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Three closely allied shallow marine taxa, Neohornibrookella sorrentae (Chapman and Crespin), Neohornibrookella glyphica (Neil), and Neohornibrookella nepeani sp. nov. are recorded from latest early Miocene to late Pliocene strata in southeastern Australia. These taxa, together with Neohornibrookella quadranodosa (Holden) from the Miocene of Midway Island (Northwestern Hawaiian Islands), form a morphologically distinct group of relatively large species (the sorrentae-group) within the genus Neohornibrookella Jellinek. Latitudinal expansion of the subtropical and warm-temperate climatic belts together with the influence of warm western boundary surface currents associated with the North and South Pacific gyres, are likely to have played key roles in the Miocene dispersal of this species group. Species of the sorrentae-group first migrated south from equatorial west Pacific regions into southeastern Australia during the early Miocene, under the influence of the East Australian Current. During three time intervals (i) latest early Miocene, (ii) latest late Miocene and (iii) earliest late Pliocene, forceful pulses of the East Australian Current played a significant role in propelling the widespread distribution of thermophilic Neohornibrookella species across southeast Australian shallow marine realms. During intervening middle and late Miocene times, Neohornibrookella species are only sporadically present across the Bass Strait region of southeast Australia, indicating a weaker East Australian Current influence and the cooling influence of coastal upwelling. During the mid early Pliocene Neohornibrookella species disappeared from the western Bass Strait region, suggesting the complete exclusion of East Australian Current waters from this region. This was probably due to the counteracting influence of the eastward flowing Zeehan Current (extension of the Leeuwin Current) impinging on the western Bass Strait region. This mid early Pliocene palaeobiogeographical partition in Bass Strait, defined by the distribution of sorrentae-group species, is here termed the Bassian Gateway. The two species, N. sorrentae and N. glyphica, occur concurrently during the mid Miocene in southeast Australia, but are associated with different lithofacies. It is hypothesised that there is a heterochronic evolutionary relationship expressed in the ornament of these two species. The thaerocytherid genera Neohornibrookella Jellinek, Tenedocythere Sissingh and Bosasella Bonaduce are here included in the new ostracod subfamily Tenedocytherinae.

Five new genera of cytheracean Ostracoda are described from the S.W. Atlantic area. They are: Austrocytheridea and Papillosacythere, which belong to the Cytherideinae and Neocytherideinae respectively, and Austroaurila. Falklandia, and Meridionalicythere, which are all members of the Hemicytheridae.

From a numerical analysis of deep water Neogene and Quaternary Ostracoda from D.S.D.P. sites in the S. W. Pacific, it is shown that the Miocene to Quaternary interval saw a large scale invasion by bathyal stocks of the abyss. This invasion was progressive and cumulative and resulted in abyssal faunas being much more diverse in the Quaternary than they had been in the Miocene. This major palaeoecological shift also occasioned a concommitant decline in bathyal faunas over the same interval. The breakdown of bathyal and abyssal isolation resulted from the Miocene onwards, in a progressive increase in the number of species which were able, contemporaneously, to live at both bathyal and abyssal palaeodepths.The study shows deep water faunas of this age to be much more diverse than previous studies have indicated. Ninety-one genera with autochthonous deep water species are encountered in this study. These genera are listed with the numbers of species of each genus and their depth distribution for Miocene, Pliocene and Quaternary respectively. Overall species diversity declines from the Miocene to the Pliocene but steeply increases into the Quaternary. It is suggested that the Pliocene impoverishment may in part be an artefact, occasioned by abnormally high Miocene diversity.It is shown that the phenomena outlined above are, to varying degrees, illustrated by all of the 6 groups into which the fauna is divided. It is suggested that certain of these phenomena, such as the major downslope migration from the Miocene onwards, may be detectable in other parts of the world’s oceans.

The Bairdiinae of the littoral and inner shelf of the Solomon Islands are both abundant and diverse. A total of 21 species have been recovered of which 13 are described as new 2 further species are left in open nomenclature. The new genus Mydionobairdia is erected, based on Triebelina schyroconcha Maddocks, 1969. The new species are: Bairdoppilata paraalcyonicola, B. paracratericola, Neonesidea paragierloffi, N. vscripta, N.? crepidula, N.? rara, Paranesidea bipustulosa, P. corbita, P. equipunctata, P. petalona, P. stricta, P.? confusa and P.? paucipunctata. Some of the difficulties involved in distinguishing species of Neonesidea and Paranesidea are discussed.

It has been shown that during Jurassic and Cretaceous kenoxic events, while other groups of benthonic Ostracoda severely decline and eventually disappear, the Platycopina tend to survive. The survival of the platycopids is attributed to their being filter feeders who, in dysaerobic conditions manage to obtain sufficient oxygen by virtue of the greater volume of water which they circulate across their respiratory surface in the course of their normal feeding behaviour. The podocopid ostracods, which are predators, scavengers and deposit feeders, are unable to survive the diminished oxygen concentrations which characterise these events. The platycopid genus Cytherella is shown to dominate the oxygen mininmum zone in two different parts of the Atlantic at the present day.

Sixteen species of marine Cypridoidea belonging to seven genera and a rather small fauna of nine platycopid and two cladocopid species from the Solomon Islands are described. Nine species are described and illustrated as new. They are: Paracypris contracta, Triangulocypris teeteri, T. umbonata, Aglaiocypris supercylindrica, Argilloecia teres, Propontocypris paracrocata, P. supertrigonella, Cytherelloidea asymmetrica and C. dictyotos ssp. nov. Five species have been described previously and 11 species are retained in open nomenclature. While the Cypridoidea comprise only 15% of the total fauna of 160 species recorded from the Solomon Islands, they are not insignificant and, in some environments, are among the dominant ostracods. The platycopids/cladocopids comprise only 13% of the total fauna but likewise are dominant in some environments. They are typically SW Pacific in character.

