Bollettino SPI Vol. 39 - Issues 1, 2, 3
Issue 1
Published in February 2000
- Gnoli M., Histon K. & Serventi P. (2000)
Revision of Silurian cephalopods from the Carnic Alps: The Gortani and Vinassa de Regny collection, 1909
pp. 3-12
The type specimens of Gortani & Vinassa de Regny described and partially figured in 1909 have been revised according to an up to date taxonomy. A synthetic systematic table of the whole collection is also given. The aim is to clarify the paleobiogeographical distribution of the described species within the North Gondwana area during the Silurian.
- Senowbari-Daryan B. & Bernecker M. (2000)
Crustacean microcoprolites from the Upper Triassic, Oman
pp. 13-20
The crustacean microcoprolite association of Favreina omanensis n. sp. and Thoronetia quinaria Brönnimann, Caron &
Zaninetti occurs in shallow marine carbonates of the Upper Triasssic Misfah Formation (Jabal Kawr), Oman. This is the first occurrence of
microcoprolites reported in Triassic deposits of Oman.
- Chiocchini M. & Mancinelli A. (2000)
Marzoella ficcarellii n. gen., n. sp. (Foraminiferida) nel Dogger del Lazio nord-orientale (Italia)
pp. 21-28
A new foraminifer Marzoella ficcarellii n. gen., n. sp. from the Bajocian of the North-Eastern Latium (central ltaly) is described. lt occurs in the lower part of the Colle Marzo stratigraphic section, which crops out along the north-eastern slope of M. Giano.
The new foraminifer is characterized by a plurilocular, trochospiral test with spiral side evolute and more convex than the involute umbilical side, periphery rounded, peripheral outline slightly lobated. Spherical proloculus followed by 2.5-3 trochospiral whorls, 10-12 chambers in the last whorl, slightly curved septa, sutures on the umbilical side slightly depressed, radial; broad umbilicus filled by an umbilical plug composed of calcareous-hyaline material which extends and partially covers the umbilical portion of the septa. Aperture single, probably archued, at the base of the septum, which can be complicated by a folding of the septum (retrosifonate?). Wall calcareous, imperforate, microgranular. The carbonatic dolomitic sediments which contain Marzoella ficcarellii n. gen., n. sp. were deposited at the edge of the Apennine carbonate platform, characterized by a rather strong water energy.
- Landra G., Cecca F. & Vasicek Z. (2000)
Early Aptian ammonites from the top of the Maiolica and the anoxic “Selli level” (Lombardy, Southern Alps)
pp. 29-45
The paper deals with the description of Early Cretaceous ammonite faunas from black shale layers intercalated within the transition between the Maiolica limestones and the marls of the Marne di Bruntino Formation in a quarry near Cesana Brianza (Como province, Northern Italy). For the first time in Italy ammonites have been collected also in the regional equivalent of the “Livello Selli’; corresponding to the oceanic anoxic event OAE 1a. The ammonites studied have been assigned to the Early Aptian by means of integrated bio-and magnetostratigraphy. In fact, ammonite biostratigraphic markers are scarce in a distal Mediterranean area such as the Lombardy basin because of the evolutionary stasis in the majority of the groups and the rarity of representatives of the family Deshayesitidae; the latter are absent at Cesana Brianza. From a palaeoecological point of view, most of the studied ammonites had apparently a pelagic mode of lift and some of them were opportunists (Leptoceratoidinae). In the ‘Livello Selli” anoxia probably did not reach the upper part of the water column.
- Forteleoni G. & Eliášová H. (2000)
I rapporti tra il bivalve Lithophaga alpina (Zittel, 1866) ed il corallo Actinastrea elongata Alloiteau, 1954, nel Cretaceo superiore dell’Italia nord-orientale
pp. 47-54
The close association between Lithophaga alpina and Actinastrea elongata from the Santonian (Fadalto Limestone formation) of north-eastern ltaly indicates the highly specialized mode of life of the bivalve, which inhabited only living corals. The symbiotic relationship between Lithophaga alpina and colonial corals was not strictly unispecific as in the Santonian of the Gosau Formation the same bivalve species was found also inside Actinastrea decaphylla (Michelin, 1847).
