Bollettino SPI Vol. 55 (3)
Published in December 2016
Index
- Mananni I. (2016)
The role of micrites in the Sinemurian (Lower Jurassic) sponge-microbialite mounds from Foum Tillicht, central High Atlas, Morocco
pp. 157-169
doi:10.4435/BSPI.2016.14
Microbialites and sponges are the most significant components of the Sinemurian mounds of the Foum Tillicht Range in the central High Atlas of Morocco. Although these spectacularly well-exposed mounds have been reported in literature since the sixties, their genesis and their palaeoenvironmental settings are poorly understood. Recent studies have demonstrated that the characterization of the micritic component (allochthonous vs autochthonous micrite) and its distribution in the mound architecture represent a fundamental tool in reconstructing mound geometries and palaeoenvironmental evolution during their deposition. In this study, three main depositional intervals of the Lower/Upper Sinemurian mounds of the Foum Tillicht locality are recognized and a depositional model is suggested based on the characterization of their micritic component. The proposed depositional model includes a variation of the palaeoenvironmental conditions during deposition of the mounds. The allochthonous micrite and bioclast-dominated small mounds (ca. 1 m high and 0.5 m wide), observed within the lower depositional interval, suggest a marine palaeoenvironment with well oxygenated marine shallow water and high hydrodynamic conditions as well as, cyclically alternating suboxic/anoxic phases. These small mounds developed during short phases of relatively deeper water conditions. The mound evolution toward larger skeletal-rich (sponge) microbialite mounds indicates an evolution from a relatively fluctuating sea level to a more stable deeper water depositional environment, thus allowing time for the formation of a massive microbialite mound frame. The abundance of peloidal and aphanitic micrite associated with sponge tissue suggests an organic (microbial) origin through heterotrophic activities within a stressed suboxic environment. The decrease of the allochthonous micrite and the intermound deposit abundance involves a reduction of sedimentation rate and water energy. All these findings suggest that the sponge microbialite mounds were deposited within a stressed suboxic to anoxic setting characterized by calm and deep water conditions.
- Monaco P. (2016)
ulbichnus giornii n. ichnogen. and n. ichnosp.: a deep-water domichnion-praedichnion made by an eunicid polychaete (Marnoso-Arenacea Formation, Miocene, Northern Apennines, central Italy)
pp. 171-181
doi:10.4435/BSPI.2016.15
The ichnotaxon Bulbichnus giornii n. ichnogen. and n. ichnosp. is herein described. The trace fossil comes from the Marnoso-Arenacea Formation (Mount San Sepolcro, Northern Apennines, central Italy). It is a vertical, three dimensional structure that preserves the bulb imprint. The diagnostic characters of this crossichnion which is about 50 cm in length and > 4 cm in diameter, are an almost flat ventral side and a convex dorsal side. A rhythmic alternation of bulbs, each about 10 mm in diameter, disposed along the edges and on the dorsal side, is the most important additional feature. Bulbichnus giornii n. ichnogen. and n. ichnosp. could represent a new kind of domichnion- praedichnion ethologic behaviour of an eunicid worm comparable to modern Eunice aphroditois Pallas, 1788 (the bobbit worm), although a simple domichnion of an unknown crustacean cannot be excluded. This new ichnotaxon enriches the knowledge of the deep-sea ichnocenoses dominated by the Ophiomorpha group in foredeep sediments and is a new contribution for understanding deep-sea paleoethology.
- Jaselli L. (2016)
Description of the ophiuroid (Echinodermata) records in the Palaeontological Collection of the Museo di Storia Naturale “Antonio Stoppani” (Venegono Inferiore, Varese, Italy)
pp. 183-192
doi:10.4435/BSPI.2016.16
The Palaeontological Collection of the Museo di Storia Naturale “Antonio Stoppani” (Venegono Inferiore, Varese, Italy), consists of more than 4000 specimens that are housed in its store and partially on display to the public. The ophiuroid series is represented by a considerable number of specimens of extant and fossil ophiuroids. The aim of the present study is to provide a catalogue of these ophiuroids together with their taxonomic assignment and illustrations of their anatomical features.
- Zoboli D. & Pillola G.L. (2016)
Quaternary mammal fauna from “Surconis”, Bolotana (Sardinia, Italy)
pp. 193-203
doi:10.4435/BSPI.2016.17
A mammal assemblage discovered in a small fissure filling in the Surconis area, near the village of Bolotana (Marghine mountain range, central-western Sardinia, Italy) is described herein. The association is composed of several taxa: Prolagus sardus, Microtus (Tyrrhenicola) henseli, Rhagamys orthodon, Cynotherium cf. sardous and Praemegaceros (Nesoleipoceros) cazioti. The analysed assemblage infers a Late Pleistocene or Early Holocene age (“Microtus [Tyrrhenicola]” Faunal Complex). The Surconis assemblage represents to date the richest fossil mammal site reported in the Marghine mountain range.
- Sciuto F. (2016)
Ostracods associated with cold-water corals in the Pleistocene of Scoppo (Messina, Sicily) and description of two new species
pp. 205-217
doi:10.4435/BSPI.2016.18
Ostracod assemblages associated with deep-water corals from the Pleistocene (early Calabrian - MNN19b and 19c biozones) sedimentary succession cropping out along the Scoppo hill (Messina, Sicily) have been studied. Thirty-five taxa were recognized in the samples examined. The association mainly consisted of Pseudocythere caudata Sars, 1866, followed by Macrocyprina succinea (Müller, 1894), Bythocypris obtusata (Sars, 1866), B. bosquetiana (Brady, 1866), Paradoxostoma simile Müller, 1894 and Sclerochilus contortus (Norman, 1862) It has been attributed to a palaeoenvironment located within the deeper horizons of the Circalittoral Zone and higher horizons of the Bathyal Zone. The presence and abundance of shallow water phytal taxa of the genera Paradoxostoma, Paracytherois and Sclerochilus has been explained by the capability of these organisms to extend towards deep environments in the presence of food resources availability. In the Scoppo palaeoenvironment food was presumably provided by organic matter produced by deep coral colonies, as observed for comparable communities in North Atlantic, the Caribbean Sea and off Santa Maria di Leuca in the Mediterranean. Some particularly significant species are illustrated, and two species, i.e., Bythocythere agostinae n. sp. e Microxestoleberis scillae n. sp., are described.
- Spadini V. (2016)
First occurrence of the genus Bathelia (Anthozoa, Scleractinia) from the Mediterranean Pliocene
pp. 219-222
doi:10.4435/BSPI.2016.19
- Marra A.C., Carone G. & Bianucci G. (2016)
Sperm whale teeth from the late Miocene of Cessaniti (Southern Italy)
pp. 223-225
doi:10.4435/BSPI.2016.20
- Zoboli D., Pillola G.L. & Rook L. (2016)
New remains of Macaca majori Azzaroli, 1946 (Primates, Cercopithecidae) from Is Oreris (Fluminimaggiore, southwestern Sardinia)
pp. 227-230
doi:10.4435/BSPI.2016.21
- RASSEGNA DELL’ATTIVITÀ SOCIALE
Adunanza dell’Assemblea dei Soci della Società Paleontologica Italiana – Museo di Storia Naturale, via delle Medaglie d’Oro 51, Faenza (RA)- 27 Maggio 2016