Claude Meisch

Distribution patterns of freshwater Ostracoda (Crustacea) in the Canary Islands with regards to habitat use and biogeography

In this study biogeographic patterns and habitatrelationships of freshwater Ostracoda wereinvestigated in the Canary Island archipelago. Mostdata were collected from published studies, thoughalso new data from Gran Canaria are presented. In all,22 freshwater species are presently known to theCanaries. Six species, viz. Ilyocypris bradyi,Cypris bispinosa, C. pubera, Herpetocypris chevreuxi, Heterocyprisincongruens, and Sarscypridopsis lanzarotensisare new to Gran Canaria, the first two also being newto the Canaries in general. Testing the influence ofa number of variables on faunal richness indicatedonly a weak association with island area. Distancesbetween islands also proved not significant, and sodid other properties of islands, including age,altitude and precipitation. This was in contrast to acomparison set of data comprising aquatic beetles.Like beetles, however, ostracods did not show a nestedpattern, i.e. faunas of species-poor islands were notsubsets of species-rich island faunas. By having lowendemicity (endemic species lacking in the Canaries),the ostracod fauna resembled island fern floras. Bothgroups of organisms have tiny diaspores (diameter<0.1 mm) and are extensively parthenogeneticsuggesting similar dispersal and founder mechanisms.We identified a pattern (with one exception), wherethose species with distributions extending acrossseveral islands also had wider within-islanddistributions. Many species showed affinities todifferent habitats depending on conductivity of water,altitude and habitat types: whether they werepermanent or temporary, hypogean or epigean, orcharacterized by running or stagnant waters.

On the origin of the putative furca of the Ostracoda (Crustacea)

The posterior end of body of the extant ostracods exhibits a pair of variously shaped appendages, commonly designated as furca(e), uropods or caudal rami, used for feeding and/or locomotion. It is here shown that the socalled furca of all extant ostracods has evolved from the (probably epipodal) vibratory plates of a pair of uropods.

The ostracod fauna of Mamilla Pool (Jerusalem, Israel) (Crustacea, Ostracoda)

Abstract The ostracod fauna of Mamilla Pool (Jerusalem, Israel) is described and the pool itself characterized. Nine species are found, two of which are new to the fauna of Israel, Not less than four Eucypridinid species and genera co-occur and some new soft part features are illustrated for these taxa. The genus Eucyprinotus Sywula is here retained as valid and is transferred to the Eucypridini. A discussion on the taxonomy of the West Palaearctic Eucypridini and a key to the five genera is given. After re-examination of the type-material, Cypris orientalis Baird, 1859, orginally described from Mamilla Pool, appears to be a synonym of the widely known Potamocypris arcuata (Sars). Not all species appear and disappear simultanously during the annual cycle of the pool. E. virens and T. lutaria are the First, E, rostratus and T. clavata are the last to appear. In the final (senile) stage of the annual cycle of the pool, only the Cypridopsines and the Ilyocypris appear to survive.

Thermopsis thermophila n. gen. n. sp. from hot springs in Nevada, U.S.A. (Crustacea, Ostracoda)

Thermopsis thermophila n. gen. n. sp., a new freshwater ostracod species is described from hot springs in Nevada, U.S.A. The animals were collected within a temperature range of 40–55 °C. The new genus belongs to the Ostracoda Podocopida Cypridoidea Cyprididae Cypridopsinae.

Redefinition of the genus Typhlocypris Vejdovský, 1882 (Ostracoda, Candonidae)

The taxonomy of the genus Typhlocypris Vejdovský, 1882 is reviewed. New morphological information on Typhlocypris eremita (Vejdovský, 1882), the type species of the genus, is provided, and a new reference material is presented. The generic diagnosis is emended with details derived from the developmental trajectory of the valves, from the juvenile stage A-3 to the adult. Those criteria clearly differentiate Typhlocypris from the related genus Pseudocandona Kaufmann, 1900. As here redefined, Typhlocypris is a phylogentic lineage of the subfamily Candoninae containing extant species presently living in aquatic subterranean habitats and fossil species recovered from non-marine Late Palaeogene to Neogene and Quaternary deposits in Europe and western Asia. The type species of Typhlocypris is considered a metaspecies, taxonomically treated as T. eremita (sensu lato), which includes populations resembling the newly designated reference material. The homeomorphic triangular valve shape of the Candoninae is discussed. Careful examination of the valve morphology of Typhlocypris combined with the analysis of limb traits helps to distinguish representatives of this genus from unrelated phylogenetic groups presenting similar triangularly shaped valves. It is emphasised that for a useful description of Typhlocypris taxa both transmitted light and scanning electron microscopy are necessary.

On Paranacypris samambaiensis gen. nov., sp. nov. (Crustacea, Ostracoda), the first South American psychrodromid from the alluvial valley of the Upper Paraná River, Brazil

Paranacypris samambaiensis gen. nov., sp. nov. is here described from closed lakes in the alluvial valley of the Upper Paraná River. The new genus, characterized by a large frontally overlapping left valve, belongs in the Psychrodromini, and is the first representative of this tribe described in South America. Nevertheless, it has some different character states, and the diagnosis of the tribe had to be adapted. The species is rare and restricted to closed lakes (not in contact with the main channels of the river). It mostly occurs in benthic littoral habitats, and far less in the pleuston communities, the most common habitat in this floodplain. The behaviour of P. samambaiensis gen. nov., sp. nov. is enigmatic because it combines long natatory setae on the antennae (swimming behaviour) with a very stout caudal ramus, including the spine‐like posterior seta (crawling behaviour). We present a key to the genera of the Herpetocypridinae.

Description of the male of Potamocypris villosa (Jurine, 1820) (Crustacea, Ostracoda)

A bisexual population of Potamocypris villosa, found in Lago de Encina, a mesotrophic lake in the Cantabrian mountains, NW Spain, is the first certain record of the male of this species. Valves and soft parts are described. Males of Potamocypris-species lack a furca although a rudimentary furca is always present in females. The same applies to species of related genera, such as Tanganyikacypridopsis and Plesiocypridopsis. Some remarks on the position of the genus Potamocypris in the Cyprinopsinae are presented.

An updated checklist of the Recent non-marine Ostracoda (Crustacea) of Iran, with a redescription of Eucypris mareotica (Fischer, 1855)

An updated checklist of the extant non-marine Ostracoda of Iran, with 74 species in all, is presented, based on literature and new collections made in May 2011. The occurrence of 19 non-marine ostracod species recovered from 10 localities in May 21-26, 2011 is reported together with ecological data. Eucypris kerkyrensis Stephanides, 1937, Ilyocypris inermis Kaufmann, 1900, Psychrodromus fontinalis Wolf, 1920, and P. olivaceus (Brady & Norman, 1889) are new to the fauna of Iran. Eucypris mareotica (Fischer, 1855) is redescribed and its taxonomic position is discussed. It is shown that E. mareotica-synonymous with E. inflata-does not belong to the genus Eucypris sensu stricto, and even not to the subfamily Eucypridinae; as its characters do not fit any available genus, the species is therefore provisionally left in the genus Eucypris at present. Eucypris mongolica (Daday, 1909) is proposed to be considered an infraspecific variety of E. mareotica. The following new combination is here proposed: Strandesia ambigua (Ghetti, 1972) nov. comb.