapezoidal and elongated. The latter includes several specimens herein assigned to Palaeomutela (Palaeanodonta) berrutii sp. nov. and dominates the Collio Formation association. The Guncina Formation yielded also the genus Redikorella, for the first time co-occurring on the same stratigraphic horizon of Palaeomutela, herein assigned to Palaeomutela (Palaeanodonta) guncinaensis sp. nov. To-date, it was generally accepted that the first members of the genera Palaeomutela and Redikorella occurred during the Ufimian (late Kungurian of the global scale) in the non-marine basins of the Cis-Ural Foredeep and of Angara, respectively. Such new finds in the early-middle Kungurian of southwestern Europe, well constrained by radioisotopic dating, suggest new global first appearance (First Appearance Datum) and a possible new center of origin of these genera. This fact raises new questions on biostratigraphy, palaeobiogeography and palaeoecology, which will require further research. If we assume that the genera Palaeomutela and Redikorella had only one center of origin, we need to hypothesise possible migration routes from SW Europe to the continental basins of Eastern Europe and Angara. Apparently, such migration could be better supported by a Pangaea B palaeogeographic configuration.

CHONDRITES-CLADICHNUS ICHNOCOENOSIS FROM THE DEEP-SEA DEPOSITS OF PIERFRANCESCO (CRETACEOUS; ITALY): OXYGEN- OR NUTRIENT-LIMITED?

The Italian Northern Apennines are acknowledged as the place where ichnology was born, but there is comparatively little work about their ichnological record. This study bridges this gap by describing two new ichnosites from the locality of Pierfrancesco, which preserve an abundant, low-disparity trace-fossil assemblage within the Late Cretaceous beds of the M. Cassio Flysch. Results show that lithofacies and ichnotaxa are rhythmically organized. The base of each cycle consists of Megagrapton-bearing calciclastic turbidites, which are overlain by marlstone beds with an abundant, low-disparity assemblage of trace fossils. This includes Chondrites intricatus, C. patulus, C. targionii, C. recurvus and Cladichnus fischeri. The cycle top consists of mudstones with no distinct burrows. The rhythmic pattern of Pierfrancesco reflects a deep-sea ecological succession, in which species and behaviour changed as turbidite-related disturbances altered the seafloor. This study opens the question of whether the Chondrites-Cladichnus ichnocoenosis represents low-oxygen or nutrient-poor settings.

THE PRESENCE OF AN ORBITOANTORBITAL FENESTRA: FURTHER EVIDENCE OF THE ANUROGNATHID PECULIARITY WITHIN THE PTEROSAURIA

The anurognathids are peculiar pterosaurs characterized by broad skulls with very short rostra and broadly arched jaws. The presence of distinct or confluent external naris and antorbital fenestra in these pterosaurs has been debated in the last years. The relatively well-preserved specimens of Batrachognathus volans show that the antorbital fenestra was confluent with the orbit forming an enormous orbitoantorbital fenestra. This feature is evident also in Jeholopterus ningchengensis. The consequent modification of the matrices of two recently published phylogenetic analyses about the in-group pterosaur relationships shows that the Anurognathidae are a derived clade of non-monofenestratan pterosaurs. Anurognathidae (including also 'Dimorphodon' weintraubi according to the definition by Hone 2020) are still a scarcely known clade because only a few specimens have been adequately described in the literature.