The new subfamily Nodoconchiinae of the Cytheridae Baird is erected to accommodate three genera: Austrocythere Hartmann, 1989a, Nodoconcha Hartmann, 1989a and Ectonodoconcha gen. nov.. Austrocythere seems to be known only from the type species A. reticulotuberculata Hartmann, from its type locality in the Recent Antarctic and from the Antarctic Oligocene. Nodoconcha, however, apart from its original record by Hartmann from the Antarctic as Nodoconcha minuta, has also been encountered in the Oligocene of the Antarctic. In the present study, we have identified seven species of Nodoconcha from the Maastrichtian and Danian of the Neuquén Basin, together with a new genus from the Danian, Ectonodoconcha lepidotus gen. et sp. nov.. The new species of Nodoconcha are N. polytorosa sp. nov., N. sanniosis sp. nov. and N. upsilon sp. nov., and Nodoconcha? sp. that is the possible ancestor of the entire group. Previously described species now placed in the genus are: N. paleocenica (Bertels, 1973), N. jaguelensis (Bertels, 1974) and Nodoconcha sp. (Bertels, 1974). The Nodoconcha species are divided into the Minuta and Upsilon groups.

This paper is a revision of Brady’s 1869 study of the Ostracoda of Hong Kong in ‘Les Fonds de la Mer’. In this he described the following nine new species: Cyrherella cingulata, Bairdia elegans, Bythocythere orientalis, Loxoconcha sinensis, L. hastata, Cytheridea impressa, Cythere cymba, C. euplectella and C. salebrosa. A detailed reappraisal of Brady’s original material which is deposited in the Hancock Museum, Newcastle-upon-Tyne, UK, and the Centre d’Etudes et de Recherches Scientifiques, Biarritz, France has revealed that the specimens of L. hastata are apparently lost. Holotypes and lectotypes have been designated by the authors for the other eight species. Those species which were subsequently recorded by Brady (1880) in the Challenger Report, such as C. cingulata, B. orientalis, L. sinensis and C. euplectella are demonstrated not to be conspecific with their original types first described in 1869. The following 10 species, Bythoceratina virgatella Hu, 1983 and B. cassidoidea Zhao, 1985; Cyprideis yehi Hu & Yeh, 1978, Sinocytheridea sinensis Hou. 1978, S. latiovata Hou & Chen, 1982, 5. lotjga Hou & Chen, 1982 and Eucytheridea sinobesani Hu, 1984: Cythereis subconvexa Kajiyama, 1913 and Aurila miii Ishizaki, 1968: Cythereis assimilis Kajiyama. 1913 are placed by the authors in the synonymies of Brady’s B. orientalis, C. impressa, C. cymba and C. salebrosa respectively.

Eleven species of family Hemicytheridae and seven of the family Thaerocytheridae are described. Together they comprise 14% of the total Recent ostracod fauna described from the Solomon Islands. In the main the hemicytherids are much more endemic than the thaerocytherids. Three new species have been recorded only from the Solomon Islands, and three species of Caudites, held in open nomenclature due to their rarity, are also probably endemic to the islands. Another three new species have been recorded only from Java and one species of Mimicocythere gen. et sp. nov. also occurs in Australia. The six new species described and illustrated are: Ambostracon (A.) micropapillatum, A. (A.) micromaculata, Caudites shortlandensis, ?C. atypicus, Mutilus dissimilis ssp. nov. and Mimicocythere pseudomelobesoides gen. et sp. nov. Only one of the hemicytherids, Caudites javana Kingma, occurs throughout the Indo-Pacific. It is the Thaerocytheridae, however, that are almost pandemic in tropical regions, with Tenedocythere deltoides and T. transoceanica being distributed particularly widely. A new species of the rare genus Neobuntonia, N. subalata sp. nov., only the second modern species to be described, is also illustrated.

A total of 113 species belonging to 54 genera are recovered from a study of the Maastrichtian and Danian deposits in the Cerro Azul section of the Neuqu en Basin, west-central Argentina. Of these, 9 new genera, 38 new species and 28 species in open nomenclature are recorded. These form the basis of the present study and are listed below. Genera: Phelocyprideis gen. nov., Aleisocythereis gen. nov., Apatoleberis gen. nov., Mimicocythereis gen. nov., Castillocythereis gen. nov., Hysterocythereis gen. nov., Orthrocosta gen. nov., Petalocythereis gen. nov. and Sthenarocythereis gen. nov. Species: Cytherella saraballentae sp. nov., Cytherella semicatillus sp. nov., Paracypris bertelsae sp. nov., Paracypris imaguncula sp. nov., Argilloecia abnormalis sp. nov., Argilloecia concludus sp. nov., Argilloecia hydrodynamicus sp. nov., Bythoceratina cheleutos sp. nov., Phelocyprideis acardomesido sp. nov., Eucythere dinetos sp. nov., Krithe crepidus sp. nov., Cytheropteron hyperdictyon sp. nov., Cytheropteron bidentinos sp. nov., Cytheropteron translimitares sp. nov., Aversovalva glochinos sp. nov., Eucytherura stibaros sp. nov., Hemingwayella verrucosus sp. nov., Heinia prostratopleuricos sp. nov., Loxoconcha (s.l.) posterocosta sp. nov., Keijia circulodictyon sp. nov., Keijia kratistos sp. nov., Paramunseyella epaphroditus sp. nov., Munseyella costaevermiculatus sp. nov., Ameghinocythere archaios sp. nov., Aleisocythereis polikothonus sp. nov., Castillocythereis multicastrum sp. nov., Castillocythereis albertoriccardii sp. nov., Cythereis stratios sp. nov., Cythereis clibanarius sp. nov., Cythereis trajectiones sp. nov., Henryhowella (Wichmannella) praealtus sp. nov., Hysterocythereis paredros sp. nov., Hysterocythereis coinotes sp. nov., Hysterocythereis diversotuberculatus sp. nov., Orthrocosta decores sp. nov., Orthrocosta atopos sp. nov., Orthrocosta phantasia sp. nov. and Sthenarocythereis erymnos sp. nov. The nature of the fauna and aspects of its evolution are discussed. Fil: Ceoilin, Daiane. Universidade do Vale do Rio dos Sinos; Brasil Fil: Whatley, Robin. Universidade do Vale do Rio dos Sinos; Brasil Fil: Fauth, Gerson. Aberystwyth University; Reino Unido Fil: Concheyro, Graciela. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos; Argentina

