Recent freshwater Ostracoda and Bivalvia from Indo-Nepal border (Tethys Himalaya): Ecological implications

We report for the first time Recent ostracods and bivalves from Central Tethys Himalaya, collected from Changru village, which is situated in the Tinker valley of northwestern Nepal near the Indo-Nepal border. The specimens were collected from the surface sediments of a small pond, shaped by a small tributary of the glacier fed Tinker River. The ostracod species belonging to the families Ilyocyprididae, Cyprididae and Candonidae and one bivalve (Pisidium sp., Family Pisidiidae) have been identified. Psychrodromus olivaccus and Potamocypris villosa are being reported for the first time from India and Nepal. Several broken and unidentifiable gyrogonites of charophyta were also recovered. The ostracod sample, as a whole, points to a shallow freshwater lake environment influenced by slowly running carbonate rich waters under cool temperatures, low mineralization and sparse vegetation. This is in accordance with the occurrence of Pisidium, which is commonly associated with ostracods in the freshwater lakes and streams. The ostracod fauna shows affinity with the fossil and extant forms recovered from the Higher and Tethys Himalaya of NW India. This opens a new opportunity for studying ostracods in the Indian Central Himalaya - a region which otherwise has been ignored until now.

Some freshwater ostracods (Crustacea: Ostracoda) from South Wales

As background to a study of the application of astracods in environmental archaeology, a number of sites in South Wales were visited and sampled. Sites included seven broad environmental categories consisting of lakes, permanent ponds, non-permanent ponds, semi-static canals and reens (drainage ditches), non-permanent small lotic water-bodies, permanent fast-flowing waters and wells. In all, twenty-three species were recorded, and with one exception all belonged to the predominately freshwater Cypridoidea. Overall the most commonly encountered species in South Wales was Cypria ophthalmica. Comparing finds with earlier records, it would appear that Ilyocypris bradyi, Candona pratensis, Eucypris lilljeborgi, Herpetocypris chevreuxi, Potamocypris variegata, P. similis and P. pallida are new additions to the Welsh fauna.

An ecological study of seasonal distribution of Ostracoda, Solomons Island, Maryland, region

The determination of the distribution and seasonal fluctuations of ostracodes living in the littoral zone directly in front of the Chesapeake Biological Laboratory has been attempted in the present study. Samples taken in other parts of the Chesapeake Bay and around Solomons harbor, show that other species of ostracodes exist but these forms have not been considered in the two-year study here reported. The seasonal distribution of the species was compared with hydrographical records furnished for the same period by the Chesapeake Biological Laboratory in order to determine the correlation between ecological factors and seasonal fluctuations in numbers and species of Ostracoda.

Identification of biodiversity and distribution pattern of benthic Foraminifera and Ostracoda in continental shelf sediments of the Oman Sea

Biodiversity and distribution of benthic Foraminifera and Ostracoda in the continental shelf sediments of the Omman Sea was studied in order to indicating of the composition of benthic foraminiferal and ostracodal communities and determining of their relationship with the environmental factors of the Omman Sea. Sediment samples were gathered in winter 2006 from twelve stations ranging in depth from 30 to 103 meters. Environmental factors including depth, temperature, salinity, dissolved Oxygen and pH were measured with a CTD system during sampling time and grain size and total organic matter were measured in laboratory. From the overall 57 benthic foram species, there were 52 identified species belong to 25 genera of 16 families. The cosmopolitan foraminifer, Ammonia beccarii, was common in all sampling stations. The composition of benthic foram communities had a highly positive correlation with depth, salinity and total organic matter. From the overall 30 ostracod species, there were 26 identified species belong to 22 genera of 13 families. Diversity and aboundance of ostracoda of the Oman Sea decreased from east to west and from south to north but increased slightly in the northwest (near the Strait of Hormoz). Ostracoda of the genus Propontocypris were common in all sampling stations but the genera Cyprideis, Paradoxostom and Hemicytheridea were rare in the Oman Sea. Diversity and aboundance of ostracoda in northern regions were less than southern and were less than foraminifera too. The composition of ostracodal communities had a highly positive correlation with dept, salinity and grain size. Biodiversity and distribution pattern of benthic foraminifera and ostracoda were being different in various sampling stations, especially between northern and southern regions. Water depth, salinity and structure of the sediments were the most important abiotic factors controlling the distribution pattern of benthic foraminifera and ostracoda in the Omman Sea. None existence or rare observation of structural abnormalities and oil polluted individuals in the vicinity of all sampling stations, resulted to the "clean" benthic environment of the Omman Sea.

