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The relationship between ostracod and macrophyte communities has been seldom studied, especially in urban parks. The main purpose of this research is to explore such a relationship in the area of Rome, and in particular in the Appia Antica Regional Park (Rome, Italy), to provide information about the environmental characteristics influencing both the assemblages and to document for the first time the distribution of freshwater ostracods in an area inside the city of Rome. The survey has considered different water bodies: springs, channels, ditches and a pond. Chemical and physical parameters were measured during the ostracod sampling in 13 sites during the 4 different seasons. The ostracod assemblage includes 11 species whereas the macrophyte community is formed by 17 species. Their link with the measured abiotic parameters has been studied through several statistical analyses: cluster analysis, non-metric multidimensional scaling and canonical correspondence analysis. The results clearly separate the investigated area in one sector where COD and phosphates are the driving factors and another sector where inorganic nitron ions, pH and conductivity are the main influencing factors. To better understand the ostracod-macrophyte interaction, Spearman rank-order correlation analysis was performed, confirming such a link. Although the macrophyte community is clearly affected by human pressure, the relationship with the ostracod assemblages seems well established and identified by exclusive pairs or groups of species. Among them, the Cypria lacustris-Lemna minuta duo is of considerable importance, being L. minuta an exotic species, known as an invasive weed in some areas of Europe and spread in Italy only recently. The fact that the 13 sites were characterized by different public access regulation has been partially mirrored by both ostracod and macrophyte distribution since the majority of the sites characterised by the highest diversity are those with restricted access. In general, notwithstanding the anthropic pressure, the occurrence of different kinds of water bodies has allowed the development of ostracod and macrophyte associations, which are rarely represented in an urban park.

Freshwater ostracod assemblages from San Demetrio Synthem (L’Aquila Basin, central Apennines, Italy), dating back to the late PiacenzianGelasian, are studied. Six genera and eight species are recognised, six of which are new: Caspiocypris amiterni Spadi & Gliozzi sp. nov., C. bosii Spadi & Gliozzi sp. nov., C. nicandroi Spadi & Gliozzi sp. nov., C. vestinae Spadi & Gliozzi sp. nov., Cypria bikeratia Spadi & Gliozzi sp. nov., and Ilyocypris ilae Spadi & Gliozzi sp. nov. Additionally, one fragmentary valve referred to Paralimnocythere cf. P. dictyonalis Medici, Ceci & Gliozzi, 2011, one valve ascribed to Amnicythere ex gr. stanchevae Krstic, 1975, one fragment tentatively identified as Limnocythere? sp. and four poorly preserved valves of Cypridoidea indet. were also recovered. The genus Caspiocypris is revised, and an emended diagnosis is provided. Comparisons are made with the most similar co-generic species occurring in the Neogeneof Italy and the Paratethyan domain. The ostracod fauna of the San Demetrio Synthem shows the greatest affinity at the generic level with the Pontian (MessinianZanclean) ostracods of the Pannonic, Dacic and Euxinic Basins. To explain thisaffinity, two hypotheses are discussed: (1) passive dispersal of Paratethyan forms into the Italian PlioPleistocene palaeolakes; and (2) endemic evolution of several species in different PlioPleistocene palaeolakes from the Paratethyan likelate Messinian Lago-Mare ostracod fauna of the Palaeomediterranean area.

The Tiberino Basin is a wide Plio–Pleistocene intermountain basin located in central Apennine (central Italy). Its sedimentary infill is made of a thick succession of Pliocene–early Quaternary continental deposits, the oldest of which can be referred to the Fosso Bianco Formation, composed of grey clays deposited in a huge (at least 500 km2) and relatively deep (not less than 50 m) lake, the Palaeolake Tiberino. We analyse the lacustrine ostracod assemblages from the Fosso Bianco Formation and provide descriptions of five new species included in the subfamily Candoninae (Caspiocypris basilicii sp. nov., Caspiocypris perusia sp. nov., Caspiocypris posteroacuta sp. nov., Caspiocypris tiberina sp. nov. and Caspiocypris tuderis sp. nov.)) and one new species included in the subfamily Limnocytherinae (Paralimnocythere umbra sp. nov.)). The five species of Caspiocypris seem to represent a species flock, i.e. Caspiocypris includes a group of closely related species characterized by monophyly, endemism and speciosity, confirming the ‘ancient lake’ nature of the Palaeolake Tiberino during the Piacenzian–Gelasian. The ostracod assemblage points to a relatively deep-water and low energy lacustrine environment marked by a high level of endemism.

The living euryhaline species Cyprideis torosa (Jones) undergoes morphometric variations in size, noding and sieve-pore shape linked to environmental parameters. In particular it is known that salinity values around 8–9‰ represent the osmoregulation threshold and the turning point between smaller and greater valves and prevailingly noded as opposed to un-noded valves. Here, a character never studied before is analysed: the relationship between salinity and the C. torosa valve outlines, especially the morphology of the ventral border. Geometric–morphometric analysis was carried out on different populations of C. torosa collected in oligohaline (Massaciuccoli marsh, Tuscany, and Lake Trasimeno, Umbria) and hyperhaline waterbodies (Trapani–Paceco salt pans, Sicily). The results indicate that the species displays two morphotypes: a dominant one, characterized by a straight ventral border; and a morphotype with a sigmoidal profile ventral border. This latter morphotype seems to be related to higher salinity: the oligohaline waters are characterized only by C. torosa individuals with straight ventral outline, while the hyperhaline environments are marked by the occurrence of 17.6% of sigmoidal individuals. Furthermore, the sigmoidal ventral border is more emphasized in males than in females.