- Manganelli G. & Giusti F. (2000)
The gastrocoptids of the Fossil Forest of Dunarobba ( Central Italy) and a preliminary revision of the European Tertiary nominal species of Albinula and Vertigopsis (Gastropoda Pulmonata: Gastrocoptidae)
pp. 55-82
The clay encrusting the trunks of the Middle-Late Pliocene “Fossil Forest of Dunarobba” (Avigliano Umbro, Perugia, Italy; sheet 130 of the geological Map of Italy) contains a rich snail fauna consisting of about twenty species, some of which are of great palaeontological and biogeographical interest. Two of these species belong to the Gastrocoptidae, a family of pupillid snails (Gastropoda, Pulmonata) never previously found in Apennine Italy: Gastrocopta (Albinula) acuminata (Klein, 1846) sensu Gottschick & Wenz (1916) and G. (Vertigopsis) moravica (Petrbok, 1959).
In order to provide a well based classification of the Dunarobba Gastrocopta, we reexamined the nominal taxa of the species-group of Albinula and Vertigopsis described from the Palaearctic. The difficulty of tracing type material of the eastern European and Asian taxa, however limited the survey to taxa from central western Europe. Current species-level taxonomy of the fossil Palaearctic Albinula is mainly derived from Wenz’s (1923) survey in the Fossilium Catalogus, but our revision suggests quite a different scenario from that proposed by Wenz. The following nominal taxa are discussed and when possible revised: Pupa acuminata Klein, 1846, Vertigo turgida Reuss, 1849, Pupa lartetii Dupuy, 1850, Vertigo quadriplicata Braun, 1851, Pupa quadridentata Klein, 1853, Pupa dupuyi Michaud, 1855, Pupa lamellidens Sandberger, 1858, Leucochilus quadriplicacum mut. suevica Boettger, 1889, Vertigo fossanense Sacco, 1885, Vertigo fossanensis var. quatuordentata Sacco, 1886, Leucochylus edlaueri Wenz, 1921, Gastrocopta acuminata wenziana Pilsbry, 1921, Gascrocopta (Albinula) rhenana Geissert, 1983. Unfortunately, we were unable to clarify the identity of the two oldest established nominal species, Pupa acuminaca and Vertigo turgida. The identity of the former was therefore accepted in the sense of Gottschick & Wenz (1916) and the other is still uncertain. The study of new topotypical material and designation of neotypes is the only way to clarify the identity of these two species. This is a necessary preliminary or a clear definition of these species and for an approach to the phylogenetic and biogeographical history of the group.
Comparison of typical or topotypical material of all European fossil nominal taxa of Vertigopsis –Gastrocopta (Vertigopsis) dehmi Schlickum & Strauch, 1979, Gastrocopta (Vertigopsis) magna Steklov, 1966, Gastrocopta (Vertigopsis) meijeri Schlickum, 1978, Vertigo (Vertigo) moravica Petrbok, 1959, Gastrocopta (Vertigopsis) moravica oligodonta Krolopp, 1977, except Gastrocopta (Vertigopsis) nikitini Krasnenkov, 1979, and Gastrocopta (Vertigopsis) nikitini urivica Krasnenkov, 1979, demonstrates that no substantial, dimensional or nondimensional character distinguishes V. moravica, G. meijeri, and G. dehmi from each other and from the Dunarobba specimens. Only G. moravica oligodonta, G. nikitini nikitini and G. nikitini urivica differ slightly by the absence of the infrapalatal denticle (that between the upper and the lower palatal teeth). This feature does not seem substantial enough to assign them to a distinct specific taxon. The inclusion of G. magna in Vertigopsis is problematical. G. magna is distinguished from all modern Nearctic and fossil western Palaearctic Vertigopsis species by a bifid composite anguloparietal lamella and a sort of low transverse lamina in basal – infrapalatal position.
As far as the biogeography and relationships of Vertigopsis are concerned four scenarios seem possible.
