First record of Pliensbachian (Lower Jurassic) amber and associated palynoflora from the Monti Lessini (northern Italy)

Megaspores from the Lower Jurassic (Pliensbachian) Rotzo Formation (Monti Lessini, northern Italy) and their palaeoenvironmental implications

“…This lack of lycophyte macrofossils could be related to the fragile nature of these plants inhibiting their preservation as fossils or it could be linked to unfavourable environmental conditions, meaning that these plants were rare elements of the flora (Batten 1974;Skog and Hill 1992;Kovach and Batten 1993;Wellman 2015, 2016). A recently discovered outcrop near Bellori village (Verona Province) yielded not only amber, bivalves, foraminifers, solitary corals, ostracods and carbonised wood (Neri et al 2016) but also several types of megaspores supporting the former theory.…”

“…The first outcrop is in a quarry near Bellori village in the Grezzana municipality (Verona Province; N 45°35′ 48.6″, E 10°59′ 48.0″). The exposure, which is about 25 m thick, yielded the first Lower Jurassic amber of Italy (Neri et al 2016). The strata are composed of grey-bluish limestone (yellow when weathered; 0.1-1 m thick), well stratified, alternating with dark clayey/marly layers (3-4 cm thick) rich in organic matter including coal layers (Fig.…”

“…The lower part of the Rotzo Formation yielded also a rich palynoflora including Ischyosporites variegatus (Couper) Schulz, 1967, Leptolepidites major Couper, 1953, Matonisporites crassiangulatus Levet-Carette, 1964, and Trilites lygodioides Mai, 1967, that was previously attributed to the Toarcian (Schulz 1967), but is now known to extend to the Sinemurian-Pliensbachian (Avanzini et al 2006). Recently, Neri et al (2016) described the first amber from this formation. The Rotzo Formation has been dated, based on foraminifera, ammonites, green algae and isotopic analyses ( 13 C and 87 Sr/ 86 Sr), to the Pliensbachian (Avanzini et al 2006;Fugagnoli 2004;Posenato and Masetti 2012;Franceschi et al 2014).…”

“…During the Jurassic, northeastern Italy was characterised by the Trento Platform, a palaeo-high confined by the Belluno Basin to the east and Lombardy Basin to the west Winterer and Bosellini 1981;Masetti et al 1998;Neri et al 2016). The Trento Platform corresponds today to an area that extends from Verona to the Dolomites (northsouth direction) and from Monte Grappa to Lake Garda (eastwest direction) .…”

“…Uvaesporites) are well represented in the palynological record from the Rotzo Formation (van Erve 1977; Avanzini et al 2006;Neri et al 2016). This lack of lycophyte macrofossils could be related to the fragile nature of these plants inhibiting their preservation as fossils or it could be linked to unfavourable environmental conditions, meaning that these plants were rare elements of the flora (Batten 1974;Skog and Hill 1992;Kovach and Batten 1993;Wellman 2015, 2016).…”