As a result of the use of geometric morphometrics, multivariate statistics and classical morphological observations the authors propose a taxonomic revision of the Neogene Italian Cyprideis species. On this basis, the Cyprideis valves collected in Tortonian, Messinian and Pliocene brackish deposits of Italy are referred to 12 species, six of which are new: Cyprideis alexandri nov. sp., Cyprideis arvedoi nov. sp., Cyprideis lepianensis nov. sp., Cyprideis rooki nov. sp., Cyprideis strollae nov. sp., and Cyprideis toscana nov. sp. Some species are rather widespread in the Italian Peninsula (Cyprideis ruggierii Decima and Cyprideis crotonensis Decima) or even in the whole Palaeomediterranean (Cyprideis agrigentina Decima and Cyprideis anlavauxensis Carbonnel). For C. ruggierii, C. agrigentina and C. crotonensis, a phyletic relation is suggested. The new species are confined both geographically and stratigraphically in several Tuscan athalassic brackish basins, suggesting endemic speciation similar to those occurring in ancient lakes.

Late Miocene brackish ostracods and molluscs collected in three Italian basins show noticeable differences in their taxonomic composition, despite their capability of dispersing across wide geographic areas. In the Venetian-Friulian Basin (northern Italy), the upper Tortonian sediments contain oligotypic ostracod assemblages including Hemicyprideis dacica dacica, Hemicytheria pejinovicensis, and Loxoconcha cf. L. josephi and few gastropods referable to Planorbidae and Stenothyroides, which are typical of the central Paratethys. In central Italy, the brackish ostracods and molluscs recovered from upper Tortonian-lower Messinian deposits from four Tuscan basins (Volterra-Radicondoli, Velona, Baccinello-Cinigiano, and Valdelsa) display high affinity at a generic level but strong endemicity at a specific level. At Cessaniti (southern Italy), the upper Tortonian unit contains oligotypic brackish ostracods and molluscs: Mediocytherideis (Sylvestra) posterobursa, Cyprideis ruggierii, Loxoconcha cf. L. biformata, and Zonocypris membranae quadricella characterise the ostracod fauna, while Granulolabium bicinctum and Hydrobia frauenfeldi are the dominant molluscs. The recovered ostracods have a strong affinity with brackish species from central and eastern Palaeo-Mediterranean areas, whereas the molluscs present a Paratethyan origin. Despite the fact that the basins are all brackish and partly coeval, the systematics of these assemblages highlights the absence of common species among the three studied areas. Geochemical analyses (stable isotopes and trace elements) are performed on ostracods, and 87Sr/ 86Sr ratios are established in molluscs and echinoids. The results suggest brackish environments with different compositions and origins of solutes in the three different areas. The Tuscan basins are characterised by brackish waters, with NaCl-enriched waters coming from aquifers of Triassic evaporite bedrock. The brackish deposits of the Venetian-Friulian Basin and Cessaniti are true marginal marine environments, although the northern basin may have been influenced by both the Paratethyan Sava Basin and the northern portion of the Palaeo-Mediterranean water bodies. © 2012 Elsevier Masson SAS., This research has been supported by the Istituto di Geologia Ambientale e Geoingegneria (IGAG), CNR of Roma (Italy), Commessa TA.P05.009, by the research grants to Elsa Gliozzi provided by the Department of Earth Sciences of University Roma Tre, and the research grants to D. Esu provided by ‘‘Sapienza’’ University of Roma. P. Anado´ n’s work was supported by research grant CGL 2008-00594, Ministerio de Ciencia e Innovacio´ n, Spain.