- Aiello G., Barra D. & Bonaduce G. (2000)
Systematics and biostratigraphy of the ostracoda of the Plio-Pleistocene Monte S. Nicola section (Gela, Sicily)
pp. 83-112
The ostracod assemblages of the Plio-Pleistocene section of Monte S. Nicola (Gela, Sicily) are studied. The section, sampled at 2 m intervals, yielded 113 species, belonging to 46 genera, ten of which are left in open nomenclature due to scarce or badly preserved material. The following species: Bairdoppilata profunda sp. nov., Occultocythereis culter sp. nov. and Propontocypris dromas sp. nov. are described as new. Most of the species are treated taxonomically, with data on their stratigraphical distribution and palaeoecology. Some species which were imperfectly described are better illustrated. The qualitative distribution of the species through the section, shows a high number of appearances and disappearances. First appearances of species are staggered throughout the section; this and the limited stratigraphical ranges of certain species indicate the biostratigraphical potential of the Ostracoda. In particular, the genus Krithe is of high diversity and numerous species appear restricted to well defined and frequently short intervals. Many of the Krithe species have never been recorded from the Atlantic, suggesting the possibility that the Mediterranean Basin, due to its peculiar character, may have acted as a laboratory of evolution especially of this genus.
Issue 2
Published in June 2000
- Holland C.H. (2000)
Harrisoceras and Temperoceras closely related cephalopod genera from the British Silurian
pp. 117-122
The rare British Silurian cephalopod Harrisoceras distans (J. de C. Sowerby, 1839) and the common species Temperoceras ludense (J. de C. Sowerby, 1839) are described and generically assigned. Together with Columenoceras Barskov 1960, of which the species C. grande occurs in Sardinia, the genera form a compact group within the Family Geisonoceratidae.
- Barattolo F. & Parente M. (2000)
New observations on Uragiella liasica (Lebouché & Lemoine) (Green Algae, Dasycladales) from the type-locality (Canders, Languedoc -Southern France)
pp. 123-137
New observations on abundant material ftom the type-locality of Uragiella liasica Lebouché & Lemoine reveal the presence of tufts of secondary laterals and suggest a new interpretation of the morphology of the ”primary pores “. The large and irregular pores, previously interpreted as Uragiella-type primary pores, are believed to result from incomplete calcification of primary laterals bearing a fertile ampulla originating in proximal-lateral position and lying very close above the lateral. Based on these new observations and interpretation the new combination Cylindroporella ? liasica is proposed.
- Maiorano P. (2000)
lntegrated calcareous nannofossil and foraminiferal biostratigraphy of Pliocene terrigenous deposits from the Southern Apennines (Lucania, ltaly)
pp. 139-155
Pliocene terrigenous sedimems cropping 0ut at the transition between the Southern Apennines thrust belt and the Bradanic Foredeep (S0uthern ltaly) were investigated by means of an integrated biostratigraphic study on calcareous nannofossil and planktonic foraminiferal assemblages. The examined deposits have been previously referred to the transgressive part of the Bradanic Cycle, late Pliocene to early Pleistocene in age.
Despite the presence of a considerable amount of pre-Pliocene and Pliocene reworked specimens, and the rarity or the absence of some marker species, the quantitative approach to calcareous nannofossil biostratigraphy as well as the integration with foraminiferal data allow to recognize several biozonal events within the early Pliocene and the late middle to late Pliocene record. The first occurrences of Bulimina basispinosa and Bulimina marginata among the benthic foraminifera were also detected; these events permit to recognize the intervals VII and VIII of Spaak (1983), respectively. Two horizons characterized by abundant diatoms and silicoflagellates, well correlatable in two sections, have been observed. The biostratigraphic results allow to assert that in the studied area the conglomeratic-sandy and silty-clayey deposits are referable to the nannofossil Zone MNN14-15 and to the Globorotalia puncticulata planktonic foraminiferal Zone of early Pliocene age; the expanded clayey succession, that overlies the middle Pliocene conglomeratic and calcarenitic-sandy deposits, is middle to late Pliocene in age and spans the interval from the upper part of the nannofossil Zone MNN16a to Zone MNN19a – the Globorotalia crassaformis (partim) and Globorotalia inflata planktonic foraminiferal Zones. It is worth mentioning that the interval spanning the upper lower Pliocene to the lower middle Pliocene is not represented in the studied area. The biostratigraphic results, compared to previous stratigraphic data, suggest that the studied deposits are correlatable with two different sedimentary cycles, recognized in other areas at the outer border of dee Southern Apennines.