Tonnacypris glacialis (Ostracoda, Cyprididae):taxonomic position, (palaeo)ecology, and zoogeography

The freshwater ostracod Tonnacypris glaciallis (Sars, 1890) is reported from the European Pleistocene for the first time. The historical allocation of the species is discussed, and the species composition and characteristics of Tonnacypris is Diebel & Pietrzeniuk (1975) and its phylozoogeography are considered. The significance of T. glacialis is reviewed, particularly from the viewpoint of the possible implications of parthenogenesis (and occasional-male production) for the Quaternary history of the genus, and for the use of the species in palaeoenvironmental reconstruction. It is suggested that the Pleistocene fossil occurrence of I: glacialis in modern temperate latitudes is a robust indicator of mean summer temperatures of 6 degrees C.

On the first terrestrial ostracod of the Superfamily Cytheroidea (Crustacea, Ostracoda): description of Intrepidocythere ibipora n. gen. n. sp from forest leaf litter in Sao Paulo State, Brazil

Of the three superfamilies of Ostracoda present in fresh water, only the Cytheroidea had thus far no records in terrestrial environments. Here, we report on a new genus and species, Intrepidocythere ibipora n. gen. n. sp., of the ostracod superfamily Cytheroidea, from forest leaf litter in Sao Paulo State, Brazil. Judging from morphological similarities, this new genus is believed to be closely related to the genus Elpidium. Possible pathways that led to the colonisation of terrestrial habitats are discussed, and an overview is given on the distribution of the known terrestrial ostracod lineages. The present findings strengthen the idea that terrestrial ostracods are more common than previously thought, at least in tropical areas.

Observations of loxocythere (loxocythere) ouyenensis (chapman, 1914) (ostracoda) from the cenozoic of S.E. Australia with comments on species attributed to microcytherura müller, 1894 and hemiparvocythere hartmann, 1982 from Australian and New Zealand ma

The type material of Loxocythere (Loxocythere) ouyenensis (Chapman, 1914) from mid Cenozoic strata of the Mallee Bore No. 11 in the Murray Basin, S.E. Australia is partially redescribed and refigured. This species belongs to a discrete group of large elongate Cenozoic fossil and living Loxocythere species, the carapaces of which possess sub-rectangular inner margin outlines, and broadly rounded posterior extremities. Some much smaller but otherwise very similarly shaped species, that have previously been placed under the genus Microcytherura (i.e. Microcytherura? peterroyi Yassini and Jones, 1995) or the genus Hemiparvocythere Hartmann, 1982 (i.e. Hemiparvocythere Iagunicola Hartmann, 1982), are also known from marine Cenozoic strata and modern seas of the Australasian region. There is a marked difference in the shape of the inner margin between this group of small Australasian forms and European species of Microcytherura s.s .. The former have broadly rounded posterior inner margins, whilst the latter have acutely rounded posterior inner margins. The latter also usually present posterior extremities located well below mid carapace height. It is here argued that this difference in inner margin shape between smaller Australasian species such as Microcytherura? peterroyi, and European species of Microcytherura s.s ., suggests that there is not a direct phylogenetic relationship between these two species groups.

Description of loxocythere (novoloxocythere) pelius subgen. sp. nov. (ostracoda) from the cenozoic of S.E. Australia with comments on species of antarctiloxoconcha hartmann, 1986 and loxoreticulatum benson, 1964 from Australian and Antarctic marine waters

Loxocythere (Novoloxocythere) pelius subgen. et sp. nov. is described from Upper Miocene strata of the Port Phillip and Western Port Basins. Victoria. It has its acme in shallow open marine facies of latest Miocene (Cheltenhamian) age. This species, along with Loxocythere (Novoloxocythere) kerryswansoni Yassini and Jones, 1995, forms a discrete group of rotund Australian Loxocythere species that possess posterior extremities in both valves that are positioned well above mid carapace height (i.e. adjacent to dorsal margin). This feature along with a sub-triangular inner margin outline, defines a carapace shape that is distinct from that of rotund species of Loxocythere (loxocythere) Hornibrook, 1952 and Antarctiloxoconcha Hartmann, 1986. The type species of Antarctiloxoconcha – A.frigida (Neale. 1967), possesses internal carapace features that are very similar to the type species of Loxocythere - L. crassa Hornibrook, 1952. Both have relatively short carapaces and sub-quadrate inner margin outlines with posterior extremities in both valves positioned below mid carapace height. Species of Loxocythere (Novoloxocythere), in particular L. (N.) kerryswansoni, have a carapace shape that is transitional between Loxocythere and Loxoreticulatum Benson, 1964. Species of Loxoreticulatum generally possess a sub-parallelogram shaped carapace/inner margin and arched median hinge element. The latter feature is distinct from the mostly straight median hinge elements of Loxocythere (Loxocythere) and Loxocythere (Novoloxocythere) species. Species of Loxocythere (Novoloxocythere) are also readily distinguishable from relatively elongate species of Loxocythere, such as L. (L.) hornibrooki McKenzie, 1967, as the latter possess long (for genus), sub-rectangular shaped carapaces/inner margin outlines and posterior extremities below mid height.