In questo lavoro vengono studiati il genere Mediocytherideis Mandelstam, 1956 con i suoi sottogeneri Mediocytherideis s.s. e M. (Sylvestra) Doruk, 1973 e vengono fornite, per entrambi, le diagnosi emendate. Vengono istituite sei nuove specie: Mediocytherideis (Sylvestra) etrusca nov. sp., Mediocytherideis (Sylvestra) fossata nov. sp., Mediocytherideis (Sylvestra) ornata nov. sp., Mediocytherideis (Sylvestra) punctata nov. sp., Mediocytherideis (Sylvestra) sulcata nov. sp. e Mediocytherideis (Sylvestra) tetrafoveolata nov. sp., rinvenute nei sedimenti messiniani salmastri dei bacini di Volterra-Radicondoli e di Velona (Toscana, Italia centrale). Inoltre, a causa dello scarso materiale rinvenuto, sono state lasciate in nomenclatura aperta tre forme di Mediocytherideis s.l. provenienti dai sedimenti salmastri messiniani del bacino di Velona, dalla sezione del cimitero di Taranta Peligna (Montagna della Majella, Italia centrale) e dalla sezione Trave (Ancona, Italia centrale). Viene effettuata, inoltre, una revisione delle specie di Mediocytherideis s.l. note fino ad oggi in letteratura, ponendo particolare attenzione alla loro distribuzione stratigrafica e, sulla base di questi dati, vengono discusse l’origine e la distribuzione stratigrafica e paleobiogeografica del genere. Il database mostra che sia Mediocytherideis s.s. sia M. (Sylvestra) appaiono più o meno contemporaneamente nell’area mediterranea e in quella paratetidea durante il Serravalliano, quando i due paleodomini non erano ancora separati. Dopo la chiusura della connessione tra Mediterraneo e Paratetide, avvenuta durante il Serravalliano superiore, Mediocytherideis s.l. continuò ad evolversi, con differenti specie, nelle due paleobioprovince. Nella Paratetide le specie di Mediocytherideis s.l. furono sempre caratteristiche di ambienti salmastri o, nei primi momenti della storia evolutiva del genere, di ambienti marini poco profondi stressati; nel Mediterraneo, al contrario, fin dalla sua prima comparsa il genere diede origine a differenti specie adattate o ad ambienti marini poco profondi o ad ambienti salmastri. Sfortunatamente, le conoscenze troppo frammentarie sulle specie di Mediocytherideis s.l. rendono impossibile definire il centro di origine del genere. Allo stesso tempo, è impossibile stabilire se le specie salmastre mediterranee di Mediocytherideis s.l. si originarono da uno stock mediterraneo o da forme salmastre paratetidee migrate verso ovest attraverso la dispersione passiva. The genus Mediocytherideis Mandelstam, 1956 with its subgenera Mediocytherideis s.s. and M. (Sylvestra) Doruk, 1973 are here revised and the emended diagnosis of the two subgenera are given. Six new species have been introduced: Mediocytherideis (Sylvestra) etrusca nov. sp., Mediocytherideis (Sylvestra) fossata nov. sp., Mediocytherideis (Sylvestra) ornata nov. sp., Mediocytherideis (Sylvestra) punctata nov. sp., Mediocytherideis (Sylvestra) sulcata nov. sp. and Mediocytherideis (Sylvestra) tetrafoveolata nov. sp., coming from the Messinian brackish sediments of the Volterra-Radicondoli and Velona basins (Tuscany, central Italy). Three more taxa are described, left in open nomenclature, coming from the Messinian brackish sediments of the Velona Basin, the Taranta Peligna cemetery section (Majella Mt., central Italy) and the Trave Section (Ancona, central Italy). An overview of the known Mediocytherideis s.l. species is given and the stratigraphic distribution and palaeobiogeography of this genus is discussed. The database shows that both Mediocytherideis s.s. and M. (Sylvestra) appear, more or less at the same time, either in the Mediterranean and in the Paratethys regions during Serravallian, a time interval in which these two palaeodomains were not yet divided. After the closure of the Mediterranean-Paratethys connection, occurred during the late Serravallian, Mediocytherideis s.l. continued to spread in each bioprovinces: in the Paratethys it is characteristic of brackish environments or, at least at the very beginning of its evolutive history, of shallow stressed marine environment; in the Mediterranean, on the contrary, since its appearance the genus gave rise to different species adapted to shallow marine environment or brackish environment. Unfortunately the too much-fragmented knowledge on Mediocytherideis s.l. species prevents the recognition of the centre of origin of the genus. Similarly, it is impossible to establish whether the brackish Mediterranean Mediocytherideis s.l. evolved from a Mediterranean stock or from Paratethyan brackish species migrated westwards by passive dispersal.

The Late Miocene Italian brackish Loxoconchidae are herein discussed and illustrated. Three genera and two subgenera have been recognized in the brackish Italian basins: Loxoconcha , Loxocorniculina , Loxoconchissa ( Loxoconchissa ) and Loxoconchissa ( Loxocaspia ). Taking into account the diagnostic characters of several Loxoconchidae genera, in this paper Loxocorniculina is raised at a generic rank, Loxocaspia is confirmed as a subgenus within genus Loxoconchissa and several new species are established: Loxoconchissa ( Loxoconchissa ) kinoi nov. sp., Loxoconchissa ( Loxocaspia ) cosentinoi nov. sp., Loxoconchissa ( Loxocaspia ) nuda nov. sp., Loxoconchissa ( Loxocaspia ) punctata nov. sp., Loxoconchissa ( Loxocaspia ) reticulata nov. sp., Loxoconchissa ( Loxocaspia ) tuberosa nov. sp. and Loxoconchissa ( Loxocaspia ) velonae nov. sp. Loxocorniculina is a typical Paratethyan genus which widespread into the Palaeo-Mediterranean during the late Messinian Lago-Mare event. Loxoconchissa was known to be widespread only in the Paratethyan realm and in this paper it is signalled for the first time in the Late Tortonian-early Messinian of Italy. The palaeobiogeography of these genera is discussed and the observed continuous distribution of Loxocorniculina against the disjunct distribution of Loxoconchissa leads to suggest that this latter genus underwent a passive dispersal via aquatic birds.