The study of the subfamily Cytheropterinae from the southern Brazilian continental shelf reveals the presence of four genera and nine species, including two newly described (Cytheropteron sudatlanticum sp. nov., Loxoreticulatum pulchrum sp. nov.) and two left in open nomenclature (Cytheropteron sp. and Kangarina sp.). All of these species are restricted to the southern part of the Southwest Atlantic Ocean and do not extend beyond the coast of Rio de Janeiro, Brazil. Three of these species (Oculocytheropteron micropunctatum, O. reticulatum, O. macropunctatum) extend beyond the southern limit of the Brazilian Province (36°S), while the others occur inside the limits of the Brazilian Province (36°S–22/21°S). The genus Loxoreticulatum, a well-known ostracod taxon from the Antarctic Peninsula, southern Argentina and Falkland (= Malvinas) Islands, is herein reported for the first time from offshore Brazil.

Warne, M.T. & Whatley, R.C. iFirst article. Description of Systenobythere gen. nov. (Ostracoda, Crustacea) from the late Miocene of southeastern Australia with comments on its problematical taxonomic and palaeoecological affinities. Alcheringa, 1–8. ISSN 0311-5518. A new ostracod genus and species, Systenobythere archboldi, is described from late Miocene open neritic strata of southeastern Australia. Specimens occur in argillaceous glauconitic sands deposited in offshore continental shelf settings that were periodically influenced by coastal upwelling. Systenobythere archboldi possesses an adductor muscle scar pattern typical of the Bythocytheridae, but has a pentodont hinge and sieve-type normal pore canals atypical of this family.

The present study is a further contribution to the systematic knowledge of the ostracods from the southern Brazilian continental shelf. Twelve species of Trachyleberididae are recorded, including the following six new taxa

In the present study, we compare modern and Quaternary ostracods from two lacustrine basins: Laguna Cari-Laufquen (41 degrees S) and Lago Cardiel (49 degrees S) in Patagonia. Taxonomic and quantitative analyses along with isotopic and chemical studies of the extant ostracod fauna indicate that distinct ostracod associations can be identified as a function of conductivity. Three ostracod associations can be distinguished: (1) springs, ponds and small creeks, characterized by low conductivity (e. g. 1015 ms cm(-1)); (2) lakes and permanent ponds, characterized by medium conductivity (e. g. 1625 ms cm(-1)) and (3) ephemeral lacustrine environments, generally characterized by higher conductivity (e. g. 16 480 ms cm(-1)) These modern ostracod associations were also identified in older sequences from sediments outcropping in the Laguna Cari-Laufquen current shoreline, as well as in sediment cores from Lago Cardiel. The predominance of Limnocythere rionegroensis Cusminsky & Whatley in the Cari-Laufquen sections suggests the development of a saline and turbid lake during the Late Pleistocene and Early Holocene, and thus higher precipitation at these latitudes. Changes in ostracod abundance and associations have been observed in Lago Cardiel during the last approximately 16 000 calibrated years BP. Conductivity is known to change as a function of the ratio of precipitation to evaporation and a decrease in conductivity from the Late Pleistocene to the Middle Holocene suggests substantial hydrological variations (i. e. increase of the precipitation/ evaporation ratio suggests minor conductivity). These two examples show that ostracods provide an excellent proxy for interpreting palaeoclimatic and palaeoenvironmental changes in Patagonia. (C) 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 103, 397-408. (Less)

The genus Praecypridea gen. nov. (Cypridoidea, Family Cyprideidae Martin, 1940) is described and thus far comprises four species: the type species Praecypridea acuticyatha (Schudack, 1998) comb. nov., Praecypridea postelongata (Oertli, 1957) comb. nov., Praecypridea suprajurassica (Mojon, Haddoumi & Charriére, 2009) comb. nov. and Praecypridea acuta (Moos, 1959 in Wicher, 1959) comb. nov. Representatives of the new genus have been described from the Middle to Late Jurassic of Europe, North America and Africa and the Early Cretaceous of South America, with other presumed representatives also occurring in the Early Cretaceous. Species of Praecypridea are considered to represent members of the ancestral lineage of the extinct genus Cypridea Bosquet, representatives of which flourished in non-marine habitats of latest Jurassic to Early Cretaceous age and account for the first period of abundance of the non-marine Cypridoidea.

The genus Semicytherura Wagner differs from all other members of the Cytherurinae in the nature and course of its inner margin/line of concrescence. The inner lamella is very wide anteriorly, while posteriorly the inner margin extends anteriorly almost to the position of the closing muscles. However, two species examined by the authors, Semicytherura clavata (Brady, 1880) and Semicytherura contraria Zhao & Whatley, 1989, from the SW Atlantic and SE Asia respectively are shown to exhibit this characteristic feature only in the male. In the female of both these species, while the anterior inner lamella is identical to that of the male, posteriorly their inner margins parallel the posterior margin. Similar sex-linkage was show in the genus Angulicytherura which is probably closer to Cytherura than Semicytherura, with a narrow and vestibulate inner lamella.

