Bollettino SPI Vol. 58 (2)
Published in September 2019
Index
- Rosso A. & Sciuto F. (2019)
First fossil record of Atlantisina (Bryozoa) from the Gelasian of Sicily:
a new piece of evidence to unravel past bryodiversity
of the deep Mediterranean Sea
pp. 141-154
doi:10.4435/BSPI.2019.01
Atlantisina mylaensis n. sp. is described from sediments deposited in deep-water settings during the Gelasian (early Pleistocene) that presently crop out at Capo Milazzo Peninsula (NE Sicily, Mediterranean Sea). The new species belongs to a genus recently erected for eight species that presently thrive on north-eastern Atlantic seamounts. Atlantisina mylaensis n. sp. is characterised by a prominent process located proximally to the orifice and consisting of two stout and slightly diverging lateral branches that end in bifurcate tips and are separated by a deep groove leading to a U-shaped morphology in proximo-frontal view. This species extends the stratigraphic distribution of the genus at least to the early Pleistocene, when its geographical distribution included the Mediterranean and, presumably, the Atlantic. This fossil record fits well within the frame of the observed segregation of an eastern group of Atlantisina collar-bearing species and the central Atlantic group of collar-missing species, although it does not explain how the genus diversified. The species adds to the numerous taxa already known from the same bryozoan association, confirming its Atlantic biogeographic affinity and the high bryodiversity of the Capo Milazzo associations in comparison to other known fossil and present-day deep-water faunas from the Mediterranean. However, further studies are needed in order to understand tempo and mode of the changes that affected the Mediterranean deep-water bryodiversity over time.
- Pignatti J., Mariotti N., D’Arpa C. & Sorbini C. (2019)
Mesosceptron Fucini, 1915 from the Sinemurian of Sicily: an aulacoceratid cephalopod and not an octocoral.
pp. 155-164
doi:10.4435/BSPI.2019.02
The genus Mesosceptron Fucini, 1915 from the Sinemurian of Montagna del Casale, Sicily, was originally described as a pennatulacean octocoral. The nominal genus is based on eight new species; no type species was fixed in the original publication. Re-examination of the type specimens of these species shows that they are incompletely preserved coleoid rostra that according to current systematic practice may belong to more than one genus within the xiphoteuthidid Aulacoceratida. In order to clarify the systematic attribution of the nominal genus Mesosceptron, we designate herein as its type species, M. neumayeri, and designate a lectotype for the latter; we also designate lectotypes for M. exagonum and M. magnum. Consequently to this nomenclatural act, the nominal genus Mesosceptron becomes a subjective junior synonym of Atractites Gümbel, 1861. We also include herein comments upon nomenclatural aspects of the co-occurring ammonite fauna.
- Manganelli G. & Spadini V. (2019)
Megascyliorhinus miocaenicus (Chondrichthyes, Galeomorphii)
from the Zanclean (early Pliocene) of San Quirico d’Orcia, central Italy
pp. 165-170
doi:10.4435/BSPI.2019.12
Two almost complete teeth, one anterior and one lateral, of the extinct shark Megascyliorhinus miocaenicus (Antunes & Jonet, 1970) are reported from the early Pliocene of San Quirico d’Orcia, Tuscany, central Italy. The teeth are similar in size and morphology (vertical striations of the crown base, indistinct cutting edge of the crown and accessory cusplets) to conspecific teeth described in literature. This is the first unequivocal report of a rare and enigmatic shark in the Pliocene of central Italy. A Pliocene tooth from Allerona, Umbria, central Italy, formerly assigned to Scyliorhinus sp., may also belong to Megascyliorhinus miocaenicus.
- Jukar A.M., Sun B., Nanda A.C. & Bernor R.L. (2019)
The first occurrence of Eurygnathohippus Van Hoepen, 1930
(Mammalia, Perissodactyla, Equidae) outside Africa
and its biogeographic significance
pp. 171-179
doi:10.4435/BSPI.2019.13
The Pliocene fossil record of hipparionine horses in the Indian Subcontinent is poorly known. Historically, only one species, “Hippotherium” antelopinum Falconer & Cautley, 1849, was described from the Upper Siwaliks. Here, we present the first evidence of Eurygnathohippus Van Hoepen, 1930, a lineage hitherto only known from Africa, in the Upper Siwaliks during the late Pliocene. Morphologically, the South Asian Eurygnathohippus is most similar to Eurygnathohippus hasumense (Eisenmann, 1983) from Afar, Ethiopia, a species with a similar temporal range. Eurygnathohippus appears to have dispersed into South Asia from the west via the Levantine Corridor and the Middle East in the early Pliocene. The presence of this lineage in the Indian Subcontinent refines our understanding of equid evolution and biogeography in the region.
