Forschen und Sammeln.

The Carnian Pluvial Episode (Late Triassic) was a time of global environmental changes and possibly substantial coeval volcanism. The extent of the biological turnover in marine and terrestrial ecosystems is not well understood. Here, we present a meta-analysis of fossil data that suggests a substantial reduction in generic and species richness and the disappearance of 33% of marine genera. This crisis triggered major radiations. In the sea, the rise of the first scleractinian reefs and rock-forming calcareous nannofossils points to substantial changes in ocean chemistry. On land, there were major diversifications and originations of conifers, insects, dinosaurs, crocodiles, lizards, turtles, and mammals. Although there is uncertainty on the precise age of some of the recorded biological changes, these observations indicate that the Carnian Pluvial Episode was linked to a major extinction event and might have been the trigger of the spectacular radiation of many key groups that dominate modern ecosystems.

The partial skeleton of a small tetrapod, collected from the lower Buchenstein Formation (uppermost Illyrian, Anisian Middle Triassic) of Piz da Peres (Northern Dolomites, Italy) is described. Incomplete ossification of some bones indicate that the specimen is a juvenile. Its absolute size and proportions, along with several skeletal structures show striking similarities with a juvenile specimen of Eusaurosphargis dalsassoi from the slightly younger Prosanto Formation (Switzerland), a taxon known also from the Anisian/Ladinian Besano Formation (Italy and Switzerland). The finding may suggest that during the middle-late Anisian the basins of the Northern Dolomites, of the Besano Formation and Prosanto Formation shared not only several taxa of fishes but also the emerged lands nearby had a similar reptilian fauna.

Information about distribution and habitat use of organisms is crucial for conservation. Bird distribution within the breeding season has been usually considered static, but this assumption has been questioned. Within-season movements may allow birds to track changes in habitat quality or to adjust site choice between subsequent breeding attempts. Such movements are especially likely in temperate mountains, given the substantial environmental heterogeneity and changes occurring during bird breeding season. We investigated the within-season movements of breeding songbirds in the European Alps in spring-summer 2018, using repeated point counts and dynamic occupancy models. For all the four species for which we obtained sufficient data, changes in occupancy during the season strongly indicated the occurrence of within-season movements. Species occupancy changed during the season according to fine-scale vegetation/land-cover types, while microclimate (mean temperature) affected initial occupancy in two species. The overall occupancy rate increased throughout the season, suggesting the settlement of new individuals coming from outside the area. A static distribution cannot be assumed during the breeding season for songbirds breeding in temperate mountains. This needs to be considered when planning monitoring and conservation of Alpine birds, as within-season movements may affect the proportion of population/distribution interested by monitoring or conservation programs.

Abstract

First finding of Ilybius wasastjernae (Sahlberg, 1824) in Italy (Coleoptera: Dytiscidae: Agabinae). It is here reported the first Italian record of Ilybius wasastjernae (Sahlberg, 1824), from a bog surrounded by a pine tree-spruce forest, in the province of Trento (north-eastern Italy). This is the southern-most record for this species in the Western Palearctic. At date, I. wasastjernae is known to occur in Italy only for this single, small and likely genetically isolated population. Illustrations of habitus, male genitals and habitat in which the species has been collected, are provided, together with brief considerations
on the status of this newly found species in Italy.

Vollständiger Titel der Publikation:

Triassic macro- and microfloras of the Eastern Southern Alps

Vollständige Autorenliste:

Evelyn Kustatscher, Hendrik Nowak, Giuseppa Forte, Guido Roghi & Johanna H.A. van Konijnenburg-van Cittert

Abstract (de):

In diesem Artikel geben wir einen Überblick über die historischen und neueren Makro- und Mikrofloren der Trias in den östlichen Südalpen. Neben den makrofossilen Sammlungen ermöglichen die palynologischen Daten vieler Fundorte die Rekonstruktion der Umweltbedingungen in den verschiedenen Stadien der Trias in den Südalpen. Darüber hinaus ermöglicht die (chrono-)stratigraphische Überarbeitung der verschiedenen Fundorte ein besseres Verständnis der geografischen und zeitlichen Verteilung der verschiedenen Taxa. Wir weisen das als Sphenozamites wengensis beschriebene Material der Gattung Macropterygium als Macropterygium wengensis (Wachtler et Van Konijnenburg-van Cittert, 2000) Kustatscher et Van Konijnenburg-van Cittert comb. nov. zu.