The status of thirty four species of the cytheroidean ostracod family Cytheruridae from the Neuquén Basin, west-central Argentina is reviewed. These species belong to the following nine genera: Eucytherura Müller, ranging in this study from Pliensbachian to Valanginian and represented by fourteen species; Kangarina Coryell and Fields, Aalenian-Bajocian, with a single species; Acrocythere Neale, Hauterivian, one species; Paranotacythere Bassiouni, Berriasian, two species; Procytherura Whatley, Pliensbachian to Hauterivian, twelve species; Cytheropteron Sars, Aalenian-Bajocian, one species: Eocytheropteron Alexander, Hauterivian, one species; Paradoxorhyncha Chapman, Aalenian-Bajocian, one species; and Paracytheridea Müller, Berriasian, one species. Of the three subfamilies of the Cytheruridae, the Cytherurinae, with thirty species are by far the most numerous and abundant throughout the study. The other two subfamilies, the Cytheropterinae are represented by three species and the Paracytherideinae by a single species of the nominative genus. Several of the species are very widely distributed geographically and have, for example, also been recorded from Europe; others indicate close links with South Africa and Australia. The stratigraphical ranges of certain genera have been extended as a result of this study. For example, Kangarina has not previously been recorded below the Cretaceous. The Cytheruridae are clearly the most diverse cytheroidean ostracodes in the Mesozoic of the Neuquén Basin and are more diverse than all other groups of ostracodes combined. Four new species, Eucytherura tessae, Eucytherura yunga, Procytherura amygdala and Eocytheropteron immodicus are described. Eucytherura guillaumeae nom. nov. for Eucytherura tuberculata Brenner and Oertli and Eucytherura paranuda nom. nov. for Eucytherura nuda (Brand) are proposed., Facultad de Ciencias Naturales y Museo

The taxonomic status of the Lower Cretaceous non-marine ostracode genera Hourcqia Krommelbein and Pattersoncypris Bate is discussed. From a detailed analysis of the type species of these genera, and several other species attributed to them, it was possible to conclude that both genera are invalid. Hourcqia africana Krommelbein, the type species of this genus, has an antero-ventral beak, and it is in all other respects identical to Cypridea Bosquet, and therefore should be transferred to this genus. The subspecies originally referred to as Hourcqia africana confluens Krommellbein and Weber, 1971 is subsumed within Cypridea africana. Secondly, the genus Pattersoncypris, as the result of a study of its type species, P. micropapillosa Bate, is shown to be a junior synonym of Harbinia Tsao. Both, Hourcqia and Pattersoncypris must therefore be suppressed. Cypridea africana (Krommelbein) occurs in Brazil, Congo, and Gabon in strata deposited during the rift stage, restricted to the late Barremian to ear...

Sands and gravels underlain by silts and clays, known as the Burtle Beds, from the Somerset Levels of South West England have been examined in a specially excavated pit. The Mollusca, Foraminifera and the Ostracoda, and the sparse macroscopic plant remains included in the deposit, all indicate a prgressive marine transgression in which water temperatures obtained approximating to those of the present sea in the adjacent Bristol Channel. The deposits are shown to be estuarine/marine near shore and intertidal sediments of interglacial age. Radiometric assays and studies of palaeomagnetism have failed to indicate clearly which interglacial marine transgressive phase is involved. Geomorphological considerations supported to some extent by the Ostracoda suggest that a last interglacial (Ipswichian) age is more likely than an earlier (Hoxnian?) date. Estimates of the height of sea levels involved are, of necessity, based on evidence which cannot be regarded as wholly reliable. Having regard to the environmental conditions indicated by the included fauna, and making allowance for post depositional erosion, it is suggested that mean sea level at the height of the ‘Burtle’ transgression was between 9 and 12 m above that of the present (O. D.). Assuming a similar tidal range to that of today, a MHWST (Mean High Water of Spring Tides) level of between 15 and 18 m above O. D. is indicated

The genus Rostrocytheridea is strictly gondwanine in its distribution and, in Argentina, is shown to be restricted to Patagonia. Of the six recorded Argentinian species, five are restricted to the southern part of South America: Rostrocytheridea opisthorhynchus nov. sp. (late Tithonian-Berriasian), Rostrocytheridea sp. (Valanginian), Rostrocytheridea cerasmoderma nov. sp., Rostrocytheridea covuncoensis Musacchio (Hauterivian) and Rostrocytheridea? sp. (Campanian). One species, Rostrocytheridea ornata Brenner and Oertli, is of much wider distribution, occurring in the Neocomian of South Africa and the Hauterivian of central-west Argentina. In Australia, the genus first appears in the Albian-Cenomanian and ranges up to the Santonian with two species: Rostrocytheridea canaliculata Bate and Rostrocytheridea westraliensis (Chapman). The youngest record of the genus is R. hamiltonensis Fauth and Seeling from the Middle to Upper Campanian of the James Ross Basin, Antarctic Peninsula. The implications for intercontinental correlation and the reconstruction of palaeo-migration routes are considered. Copyright © 2007 John Wiley & Sons, Ltd.

This paper demonstrates that Arculicythere Grekoff is a widespread taxon in the uppermost Upper Jurassic and Lower Cretaceous of Gondwana. It occurs in Madagascar, India, Israel, South Africa, the Falklands Plateau, Argentina and Australia. The earliest record is from the Upper Tithonian of Madagascar but the most profuse occurrences are in the Albian, when the genus was very widespread around Gondwana. Its distribution seems to be associated with a major southern Gondwana seaway, and the genus provides additional proof of the existence of this corridor. Unlike another endemic gondwanine genus, Majungaella Grekoff, which ranged from earlier in the Jurassic but extended into the Neogene in the Antarctic, or Rostrocytheridea Dingle that survived into the Campanian of the Antarctic, Arculicythere seems to have become extinct in the Albian.

The palaeozoogeography of Lower Jurassic (Pliensbachian-Toarcian) Ostracoda is studied in terms of faunal similarity between 13 geographical areas. A list of 270 marine ostracod species from Europe, North Africa and North America has been compiled and subjected to quantitative analysis (using multivariate methods) in order to ascertain the degree of similarity between Spanish assemblages and those described from these areas. The cluster analysis demonstrates that degree of similarity generally reflects proximity in palaeogeographical position. The results indicate extensive intercommunication of taxa between the basins, and also the absence of clear differentiation between Tethyan and Boreal faunas.