- Bonaduce G., Barra D. & Aiello G. (2000)
The Ostracods of the Plio-Pleistocene Monte San Nicola section (Gela, Sicily): an attempt of palaeoecological interpretation
pp. 157-164
The ostracod assemblages of the Plio-Pleistocene section of Monte S. Nicola (Gela, Sicily) are studied quantitatively.
The fluctuations in both the diversity and number of specimens are correlated with a climatic fluctuations as identified by Channell et al. (1992) using planktonic foraminifers.
The common occurrence of Agrenocythere pliocenica up to the second half of MPl5 and its spasmodic and rare occurrence at the base of MPl6, demonstrate the gradual disappearance of the psychrosphere in the area and the beginning of the thermospheric environment. In our opinion, the evident species turnover in the same interval supports the hypothesis of a change in Mediterranean circulation from estuarine to antiestuarine.
- Davoli F. (2000)
Mitriform Gastropoda from Tortonian (Upper Miocene) of Montegibbio hill (Northern Apennines, Italy)
pp. 165-215
Thirty-eight taxa of mitriform gastropods recovered from the classic Tortonian (Late Miocene) outcrop of Montegibbio (Northern Subapennines) are described and illustrated. Over 1300 specimens of mitre shells belonging to the historical collections of Doderlein, Coppi and Pantanelli as well as collected by the author, have been examined in order to overcome the excessive splitting existing inside the group and to simplify its present taxonomic ”status”. Eleven species of Mitra (subfamily Mitrinae) and eleven species of Cancilla (subfamily Imbricariinae) belong to the family Mitridae, whereas 11 species of Vexillum and 2 species of Thala represent the family Costellariidae. Three species of the genus Mitrolumna ( = Diptychomitra Bellardi), previously assigned to “Mitridae” are here attributed to the family Turridae. A cluster analysis approach has also been attempted to test our taxonomic proposal. The results are however quite disappointing and do not justify the great amount of requested calculations. Information on the geographic distribution and bathymetric range of recent Mitridae as well as the few available data on their ecology are supplied. Recent Mitridae live in warm and temperate sea-water rangingftom 42°N to 42°S latitude, inhabiting tropical seas mainly of the Indo Pacific region (87 species all belonging to the subfamily Mitrinae). Most of the species colonize soft or rocky bottoms of the intertidal zone and only a few live beyond the littoral zone at depths not exceeding 1,500 metres. The Mitridae assemblage of Montegibbio strongly confirms either the Tortonian age of the outcrop or the warm water “inner tropical” character of the basin. Indications on salinity are not so clear. Many species of Mitra recovered at Montegibbio were apparently able to live in high salinity water (over 38‰ like in the present Red Sea or Persian Gulf). They co-occur with species of Vexillum which may tolerate a salinity concentration lower than the average (like in Northern Adriatic Sea). These mixing can be explained by a resedimentation of near-shore and circalittoral faunas in a slope environment as already evidenced also far Cancellariidae.
- Ciangherotti A. & Esu D. (2000)
Paleoecologic and biochronologic meaning of the Early Pleistocene molluscan fauna from the Anghiari basin (Tiber River Upper Valley, Centrai Italy)
pp. 217-224
The Anghiari Basin, part of the Tiber River Upper Valley, is located on the Umbria-Tuscany boundary (Central Italy). A Lower Pleistocene sedimentary succession cropping out in a clay quarry in the locality Fighille/Citerna (Arezzo, Tuscany) has yielded rich non marine molluscan assemblages. They indicate that in the Early Pleistocene this area evolved from a mesophilous woody to a more open and damp environment through alternating palustrine phases (due to flooding episodes) and drier periods. The high species diversity and the occurrence of some species having a high climatic significance are indicative of a temperate-warm climate. The examined assemblages are characterized by the prevalence of still living terrestrial taxa; only three species are extinct: Gastrocopta (Vertigopsis) dehmi Schlickum & Strauch, Multidentula helenae Esu and Parmacella (Parmacella) cf. P. (P.) sp. l sensu Manganelli & Giusti. The structure of the molluscan assemblages is typical of an Early Pleistocene molluscan fauna that can be referred to the Tasso Faunal Unit.
