Search results for "Ostracoda"
showing 7 items of 17 documents
The recent non-marine ostracods of tunisia: An updated checklist with remarks on their regional distribution patterns and ecological preferences
2020
Different lines of investigation have recently contributed to increasing the available knowledge about the invertebrates inhabiting inland waters of north Africa, but a comprehensive synopsis on Tunisian Ostracoda is missing to date. An updated checklist of Recent non-marine ostracods from Tunisia and data on their distribution is thus offered here, representing the most extensive survey on this crustacean group ever carried out in inland waters throughout the country. One-hundred-five sites covering various climate zones, from Mediterranean to desert areas, were sampled between 2002 and 2012. Most of the considered water bodies were temporary or ephemeral habitats, but a few permanent site…
Heterocypris bosniaca (Petkowski et al., 2000) : ecología y ontogenia de un ostrácodo (Crustacea: Ostracoda) de pozas temporales
2014
Los ostrácodos son un grupo de pequeños crustáceos con amplia distribución mundial, cuyo cuerpo está protegido por dos valvas laterales que suelen preservarse con facilidad en el sedimento. En el presente trabajo se muestra la primera cita del ostrácodo Heterocypris bosniaca Petkowski, Scharf y Keyser, 2000 para la Península Ibérica. Se trata de una especie de cipridoideo muy poco conocida que habita pozas de aguas temporales. Se descubrió el año 2000 en Bosnia y desde entonces solo se ha reportado su presencia en Israel (2004) y en Valencia (presente trabajo). En primer lugar se lleva a cabo una descripción del área de estudio. Tras conocer varias pozas con la presencia de la especie se re…
Population dynamics and tolerance to desiccation in a crustacean ostracod adapted to life in small ephemeral water bodies
2011
AbstractGiven their small size, isolation and unpredictability, temporary rockpools present high environmental stress and impoverished communities of species that have adapted to such stressful conditions. Special adaptations of the invertebrates living in these habitats include tolerance to desiccation and fast ontogenetic development in order to maintain stable populations and face high risk of extinction. Dozens of small rockpools (mostly with Ø<1m) can be found in east Spain on limestone substrate, where the only known Iberian populations of Heterocypris bosniaca Petkovski et al. (2000), an ostracod species with geographic parthenogenesis, have been recently found. In this survey, two o…
Revision of Recent and fossil Mixtacandona Klie 1938 (Ostracoda, Candonidae) from Italy, with description of a new species
2017
Although studies on ostracods dwelling in inland subterranean habitats of Italy have increased in the last decades, highlighting a considerable taxonomic diversity, available information is still far from sufficient to understand phylogenetic and biogeographic relationships. Mixtacandona Klie 1938 is one of the most common and diverse genera of ostracods in subterranean waters. Of the 20 living recognized species in the genus, all stygobiontic and restricted to the Palearctic Region, four are known for the Italian peninsula and Sardinia, one of which exclusively as fossil. Several other Recent and fossil taxa attributable to Mixtacandona, but identified at supraspecific level, have been rep…
Ecologia de comunitats d´invertebrats aquàtics de la Península Ibèrica, amb especial rellevància als Ostracoda
2015
L’ecologia dels invertebrats d’aigües continentals pot abordar-se mitjançant distints enfocaments. En aquesta tesi, que presenta dos parts diferenciades, incidim inicialment en el paper que juga la interrelació de comunitats planctòniques i bentòniques amb el medi, que en comunitats somes (com moltes de les estudiades) es troben habitualment mesclades a la columna d’aigua. En un primer treball es va estudiar com varien estacionalment les comunitats d’invertebrats aquàtics de dos llacunes de muntanya properes (4,5 km) amb climatologia similar però distint hidroperiode (Llacuna de Bezas, semi-permanent i Llacuna de Rubiales, una bassa temporal, ambdues a Terol). A Bezas s’observà un canvi en …
Pyriproxyfen, a juvenoid hormone analog, does not induce male production in parthenogenetic lineages of Eucypris virens (Crustacea: Ostracoda)
2007
Analogs of juvenoid hormones are increasingly recommended for controlling insect pests in agriculture. One of these analogs, pyriproxyfen, was found to be very potent in inducing male production in Daphnia under laboratory conditions, even after acute exposure. Other studies also demonstrated a major role of juvenoid hormones for the sex determination in arthropods that have sex chromosomes. We exposed parthenogenetic lineages of the freshwater ostracod Eucypris virens to a wide range of pyriproxyfen concentrations, and compared mortality and fecundity between treated and control animals. Animals exposed to the highest concentrations of pyriproxyfen (3-30 nM) experienced a higher mortality …
Mecanismes estructuradors de les metacomunitats d'ostracodes d'aigües continentals
2016
Un dels objectius principals de l'estudi de les metacomunitats és entendre els patrons de distribució de grups d'espècies i els mecanismes ecològics que condicionen aquestos patrons. Recentment, els estudis sobre metacomunitats han estat centrats en determinar la importància relativa de l'ordenació d'espècies (i.e. l'efecte filtrador de l'ambient) i la dispersió (i.e. els efectes espacials) com a mecanismes estructuradors de les metacomunitats. En aquesta tesi hem analitzat el paper d'aquestos mecanismes estructuradors sobre diferents metacomunitats d'ostracodes i altres invertebrats en tres sistemes aquàtics diferents situats a l'est de la Península Ibèrica: llacunes temporals, basses de r…