Majungaella Grekoff is shown to be the only member of the once dominant ostracod family Progonocytheridae, Progonocytherinae to survive the Jurassic and also to survive the Cretaceous–Tertiary boundary event. In the Jurassic, Majungaella had a northeastern gondwanine distribution, occurring only in India, Africa and Madagascar. However, during the Neocomian it appears in South America where it extends to the Maastrichtian, while in Australia it first appears in the Aptian and ranges up to the Campanian. Its last records in Africa are in the Cenomanian of South Africa and the Santonian of south-western Africa. This southward shift into higher latitudes was probably due to an increasing cryophilia and, although this may have also been prompted by competitive exclusion by better adapted, newly evolved taxa, it is difficult to demonstrate this due to the universal distribution of most Late Mesozoic ostracod genera. Whatever the reason, Majungaella seems to have become, during the Cretaceous, increasingly adapted to living in high-latitude shallow seas and this adaptation is advanced as the prime reason why the genus, alone among the progonocytherids was able to survive both the post-Cretaceous global cooling and Antarctic palaeoenvironments into the Late Neogene. Eocene, Oligocene and Pliocene occurrences of Majungaella in the Antarctic are investigated and it is concluded that the genus is in situ in all instances and that, especially in the two latter cases, it lived in water temperatures very much lower than those of its Mesozoic forebears.

A small fauna of three species of non-marine cypridacean Ostracoda has been recovered from the Basgo Formation of the Ladakh Molasse in the North Western Himalaya, India. All three species are new and are described herein. They are: Dongyingia sannionis sp. nov., Candona himalaica sp. nov. and Eucypris alpina sp. nov. Previous palaeontological data from the Basgo Formation, although embracing a number of vertebrate and invertebrate groups and also charophytes, have been rather poor and have not allowed anything other than a somewhat conjectural age determination. However, the genus Dongyingia is only known elsewhere from the Upper Oligocene of China, where it is an abundant and characteristic component of non-marine sequences. The overall excellent preservation of the Ostracoda in this study militates against their having been derived and, thus, provides good evidence for a Late Oligocene age for the Basgo Formation.

During an investigation of type collections in The Natural History Museum, London, made in India during the nineteenth century, the syntypes of Cypris subglobosa Sowerby have been re-discovered. This species is shown to belong to the genus Paracypretta and to be confined to the Upper Cretaceous, and possibly Palaeocene, non-marine intertrappean deposits of the Indian Deccan Volcanic Province. The numerous and widespread Recent and Quaternary records of this taxon are of a separate species that belongs to the genus Cypris. The examination of comparative material from a number of localities in India reveals the presence of two other contemporary species of ParacyprettaP. jonesi Bhatia and Rana and P. elizabethae sp. nov., which is formally described herein.

It has been shown that the percentage of Platycopina (the sole remaining group of filter-feeding Ostracoda since the global extinction of the Metacopina in the Lower Toarcian) making up a fossil ostracod fauna can be used as a measure of dissolved oxygen in past oceans. High levels of platycopids indicate low oxygen and vice versa. A new scale is introduced here, based mainly on the environmental oxygen levels of modern oceans and their equivalent percentages of living platycopids, in order to evaluate the palaeo-oxygen levels of the Upper Chalk in East Anglia. The effects of varying oxygen concentrations on the overall simple species diversity of the Ostracoda is also shown to have important palaeoenvironmental implications. The study is based on 79 samples from the Santonian to Lower Maastrichtian of the Trunch Borehole and 126 samples from outcrops in Suffolk and Norfolk, ranging from the Coniacian to Lower Maastrichtian. The Coniacian is shown to have been a time of low to very low oxygen, except for its upper part that was much better ventilated. The Santonian and Lower Campanian were low to very low in their dissolved oxygen, while the Upper Campanian and particularly the Lower Maastrichtian had much higher oxygen levels. Notwithstanding these general trends, oxygen levels appear to have fluctuated rapidly throughout the interval, during times of both generally low and high oxygenation. These variations in oxygenation are thought to have been associated with the Oxygen Minimum Zone and its migrations onto the continental shelf and subsequent retreat to the continental slope. This in turn is related to sea-level fluctuations and this, together with the potential for the application of this technique to sequence stratigraphy are discussed.

Study of historical collections in the Department of Palaeontology, The Natural History Museum, London (housed both in Micropalaeontology and Mollusca) has yielded further important Indian intertrappean Ostracoda. In this paper eight species are described and illustrated, one of them being new. The species are: Limnocythere sp., Cypridopsis palaichthonos Bajpai and Whatley, C. wynnei Whatley and Bajpai, C. alphospilotos sp. nov., ?Eucypris verruculosa Whatley, Bajpai and Srinivasan, Mongolianella cylindrica (Sowerby), M. hislopi (Jones) and ?Moenocypris hunteri (Jones). A lectotype is designated for Cypris (=Mongolianella) cylindrica from Sowerby's rediscovered syntypes, but although Jones's two species, Cypris (=Mongolianella) hislopi and C. (=?Moenocypris) hunteri, are also redescribed, it is not from type material which must, unfortunately, be presumed lost.

A rather impoverished fauna of only nine species of non-marine Ostracoda, belonging to seven genera was recovered from the classic intertrappean locality of Mohagaonkala (Mohgaon-Kalan), in Central India. Two species are cytherids and the remainder cyprids. Three of the species are new: Gomphocythere paucisulcata sp. nov., Cypridopsis elachistos sp. nov. and Zonocypris labyrinthicus sp. nov., while the remaining six species have been described previously from a variety of Upper Cretaceous localities in Peninsular India. Although one species Frambocythere tumiensis (Helmdach) occurs outside India, the sub-species which occurs at this locality, F. t. lakshmiae Whatley & Bajpai, is an Indian endemic. The present fauna confirms that the non-marine Ostracoda of the intertrappeans are essentially endemic to India, despite prior claims to the contrary.