- Dalla Vecchia F.M. (2000)
A new petalodont tooth (Chondrichthyes, Petalodontiformes) from the Lower Permian of the Carnic Alps (Friuli, NE Italy)
pp. 225-228
An isolated tooth of a petalodont chondrichthyan from the Lower Permian of the Carnic Alps (NE Italy) is here described. It resembles Petalorhynchus Newberry & Worthen, but differs in important features from teeth attributed to this genus (e.g., absence of a band of “imbricated ridges” on the base of the labial side of the crown) and probably corresponds to a new taxon. The specimen represents a petalodont previously unknown in the Permian since it does not belong to the Permian taxa. This report increases the petalodont diversity in the Alps, represented only by four specimens of the Late Carboniferous Petalodus ohioensis.
- Dalla Vecchia F.M. (2000)
A wing phalanx of a large basal pterosaur (Diapsida, Pterosauria) from the Norian (Late Triassic) of NE ltaly
pp. 229-234
Wing phalanx 4 of a large basal pterosaur is reported from the Dolomia di Forni Formation (middle Norian) of Friuli (northeastern ltaly). With a length of at least 137 mm, it is the longest wing phalanx 4 of a non-pterodactyloid pterosaur described up to now. This find from the Dolomia di Forni and others from Lombardy show that very large “rhamphorhynchoid” pterosaurs were present in the earliest pterosaurian fossil record. This suggests that basal pterosaurs reached the large size early in their evolutionary history, at least by Norian times.
- Girone A. (2000)
The use of fish otoliths for paleobathymetric evaluation of the Lower to Middle Pleistocene deposits in Southern ltaly
pp. 235-242
A continuous lower and middle Pleistocene succession consisting of clayey-silts and silty-clays, over 400 metres thick, crops out in the southwestern part of the Bradano Trough (Montalbano Jonico area). The bulk samples collected along this section contain otoliths referable to 51 teleost taxa. Eight otolith associations have been recognised and allowed to infer the paleobathymetric changes into the basin. The two associations from the basal part of the succession clearly indicate an upper slope environment (300-500 metres deep). On the other hand, the associations from the middle and the upper parts of the succession indicate some depth variations ranging between the shallow outer shelf and the transitional zone to slope.
- Marcolini F., Bonadonna F.P., Kotsakis T., Mazza P. & Zanchetta G. (2000)
Preliminary data on the micro- and macromammal remains from Casa Sgherri, Lower Valdarno (Tuscany, Italy)
pp. 243-252
Preliminary data on a new mammal bearing deposit of Lower Valdarno (on the right-hand side of the Arno River) are presented here. Macromammals include: Macaca sylvana florentina, Enhydrictis ardea, Acinonyx pardinensis, Sus strozzii, Pseudodama sp., Capreolus sp., and Leptobos sp. The micromammals are represented by: Glis sp., Mimomys pitymyoides, Mimomys cf M. pusillus, Mimomys sp. 1, Mimomys sp. 2, Apodemus dominans, Hystrix refossa, and Oryctolagus cf. O. lacosti. The assemblage is referable to the Middle or early Late Villafranchian and is therefore attributed to the Costa S. Giacomo or Olivola Faunal Units. This attribution confirms the most recent interpretations of the basin between Monti Pisani and Monte Albano, considering the basal portion of the fluvial deposits of the Massarella Unit as Late Pliocene.