- Corriga M.G. & Corradini C. (2019)
The conodont apparatus of Zieglerodina eladioi (Valenzuela-Ríos, 1994)
pp. 181-185
doi:10.4435/BSPI.2019.14
Zieglerodina eladioi (Valenzuela-Ríos) is a small ozarkodinid from the latest Přídolí (Silurian) and the Lochkovian (Lower Devonian), up to now documented only in areas of North Gondwana. Material from Morocco, the Carnic Alps, and Sardinia provide the basis for the seximembrate reconstruction of this conodont species’ apparatus (consisting of P1, P2, M, S0, S1, and S2 elements). The ramiform elements of Zieglerodina eladioi are characterised by an alternate denticulation with spike-like denticles, further confirming the attribution of the species to the genus Zieglerodina.
- Fornaciari B., Giusberti L. & Papazzoni C.A. (2019)
Alveolina postalensis n. sp. (Foraminiferida, Alveolinidae) from the
upper Ypresian of Monte Postale and Pesciara di Bolca (northern Italy)
pp. 187-199
doi:10.4435/BSPI.2019.15
A new species of the genus Alveolina, Alveolina postalensis n. sp., is herein described from the Monte Postale and Pesciara di Bolca sites (northern Italy). Our biometric data allow us to distinguish this species from the related Alveolina croatica Drobne, 1977, A. levantina Hottinger, 1960, and A. hottingeri Drobne, 1977. We hypothesise that Alveolina postalensis n. sp. could be the ancestor of A. croatica and that A. postalensis n. sp. and A. levantina could share a common ancestor. Based on the larger foraminiferal assemblage cooccurring with the new taxon, we can ascribe Alveolina postalensis n. sp. to the SB11 Zone (middle Cuisian, upper Ypresian, lower Eocene).
- Cacciari M., Amorosi A., Campo B., Marchesini M. & Rossi V. (2019)
Palynology of the late Quaternary succession of the Arno Plain (northern Italy):
new insights on palaeoenvironmental trends and climate dynamics
pp. 201-221
doi:10.4435/BSPI.2019.16
Palynological analyses, backed by meiofauna (ostracods and benthic foraminifers), sedimentological and radiocarbon data, enabled the identification of late Quaternary turnovers of depositional environments and coeval vegetation dynamics from a ca. 30 m-long core succession (core PA1), retrieved in the Arno delta area (N Italy), 2 km landwards of the innermost outcropping beach ridge. Based on the identification of 213 palynomorph taxa (pollen and spores), eleven ecological groups were elaborated and their relative frequencies stratigraphically plotted, allowing the identification of eight bio-sedimentary units (BSUs) and four vegetation phases dated to the late Pleistocene onwards. The former record palaeoenvironmental changes, mainly in terms of water-table level and salinity. The latter reflect different palaeoclimate conditions at both Milankovitch and sub-Milankovitch timescales, relying on the proportion of montane versus Mediterranean taxa. The vertically stacked pattern of BSUs reveals two transgressive-regressive cycles developed above an alluvial plain succession stratigraphically assigned to the penultimate glacial interval (Marine Isotope Stage-MIS 6). Both depositional cycles show a transgressive portion composed of swampy-lagoonal clays formed under interglacial conditions. Pollen (Mediterranean forest with increasing optimum-like conditions) suggests a MIS 5e age for the lowermost transgressive interval, whereas the palynological assemblage (Mediterranean/ sub-Mediterranean forest) and radiocarbon ages consistently indicate an early Holocene age (ca. 9800-7400 cal yrs BP) for the uppermost one. A climate-driven phase of subaerial exposure, likely related to the onset of the last glacial period, affected the MIS 5e lagoon, as testified by the record of an open/sparse pine forest within pedogenised alluvial deposits sandwiched between the two lagoon intervals. By contrast, the early Holocene lagoon experienced a long-term trend of sedimentary filling by river inputs under rather stable interglacial, highstand conditions. Only at the end of climate optimum conditions, marked by a peak of Fagus dated around 5000 cal yrs BP, the lagoon turned into a delta plain. This study documents the successfully use of a multi-proxy, palynological-based approach to investigate the complex interplay between environments, vegetation and climate changes in alluvial-coastal plain contexts and within a sequence-stratigraphic perspective.