The Upper Bathonian and Lower Callovian ostracod species Fastigatocythere juglandica (Jones, 1884) is shown to comprise a total of five subspecies. Of these, F. juglandica juglandica, F. juglandica major (Jones & Sherborn, 1888) and F. juglandica postrotunda subsp. nov., described as new herein, are all confined to the Upper Bathonian. Lophocythere fulgurata (Jones & Sherborn, 1888) is demonstrated to be an instar of F. juglandica major. Fastigatocythere juglandica degenerata subsp. nov., described as new herein and F. juglandica rugosa Weinholz comb. nov., both confined to the Lower Callovian, extend the known range of the species into that stage for the first time.

Fifteen key species of Recent Ostracoda (all but one from Indo-Pacific waters), selected from the collections of G. S. Brady and deposited in the Hancock Museum, Newcastle-upon-Tyne and The Natural History Museum, London, are reviewed. Holotypes and lectotypes have been formally designated and illustrated (by SEM) in the case of seven of these species: Neonesidea crosskeiana (Brady, 1866), Macrocyprina decora (Brady, 1866), Macrocyprina maculata (Brady, 1866), Pontocypris attenuata (Brady, 1868), Neocyprideis spinulosa (Brady, 1868), Keijia demissa (Brady 1868), Cytherella semitalis (Brady 1868). Other taxa reviewed and re-illustrated are five species erected by Brady in 1880: Neonesidea woodwardiana, Paranesidea globulus, Loxoconcha pumicosa, Kotaracythere inconspicua, Cletocythereis rastromarginata and Cytherelloidea venusta, and one species described by Brady in 1890: Neomonoceratina entomon. Lectotypes of these have been designated previously, elsewhere. The final species, Neocyprideis timorensis which, although found by Brady in 1880, was first formally described by Fyan in 1916.

Boomer, I., Whatley, R., Bassi, D., Fugagnoli, A., Loriga, C. (2001). An Early Jurassic oligohaline ostracod assemblage within the marine carbonate platform sequence of the Venetian Prealps, NE Italy. Palaeogeography Palaeoclimatology Palaeocology, 166(3-4), 331-344.

The limnocytherid genus Acantharhinocythere is described from the Aptian-Albian shales of the Lower Cretaceous Blairmore Group of Alberta, Canada. These sediments are of non-marine, probably mainly freshwater or slightly brackish (oligohaline) lacustrine origin and the genus occurs in a typical Canadian Prairie Province Lower Cretaceous “Wealden” type ostracod assemblage, together with species of such genera as Theriosynoecum and Cypridea Acantharhinocythere differs from other limnocytherid genera in its shape and outline, but particularly in its unique mid-anterior spinose protuberence. The possible function of this structure is discussed.

A review of the literature on the taxonomy of Triassic and Early Jurassic cytheracean Ostracoda reveals that the validity of many genera is questionable. A number of studies of the Triassic microfaunas from eastern European sequences have, in particular, obscured the true generic and suprageneric classification of many ostracod taxa. The present study concentrates on the diverse extant cytheracean family the Cytheruridae, whose origins are in the earliest Mesozoic–latest Palaeozoic, but it is clear that many contemporary cytheracean families present similar problems. This review clarifies the previous taxonomic confusion and obfuscation by demonstrating that many of these genera are spurious having been erected on specific rather than generic morphological criteria. Many of them are best accommodated within the extant genus Eucytherura Müller, 1894. Most of the cytherurid genera known from the Liassic deposits of NW Europe can be traced back to these Triassic assemblages. In considering the origin and earliest evolution of the Cytheruridae, we note that some Triassic taxa share characteristics typical of both the Cytheruridae and the Bythocytheridae and it is suggested that the former may have arisen from the latter family during the latest Permian or earliest Triassic. We also note that the palaeoenvironmental interpretation of many of the Triassic deposits is brackish-water, marginal marine.

Formerly the fourth largest inland water body in the world, the volume and area of the Aral Sea have decreased dramatically over the past 30 yr largely as a result of human actions. Throughout its approximately 2 million year history the fate of this water body has been intimately linked with that of its two main in-flowing rivers, the Amu Darya and the Syr Darya. We present a review of the hydrological, palaeontological and sedimentological evidence for the evolution of the Aral Sea based largely on Russian literature. Although the structure of the Aral Basin can be traced back to the late Neogene, the Sea has only existed in its present form for the past 8–10 ka and the Holocene history has been shaped by regional climatic variations, the development of the associated drainage system and anthropogenic forces. Past hydrological changes in the Aral Basin have led to systematic shifts in the level of the Aral Sea which are reflected sedimentologically through the deposition of `transgressive’ and `regressive’ sedimentary units and geomorphologically through the development of terraces. All the above data are integrated to produced a Late Quaternary history of this important water body.

Two additional species of nonmarine Ostracoda, both Cypridacea and of Maastrichtian age, are added to the fauna recently described by Bhandari and Colin from the intertrappean beds of the Deccan Traps at Anjar in the District of Kachchh (Kutch), Gujarat State, India. The two species are from the same locality and are Paracypretta bhatiai Khosla and Sahni , in press) and Limnocypridea ecphymatos sp. nov.

A review is undertaken of the nine species of Procytherura known to occur in Argentina and a new species, Procytherura serangodes sp. nov. is described. The global distribution of the genus indicates that it was more or less equally diverse and widely distributed in both hemispheres during most of the Lower and Middle Jurassic, but that in the Upper Jurassic and in the Lower Cretaceous, it became progressively restricted to the Southern Hemisphere. The widespread distribution of several Jurassic species of Procytherura, which occur in both Great Britain and Northwest Europe and in Argentina, is shown to be related to the availability of important migration routes, including the Tethys and the Hispanic Corridor. In the Lower Cretaceous, the very widespread distribution of Procytherura in the Southern Hemisphere, is used to support the existence of important routes along the eastern and western seaboards of Africa, the latter associated with the opening of the South Atlantic.