Issue 3
Published in December 2000
- Perejón A., Fröhler M., Bechstädt T., Moreno-Eiris E. & Boni M. (2000)
Archaeocyathan assemblages from the Gonnesa Group, Lower Cambrian (Sardinia, Italy) and their sedimentologic context
pp. 257-291
Within the Cambrian Santa Barbara and Planu Sartu Formations (Gonnesa Group) of southwestern Sardinia several archaeocyaths bearing levels occur. The Santa Barbara Formation represents an isolated carbonate platform. It overlays a carbonate-elastic ramp (Punta Manna Formation, Nebida Group) as a result of a distinct episode of tensional tectonics. This caused a backstepping of the shallow water sedimentation area and the initiation of basinal successions (Planu Sartu Formation) in areas marginal to the platform. The archaeocyaths occur partly in place in microbial- archaeocyathan mounds, growing at the platform edge of western Iglesiente, but mainly reworked in breccia clasts or in turbiditic intervals. The following new archaeocyathan species are described from the Santa Barbara Formation: Nochoroicyathus oblongus n.sp., Fallocyathus? canalgrandensis n.sp., Erismacoscinus bornemanni n.sp., Antoniocoscinus sardicus n.sp. Three archaeocyathan assemblages have been identified, two of these occurring in the Santa Barbara and Planu Sartu Formations, and one at the top of the overlying San Giovanni Formation. In the former two the typical genera of the underlying Nebida Group, such as Tubicoscinus and Anthomorpha are lacking. This restricts the occurrence of archaeocyaths in the Nebida Group to the Botomian 1 and 2. Five genera are common to all of these levels: Nochoroicyathus, Rasetticyathus, Erismacoscinus, Coscinocyathus and Protopharetra. In the Santa Barbara and Planu Sartu Formations, the older assemblage (assemblage 1) is characterized by the genera Carpicyathus?, Sajanocyathus?, Fallocyathus? and Neoloculicyathus. For assemblage 2, the presence of Ajacicyathida gen. et sp. indet., Leptosocyathidae gen. et sp. indet., Rotundocyathus, Capsulocyathus and Tumulocyathus? is characteristic. We assign the time interval in which the above mentioned assemblages 1 and 2 occurred to the Botomian 3. At the top of the San Giovanni Formation (upper part of the Gonnesa Group) a third assemblage occurs, constituted by the genera Angaricyathus?, Pycnoidocyathus and Archaeocyathus. This third assemblage was assigned to the Toyonian 2-3.
- Pittau P. & Del Rio M. (2000)
Wenlock Chitinozoans of SE Sardinia (Italy)
pp. 293-309
The Silurian sequence of south-eastern Sardinia is exposed throughout the Gerrei and Sarrabus region, included in the homonymous tectonic units of the Outer Nappe Zone of the Hercynian Sardinian Chain. From the Llandovery, vesiculosus graptolite biozone, up to the Prìdolì, Scyphocrinites layers, and crossing the Silurian -Devonian boundary, the sequence consists of the “Lower Graptolitic Shales” unit with graptolitic lydites and alum-shales (Llandovery to lower Ludlow); the “Ockerkalk” (up to near the top of the Prìdolì), and the “Upper Graptolitic Shales” unit crossing the Prìdolì-Lochkovian boundary (M. uniformis, M. praehercynicus and M. hercynicus Biozones). In the Goni section, an investigation on chitinozoans has been conducted from the flexilis/belophorus to colonus/nilssoni graptolite biozones (upper Sheinwoodian to basal Ludlow). Of the nine graptolite biozones investigated, three yielded chitinozoans in full relief, three were barren, three only contained graphitized tests. A low specific diversity characterizes the Goni associations, among which three informal assemblages have been recognized on the basis of the appearance of new species and of the relative frequency of certain taxa. Among the taxa found the presence of Conochitina subcyatha, biozonal marker of Baltoscandia and Avalonia for the same stratigraphical interval is worthy of note. Five new species, Conochitina goniensis, Sphaerochitina ichnussae, Sphaerochitina jaegeri, Sphaerochitina serpaglii, ?Eisenackitina ampulla, characterizing the Goni assemblages, have been described.