Ostracoda from Lee Point on Shoal Bay, Northern Australia: part 3, podocopina (cytheracea)

The littoral environments present in Shoal Bay, Northern Territory (Australia) show a high diversity of ostracods cytheráceos (51 genera and 97 species). Probably this diversity is due to three factors: (1) marine environments warm and well oxygenated leading to a high level of biological productivity, (2) shallow marine environments favorable for the accumulation of material conchífero post mortem, and (3) a location central in the way of dispersal on the continental shelf between the regions of the Pacific and Southeast Asia. A particular feature of this fauna Cytherscea is that some genres, such as Alocopocythere, can be traced back to the Cretaceous when it first appeared in the shallow waters of the Tethys. In this overlay component of the ancient ostracods are the dominant fauna in partnerships of the modern Indo / Pacific, such as gender Keiji. While the Cytheracea ostracods are the dominant groups, especially the Cypridacea marine Bairdiacea and Plstycopina, are well represented and are quite different (fide Whatley et al., 1995, 1996). We describe here a new genre, Paraxestoleberis, and 15 new species: Dentibyíhere multituberosa, Dampiercythere papillolineata, Neocyíheromorpha papilloporosa, Loxoconcha catasíeros, Semicyrherura gamma, Callistocyíhere cookei, Loxocorniculum koolpionyahensis, Keúia interim, K. profundosculpia, K. parademissa, Quasibradleya leepoiníensis, Actinocyíhereis gippsi, Henryhowella sinespinosa, Poníicocyíhereis spatulospinosa and Paraxestoleberis posteroacuminata. Due to the limited material obtained, 16 species are kept in open nomenclature: Bythoceratina sp. Corallicyíhere sp. Venericythere sp. Tanella sp. Loxocorniculum sp. 1 L. sp. 2, Gambiella sp. Javanella sp. Paradoxostoma sp. Neomonoceratina sp., Bradley (sl) sp. Echinocytbereis (sl) sp. Plaíycyíhereis? sp. Alocopocyíhere sp. Xestoleberis sp. and Paraxestoleberis sp. The remaining 66 species have been described previously in other areas.

Referral of the Halocypridina Thaumatocypris (Miocene, Australia) to the Cladocopina (Ostracoda, Halocyprida)

B. K. Nadeau in 1955 identified as Thaumatocypris ostracodes from the middle Miocene Glenample Clay of Victoria, southeastern Australia. Nadeau's collection of Ostracoda from the Glenample Clay was located in the collections of the Museum of Victoria, Melbourne. Examination of that material indicates that the Glenample Clay specimens attributed by Nadeau to Thaumatocypris belong to Polycope sanctacatherinae Whatley & Downing 1983. As a result, it is concluded that Thaumatocypris has not been collected in the Miocene of Australia. Furthermore, in a broader  biostratigraphic/palaeobiogeographic context, the result confirms that no member of the Suborder Halocypridina has been reported so far from the Tertiary Period.

Review of Alataleberis McKenzie and Warne, 1986 and description of Alatapacifica gen. nov. (Ostracoda, Crustacea) from the Cenozoic of Australasia

Species originally assigned to the pterygocytherine genus Alataleberis by McKenzie & Warne, 1986 are placed here in two genera—Alataleberis sensu stricto and Alatapacifica gen. nov. Alataleberis species possess poorly defined dorsal ridges marked by a few spines in adult specimens and lack a subcentral tubercle. Alatapacifica species possess well-developed and buttressed dorsal ridges and a well-developed subcentral tubercle. Pterygocytherine genera/species groups recognized here from the southwest Pacific region are Alataleberis, Alatapacifica (septarca and robusta species groups), Alatahermanites Whatley & Titterton, 1981 and the velivola species group of Pterygocythereis Blake, 1933.