The composition of Jurassic marine ostracod and foraminiferal assemblages from the Neuquen Basin is analysed. The absence of these microfossils from certain levels is attributed to a number of causes, such as inimical facies for their existence or for their preservation. Evidence is produced demonstrating that the absence of ostracods and the virtual absence of Foraminifera from such important Middle Jurassic sections as that at Chacay Melehue is due to their lower bathyal or abyssal palaeodepth. The relative success of filter and deposit feeders is shown to be probably related to palaeoxygen levels, with filter feeders being able to tolerate lower levels of oxygen concentration than their competitors. The palaeoecology of the various ostracod assemblages is compared and contrasted with that of their contemporary Foraminifera. While in the Liassic and the early Middle Jurassic there is a considerable general similarity between ostracod assemblages wordwide, throughout the remainder of the Jurassic there is evidence of the progressive isolation of southern South America, with consequent generic impoverishment and the absence or extreme rarity of many of the major families and genera of NW Europe. Conversely, there are no genera or supra-generic taxa endemic to Argentina.

The distribution of Ostracoda in three long cores from the deep eastern Arctic Ocean was studied to determine the palaeoceanographical history of the Eurasian Basin during the late Quaternary. The samples for this study were obtained from the Lomonosov Ridge, Morris Jesup Rise and Yermak Plateau during the Arctic 91 expedition. Ostracoda previously studied in coretops at the same sites as the present study have shown that individual species have a strong association with different water masses and bathymetry. Throughout the late Quaternary, cores exhibit ostracod-rich layers separated by barren intervals. On the basis of biostratigraphical, isotopic and palaeomagnetic data the fossiliferous levels are interpreted as representing interglacial stages. The twenty most significant species were selected for subsequent quantitative investigation using Cluster and Factor analyses, in order to determine similarity and variance between the assemblages. An additional statistical method employing Modern Analogues and the Squared Chord Distance dissimilarity coefficient was utilised to compare the present late Quaternary fossil samples with a modern Arctic database. The results reveal a major faunal division within the Arctic Ocean Deep Water (AODW). Highly abundant and diverse assemblages within the cores were found to group and have good analogues with the Recent bathyal depth (1000–2500 m) upper AODW assemblages. Conversely, assemblages with low abundance and diversity correlate well with abyssal depth (>3000 m) lower AODW assemblages. The palaeoceanographical history is complicated by the influence of adjacent water masses such as Canada Basin Deep Water (CBDW), Greenland Sea Deep Water (GSDW) and most importantly, Arctic Intermediate Water (AIW), which all had an influence on the ostracod assemblages during the late Quaternary. An enhanced flow of warm saline AIW into the Eurasian Basin results in species-rich upper AODW assemblages having good analogues down to 2750 m in the water column. In contrast, lower AODW assemblages influenced by cold well-oxygenated GSDW give analogues at depths as shallow as 1000 m. The faunal changes are the consequence of rapid climatic fluctuations in the eastern Arctic Ocean during the late Quaternary that are intrinsically linked to palaeoceanographical alternations in warm and cold current inflow from adjacent basins.

From a total of 20 samples, of which 8 were collected in the eulittoral and 12 by SCUBA diving in the sublittoral, more than 11,000 ostracods were recovered. These comprise 30 species belonging to 20 genera. Of the 30 species, one is a cladocopid, one a platycopid and the remainder podocopids, of which three are bairdiids, three cyprids and the remainder (22) are cytherids. Twenty-one of the species are both new and endemic as are two new subspecies. Only four species have been described from elsewhere (Peripontocypris magnafurcata, Neonesidea tenera, Triebelina bradyi, Dentibythere dentata), although two others (Cytherelloidea keiji, and Loxoconchella honoluluensis) are represented at the island by new subspecies. However, an additional three species are known elsewhere only in manuscript; two of these are only known from the nearest inhabited land, the Pitcairn/Henderson group some 1400 miles to the west. The remaining 22 are endemic to Easter Island and are monographed elsewhere. There are no species common with the Galapagos Islands nor with the South or Central American coast or Clipperton Island. The three described species and the four known, but as yet undescribed species, all occur to the west and it is in the Indo-Pacific and Australasia that the closest relatives of the endemic species are encountered. The Easter Island fauna seems clearly to be the product of a migration or series of migrations from the west. However, that this or these events were not simple is attested to by the fact that, although the seven species known at Easter Island and elsewhere are all from tropical environments, none of the pan-tropical Tethyan taxa are recorded there. Three of this group occur at Pitcairn/Henderson, however, although none are among the four species common to Pitcairn/Henderson and Easter islands. Easter Island and the other volcanic islands to the west and west-northwest are all situated on a submarine ridge together with numerous guyots. Many of these today have relatively shallow summits and all flat-topped seamounts must have been emergent at times in their history. It is suggested that the eastwards migration (migrations) took place at those times of lowest sea level and greatest emergence of the summits by normal island-hopping sweepstakes routes.

Results are presented from a preliminary analysis of late Pleistocene ostracod bearing samples from a lacustrine section collected in the Maquinchao valley in the Cari-Laufquen Lake region (lat. 41°35′S; long. 69°25′W) situated 150 km east of San Carlos de Bariloche on the northern Patagonian steppe. The rich lacustrine ostracod fauna, obtained during the Lagos-Comahue project, has yielded important climatic and environmental information on the late Pleistocene and Holocene of northern Patagonia. The fauna comprised mainly new species of Limnocythere and Eucypris. During the last 13,200 years B.P. (thermoluminescence dating), levels representative of much more humid conditions than those obtained at the present time, are suggested by stratigraphical levels which include those yielding a very abundant fauna of Eucypris fontana (Graf) and Limnocythere rionegroensis Cusminsky and Whatley. These humid climatic levels are overlain by a sequence in which the ostracod faunal abundance decreases very abruptly and this event coincides with the appearance of evaporites suggesting the onset of significantly drier conditions during the Holocene.