- Paalits I. & Heuse T. (2000)
Taxonomic review of the acritarch genera Acanthodiacrodium Timofeev, 1958 and Diornatosphaera Downie, 1958
pp. 311-317
Following a previous suggestion, the acritarch genus Acanthodiacrodium Timofaev, 1958 is restricted to its type species A. dentiferum Timofaev, 1958; also, an emendation of the genus Diornatosphaera Downie, 1958 is proposed. About 152 species of Acanthodiacrodium are validly published; four of them are formally transferred herein to Diornatosphaera; viz., D. angusta (Downie, 1958), the type species; D. comptula (Rasul, 1979); D. echinata (Timofeev, 1959) and D. golubii (Fensome et al., 1990).
- Macchioni F. & Venturi F. (2000)
Leukadiellinae, n. subfam. of the Lower and Middle Toarcian. Origin and evolution of the genera Renziceras Arkell (1957) and Leukadiella Renz (1913)
pp. 319-339
During the biostratigraphic sampling in the Rosso Ammonitico Umbro-Marchigiano (Toarcian) in the locality of Migiana di M. Malbe (Corciano, PG), a specimen of the genus Leukadiella Renz was found with ventro-lateral spines. This find provided the stimulus to reconsider unpublished data from other locations currently under study, and to re-examine the systematic position of the genus Leukadiella and, for the first time, of the genus Renziceras Arkell. This has been possible in the latter case thanks to the opportunity to examine a fair number of specimens, given that almost 90 years after the species was erected (H. nausikaae, Renz, 1913), no other find of a specimen of the same had been published. The approach to the investigation took into consideration both the general morphology of the shells and their palaeogeographic and biostratigraphic distribution. The remarkable morphological similarity between Leukadiella and Renziceras proves that the former developed from the latter by neoteny instead of deriving from Bouleiceras Thevenin, as has until now been suggested by many authors. For this reason we believe that the institution of the subfamily Leukadiellinae n. subfam. should be considered, in order to set the former two genera in a more appropriate taxonomic entity, separating them distinctly from the subfamily Bouleiceratinae. We also take the opportunity to illustrate two specimens of Nejdia Arkell, a genus found for the first time in the Umbria-Marche Apennines, which were discovered in the S. Anna Quarry (Passo del Furlo, PS). Both forms are described both because of the novelty of their discovery and for comparison with the Leukadiellinae.
- Mancin N., Pirini C. & Lanfranchini P.L. (2000)
New species of Pararotalia Le Calvez, in Pliocene sediments of the Lower Valsesia and Western Liguria
pp. 341-350
The aim of this note is to describe Pararotalia padana n. sp., found in Pliocene outcrops of the Lower Valsesia and Western Liguria. The new species differs from the previously known Pararotalia species, such as P. armata (d’Orbigny, 1826) by possessing different size, number and shape of chambers and ornamentation.
- Manganelli G. & Giusti F. (2000)
Drepanostoma helenae, a new helicodontine land snail from the Lower Pliocene of Balze di Caspreno near Siena (central Italy) and a discussion on the status of Protodrepanostoma Germain, 1929 (Gastropoda, Pulmonata: Hygromiidae)
pp. 351-358
Drepanostoma helenae n. sp. is described from the non-marine Lower Pliocene of Balze di Caspreno (Siena, Italy). Analysis of the relationships of the new species has involved revision of the genus Protodrepanostoma Germain, 1929, and some species assigned to it. This suggested that Protodrepanostoma is a junior synonym of Drepanostoma Porro, 1838, and that some of the species recently assigned to Protodrepanostoma can be assigned to Drepanostoma. More research is required to allocate the other species, which are tentatively assigned to Helicodonta Férussac, 1821. D. helenae is the first species of the genus reported from the Neogene of Apennine Italy.