Abstract (en):

In this paper, we provide an overview of the historically known Triassic floras from the Eastern Southern Alps (e.g., Raibl and Recoaro), as well as the newer macro- and micro-plant assemblages that have been recorded during the 20th and 21st centuries. This includes some specimens stored in various European museums. The plant assemblages are presented here in chronostratigraphic order, starting with the Early Triassic, an interval of which only very few plant fragments are known from the area, whereas palynological data are available. In contrast to the Early Triassic, the Anisian floras (e.g., Kühwiesenkopf/Monte Prà della Vacca) are quite diverse, in both macrofloras – including in situ spores – and palynological assemblages. Similarly, the Ladinian of the Eastern Southern Alps is well known from the flora of Monte Agnello, which is outstanding in terms of both diversity and in total number of specimens, with additional information being derived from a large number of smaller macrofloral collections. The Carnian flora of the Eastern Southern Alps is also represented by a wide range of plant fossils, in contrast to the Norian/Rhaetian floras, which are represented only by a low number of macroremains and dispersed pollen and spores findings. A special subject of interest is the presence of amber in some of the Triassic sediments of the Southern Alps. Between the Wengen/La Valle and Heiligkreuz formations, the Dolomites represent the largest Triassic amber deposit known to date.

In addition to macrofossil collections, the palynological data from many localities permits the reconstruction of environmental conditions during the various stages of the Triassic in the Southern Alps. They provide evidence for at least three shifts from xerophytic to hygrophytic palynoassemblages. Moreover, (chrono-)stratigraphic revision of the various localities enables a better understanding of the geographic and temporal distribution of the various taxa.

Focusing on the overview picture of Triassic flora in the Eastern Southern Alps, only one necessary systematic aspect is highlighted herein. We transfer the material described as Sphenozamites wengensis to the genus Macropterygium as Macropterygium wengensis (Wachtler et Van Konijnenburg-van Cittert, 2000) Kustatscher et Van Konijnenburg-van Cittert comb. nov. The genus Macropterygium has been redefined for species with pinnate leaves with wedge-shaped segments that do not yield any cuticles and, thus, cannot be assigned to either the Cycadales or the Bennettitales, thereby distinguishing it from Apoldia and Sphenozamites.

Abstract (en):

The Laurinswand section in the Rosengarten/Catinaccio Massif (Dolomites, Southern Alps, Italy) covers the Permian–Triassic boundary in a proximal marine setting. The section has been studied for palynology, ostracods and carbonate microfacies. Five microfacies types are defined for the carbonates of the Bellerophon Formation (Changhsingian) in this section. Ostracod assemblages from the upper Bellerophon Formation show a moderate to high diversity and mostly indicate normal marine conditions, with some samples from the upper Casera Razzo Member being dominated by eurytopic forms. The ostracod fauna follows transgressive-regressive trends with low diverse assemblages occurring in the regressive parts. These trends are also reflected in the microfacies and can be assigned to three sequences. Palynological assemblages are dominated by phytoclasts, which is typical for proximal marine environments. Sporomorphs are represented predominantly by bisaccate and asaccate pollen grains and are mostly minor components of the palynofacies. Other minor, but consistent components in the Bellerophon Formation are acritarchs, Reduviasporonites and unidentified possible algae or fungi. The latter are particularly abundant in samples with ostracod faunas indicating restricted conditions. The Werfen Formation (uppermost Permian to Lower Triassic) yielded quantitatively poor palynological assemblages, with one sample from the Tesero Member showing a notable increase in spores and spore tetrads. This is indicative of the socalled “spore spike”, a well-known signal from this interval. One sample from the overlying Mazzin Member demonstrated a high relative abundance of Reduviasporonites, which may be related to mass occurrences of this taxon in the Tesero Member at Tesero and at other localities near the Permian–Triassic boundary. Such a mass occurrence normally pre-dates the spore spike, whereas at the Laurinswand, the former post-dates the latter considerably.