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New Discoveries
Fossil Plants, dinosaurs
The Fossil Flora of the Wengen Formation (Ladinian)
in the Dolomites (Italy)
Michael Wachtler* & Johanna H.A.van Konijnenburg-van
Cittert**
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Fossil plants from the Wengen Formation (Ladinian, Upper Triassic) in
the Dolomites (Italy) have been known for over 100 years. The best
remains originate from the Zoldo Valley, from Corvo Alto near Cortina,
Prags, Ritberg near Wengen, Col Alto near Corvara and the Gröden Valley.
The floral composition is remarkably different from that of other
European contemporaneous floras such as in Austria, Germany and France.
The main floral components in the Wengen Formation are several Voltzia
species, including the new species Voltzia ladinica n. sp., Voltzia
pragsensis n. sp. and especially Voltzia dolomitica n. sp., followed by
the conifer Yuccites vogesiacus and the seedfern Ptilozamites heeri.
Equisetites arenaceus, the most common plant in the German Keuper flora,
is very rare in the Dolomites just as Pterophyllum jaegeri (a
Cycadophyte abundant in the Lunz flora in Austria and common in
Germany). Several fern species occur e.g. Anomopteris mougeotii (also
known from the Buntsandstein of France), Cladophlebis leuthardtii and
Neuropteridium grandifolium. Cycadophytes are further represented by
Bjuvia dolomitica n. sp., Taeniopteris sp. and Sphenozamites wengensis
n. sp. A single specimen of the conifer genus Elatocladus has been
recorded as well.
A new Late Anisian (Illyrian) vertebrate ichnosite from the Dolomites
(Val Duron, Val di Fassa)
Marco AVANZINI, Michael WACHTLER, Elio Dell’Antonio, Rossana TODESCO.
In the Southern Italian Alps, Lower and Middle Triassic tetrapod
footprints are known since the first decade of 1900 but extensive
research was lead only in the last 30 years with the discovery of
vertebrate tracks in many sites of the Dolomite region and surrounding
areas (Avanzini et al., 2001). The main ichnoassociations are preserved
in terrigenous and carbonate sediments Anisian in age, deposited in
continental, lagoonal and peritidal environments.
The new here reported ichnosite is located in the central Dolomites (Val
Duron, Val di Fassa) and occurs in the Morbiac dark Limestones Fm.
(Illyrian). It prevalently consists of silty, decimetre-thick grey or
light brown lime wackestones and packstones with foraminifers and
ostracods. Stromatolite bindstones and thin grey or green siltstones
layers are interbedded. Plant debris is common. The depositional
environment is referable to a marine marginal setting with lagoons and
swamps contamined by terrigenous imputs.
In the lower portion of the unit, two main layers are interested by
vertebrate trampling. In the lowermost layers Rhyncosauroides isp. is
largely represented, along with Rhynchosauroides tirolicus Abel 1926
footprints. The uppermost layer yields some archosaurs footprints with
different degree of preservation. The best preserved are Chirotherium
barthii Kaup 1835 and Brachychirotherium aff. parvum Hitchcock 1859 (sensu
Brandner,1973).
This association seems coherent with the Rhynchosauroides tirolicus -
Rotodactylus lucasi Faunal Unit proposed by Avanzini and Mietto (2005)
for the Early Illyrian.
MIDDLE TRIASSIC (ANISIAN) FERNS FROM KÜHWIESENKOPF (MONTE PRA´ DELLA
VACCA), DOLOMITES, NORTHERN ITALY
by JOHANNA H. A. VAN KONIJNENBURG-VAN CITTERT*, EVELYN KUSTATSCHER and
MICHAEL WACHTLER
This paper deals with the description of the ferns found in the
recently discovered Anisian locality of Kühwiesenkopf (Monte Pra` della
Vacca). A revision of the genera and species involved has been
undertaken where necessary. Because of transitional material found at
Kühwiesenkopf, the number of Neuropteridium species found in the
European Middle Triassic floras is reduced from five to three: N.
voltzii (Brongniart) Schimper, N. elegans (Brongniart) Schimper and N.
grandifolium (Schimper et Mougeot) Compter. The fertile material
attributed to this genus is transferred from the illegitimately
published genus Crematopteris Schimper and Mougeot to the genus
Scolopendrites Goeppert, in two species: S. scolopendrioides (Brongniart)
comb. nov. and S. grauvogelii sp. nov. Anomopteris mougeotii Brongniart
is unequivocally recorded for the first time from Italy. Gordonopteris
lorigae gen. et sp. nov. is described for tripinnate fern fronds without
the aphlebiae typical for the bipinnate genus Anomopteris but in which
both sterile and fertile pinnule resemble closely those from that genus.
Two probable marattialean ferns are described and recorded for the first
time from the Middle Triassic of Italy: Marattiopsis sp. and Marantoidea
sp. The nomenclature of the latter genus is discussed. Some ferns
attributed to morphogenera are also described, namely: Sphenopteris
schoenleiniana (Brongniart) Presl, Cladophlebis remota (Presl) comb. nov.
and Cladophlebis sp. Moreover, two specimens from Kühwiesenkopf are
described under gen. et sp. indet. as we are unsure if they are ferns or
seed ferns. Similar material has been described from the Scythian of
China as Neuropteridium curvinerve Wang and Wang.
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