- Basso D. & Spezzaferri S. (2000)
The distribution of living (stained) benthic foraminifera in Iskenderun Bay (Eastern Turkey): a statistical approach
pp. 359-379
During a cruise carried out in Iskenderun Bay in June 1993, bottom sediments of 137 stations were grab-sampled in order to recover the living benthic foraminiferal fauna. Environmental parameters such as water depth, bottom temperature, salinity, density, pH and dissolved oxygen were also measured in situ. Calcium carbonate, organic matter content and sediment grain size were measured in the laboratory. Living benthic foraminifers were identified and counted. A statistical approach was used to relate abundance and distribution of benthic species and assemblages with the measured environmental parameters. The statistical treatment allowed the separation of three clusters A, B and C and 3 subclusters of B representing different discrete environments in Iskenderun Bay. Cluster A is characterized by species typical of high energy environments, well-illuminated shallow water, sandy-gravelly substratum and presence of sea grasses. Cluster B is separated by higher abundance of fine sediment. Subcluster B1 is characterized by species tolerant of high organic matter content and low oxygen. Subcluster B2 is characterized by species preferring muddy substrata, high nutrients and organic matter content. Subcluster B3 groups sandy-pelite-loving species living in waters not deeper than 50-100 m. Cluster C is characterized by species which may tolerate low salinity. Finally, our study reveals that the major controlling factor of the distribution of the assemblages in Iskenderun Bay appears to be the substratum. A minor role is played by the other environmental parameters such as organic matter, dissolved oxygen and, locally, the fresh-water input. The water depth is simply the gradient along which some environmental parameters, such as temperature, vary and is not a controlling factor itself.
- Mazzini M., Borselli V., Cioppi E. & Napoleone G. (2000)
Poggiorosso: an important enrichment of the Villafranchian vertebrate faunas from the Upper Valdarno, dated in vicinity of the Pliocene/Pleistocene boundary
pp. 381-388
The Poggiorosso Locality in the Upper Valdarno (UV), discovered in September 1995 and now ready for study at the Natural History Museum in Firenze, calls attention to new developments in the chronology of the faunal successions around the Plio-Pleistocene boundary, and to the role of the Museum’s fossil collections. Old collections largely lack stratigraphic data, although in more than two centuries they provided either magnificent skeletons for exhibition in the Museum, large fossil assemblages for the research collection, or both. Of the more than 20,000 vertebrate fossil specimens at the Museum more than one fourth derive from sites in the UV basin including both large skeletons on display and the material in research collection; the last three deposits have provided almost 2,000 vertebrate specimens. The Matassino site, discovered in 1965, yielded two incomplete skeletons of young male and female elephant, partly in exhibition and the abundant assemblage referred to as the Matassino local fauna, as basal late Villafranchian. The Casa Frata site, discovered in 1978, though not as rich, yielded a similar fauna, however with some differences. The third major site is Poggiorosso, in the same clay pit as Matassino but stratigraphically some 30 m above it, and has provided more than 1,000 specimens. But not only have new localities provided a better documentation of Plio-Pleistocene history, the sites have also been more precisely placed into the chronological frame of the geomagnetic polarity time scale (GPTS) by means of magnetic reversal stratigraphy. The succession of Villafranchian faunas begins with the MN 16a Triversa faunal unit (Azzaroli, 1983); in the Upper Valdarno sequences, the Triversa age is assigned to the Castelnuovo local fauna (3.1 Ma). The embedding sequence extends from the Mammoth subchron to the end of the late Gauss magnetochron (Albianelli et al., 1997). This is succeeded by the MN 16b Montopoli faunal unit in the Lower Valdarno basin (Lindsay et al., 1980), now dated at about 2.6 Ma, at the Gauss-Matuyama boundary (the base of the late Pliocene). The Olivola faunal unit, from the North-Western Tuscany, marks the onset of the late Villafranchian; it has not been dated, but appears to be older than the Matassino fauna, which is calibrated in the UV to the end of the Olduvai chron, marking also the end of the Pliocene, and the Faella site also dated to the Olduvai which spans through 1.95-1.77 Ma. The new finds at Poggiorosso, are thus critical to the problem of faunal changes at the Pliocene/Pleistocene boundary. The Casa Frata site follows, and remains magnetically uncalibrated. Museums remain the places where old collections can be reexamined and reevaluated by means of newer collections and of new techniques, thus adding not only to our knowledge of the evolution of life and to the history of the life around us but also to the understanding of changing climates and of Earth behavior. They should not only display materials to educate the public but must continue to acquire and study new collections and to reevaluate the significance of old ones as science advances.