The ostracod genus Krithe is reported from four grab, two box-core, 62 coretop samples, and Neogene to Quaternary DSDP cores from the abyssal and bathyal regions of the Tasman Sea and off southern Australia. Species identification followed the taxonomic system proposed by Coles et al. (1994), in which the anterodorsal radial pore canals are of fundamental importance. A total of 19 species are recognised, five species are described as new: K. comma, K. dilata, K. pseudocomma, K. prolata , and K. triangularis. Fifteen species are referred to previously described species, and the remaining rare species are left in open nomenclature. Although no living specimens have been recovered, shells of all species have been found in modern sediments and are, therefore, considered to be extant. Overall, the stratigraphic distribution of the species demonstrates an increase in diversity from 3 to 19 species since the Early Miocene, with no extinction. The bathymetric range of most species is wide, though in certain species there are significant differences between the two study regions, such as on the Australian Continental Slope, the relatively much deeper occurrences of K. triangularis and K. marialuisae, and the absence of K. dolichodeira a species found commonly elsewhere. An explanation for such differences is most likely to relate to nutrient, substrate, and oceanographic differences between the two regions.

A study of the family Cytheruridae in Recent sediments from the coast of northern Rio de Janeiro State revealed the presence of four new species: (Hemicytherura auriculata, Oculocytheropteron delicatum, Oculocytheropteron circumcostatum and Semicytherura caudata,) and four previously described species (Semicytherura rugosoreticulata Whatley, Chadwick, Coxill & Toy, 1988, Oculocytheropteron macropunctatum Whatley, Chadwick, Coxill & Toy, 1988, Oculocytheropteron reticulopunctatum Whatley, Chadwick, Coxill & Toy, 1988 and Paracytheridea bulbosa Purper & Ornellas, 1989). A further two species Cytheropteron sp. and Kangarina sp. are left in open nomenclature due to paucity of the material. The ecology and distribution of the fauna suggest that the presence of many of these species, which also occur in colder waters off the coast of Uruguay and Argentina, is probably due to the upwelling of the South Atlantic Central Water in this area.

No less than seven junior synonyms exist of Theriosynoecum kirtlingtonense Bate, 1965 . This taxonomic confusion has been brought about by variations in the degree and patterns of noding within a single species, which was widespread both geographically — from the south of England to the Hebrides — and in the palaeoenvironments it occupied — from freshwater to polyhaline. A critical analysis is undertaken of the taxonomy of Theriosynoecum kirtlingtonense within a framework of palaeoenvironmental constraint, using only those bio-characters which are invariable at the intraspecific level. The distribution of the species in a section of the upper Bathonian Forest Marble Formation at Tarlton in Gloucestershire, is investigated. The population age structure was used to determine those levels in which the species occurs as an autochthonous component, and its variable noding investigated with respect to salinity variations. All aspects of noding in this limnocytherid and in the Neogene to Recent brackish water species Cyprideis torosa (Jones, 1850) are compared and contrasted and both are shown to be related fundamentally to salinity.

From 16 sediment samples collected from the Chilean part of the Strait of Magellan, 2338 Ostracoda were recovered. These represent 61 species belonging to 45 genera and 16 families. Previous work in the Tierra del Fuego Province has shown the faunas to be highly endemic, resulting from the relative isolation of the region and its particular climatic and oceanographical characteristics. The fauna of the Strait of Magellan is similar to those previously described with one notable exception: the occurrence of deep-water, psychrospheric species at shallow depths. Species of Bradleya, Agrenocythere, Poseidonamicus, Bythoceratina, and Legitimocythere, usually recorded from bathyal to abyssal depths of more than 1000 m, were found together in the same samples with a typical, shelf fauna. Such unusual depth distribution of psychrospheric species may have resulted from the extremely cold temperature and low salinity of the water in the southern Strait of Magellan, coupled with the upwelling of cold, deep water masses.

Twenty one species of the genera Muellerina and Thaerocythere are considered. Of these, 11 species, including the type species of both genera, have been described previously. Two species are left in open nomenclature due to inadequate numbers but eight are described as new. These species are: Muellerina latimarginata (Speyer, 1863), M. abyssicola (Sars, 1866), M. lacunosa (Jones, 1857), M. praeabyssicola Uffenorde, 1981, M. parvipunctata Uffenorde, 1981, Thaerocythere crenulata (Sars, 1866), T. hoptonensis (Brady, Crosskey & Robertson, 1874), T. mayburyae Cronin, 1991, T. oedichilus (Brady, 1878), T. trachypora (Jones, 1857), T. trapezia (Brady, 1878), and the new species M. dolabrata, M. metabyssicola, M. orygyma, M. pliocenica, T. biformis, T. praecrenulata, T. vermiculata, T. woutersi and T. wittei. The phyletic relationships of these northwestern European species are considered.

Ponticocythereis species are a discrete phylogenetic group within the Trachyleberididae that evolved in the SW Pacific and Australasian regions during the Tertiary. The presence of similar scale-like spines on the unrelated species Ponticocythereis manis Whatley & Titterton, 1981 and Trachyleberis floridus sp. nov. is presented as an example of convergent evolution.

The discovery of some exceptional non-marine fossil Ostracoda, showing larval stages within the carapaces of females, demonstrates that incubation was an ontogenetical adaptation which appeared at least as early as the Permian. Thus, it seems, the superfamilies Danvinulacea and Cytheracea diversified in Permian lakes where the Carbonitacea had flourished in the Carboniferous. The Cypridacea accomplished an evolutionary radiation in continental environments after a permanent invasion from the sea in the Middle Jurassic, thanks to the resistance of their eggs to dessication and heezing and the evolution of parthenogenetic reproduction.