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1.
Zootaxa ; 4801(2): zootaxa.4801.2.11, 2020 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-33056666

RESUMO

I present taxonomical re-descriptions of two Indian spinicaudatan species deposited at the Smithsonian National Museum of Natural History, USA, emphasizing on a few characters not highlighted in the original descriptions. Specimens collected from South India and deposited in the museum forty years ago were assessed and re-described. The study shows that the Cyzicidae species deposited as Caenestheriella sp. is Ozestheria indica while the Eulimnadia species is the widely distributed Eulimnadia michaeli. Many of the taxonomical characters were variable and did not exactly match the earlier description for both the species. Ozestheria indica could be distinguished from other valid Indian species on the telson characters and its occurrence proximity to the type locality of the species. This species is currently restricted to Peninsular India. Eulimnadia michaeli could be identified based on its characteristic egg surface morphology, though, the inner layers of the egg did vary when compared with the western Indian population. Using museum material, the validated species tally of Indian spiny clam shrimps now stands at 8 while 15 still await re-examination.


Assuntos
Bivalves , Animais , Crustáceos , Museus
2.
Zootaxa ; 4763(1): zootaxa.4763.1.2, 2020 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-33056876

RESUMO

A compilation of the ciliated species found on freshwater and marine ostracods as epibiont or parasite (endobiont) has been carried out based on published records. The checklist includes the taxonomic position of each species of epibiontic and endobiontic ciliate, the species of basibiont ostracodes, the geographic zones and the bibliographic references where they were recorded. Altogether 7 suctorian, 29 peritrich, one apostome and one scuticociliatid species were listed. Two of recorded suctorian species are possible specific to marine ostracodes, whereas only one, Tokophrya sibirica to freshwater hosts. Fourteen species of peritrichs are likely specific to freshwater ostracodes, while three possible specific to marine ostracode hosts. Other suctorian and peritrich ciliate species were found on a variety of host taxa. One species of scuticociliatid was recorded as endobiont in ostracod.


Assuntos
Cilióforos , Animais , Crustáceos , Água Doce , Registros
3.
Zootaxa ; 4786(4): zootaxa.4786.4.3, 2020 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-33056460

RESUMO

Stenocypris major major (Baird, 1859) and Stenocypris major sketi Petkovski Meisch, 1996 were encountered in the Eastern part of Thailand. These two taxa are thus re-described based on Thai materials. The taxonomic position of S. major sketi is revised and placed as a separated species due to the distinct features in the valves and the soft parts morphology, especially in the presence of the postero-dorsal expansion on both valves, the different patterns of the posterior inner lamella margins and the caudal ramus morphology. Therefore, S. sketi Petkovski Meisch, 1996 is erected for S. major sketi. The occurrence of S. sketi in the present contribution is the first report in Thailand and Southeast Asia. This taxon is thus far endemic to the Oriental region. The selected diagnostic characters of the genus Stenocypris are also briefly discussed.


Assuntos
Crustáceos , Distribuição Animal , Animais
4.
Zootaxa ; 4851(1): zootaxa.4851.1.8, 2020 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-33056743

RESUMO

Representatives of the Class Ostracoda are widely used as tools in applied paleoecological and biostratigraphical studies in all continents. In the Araripe Basin, located in the northeastern of Brazil, the Romualdo Formation is one of the most studied, not only for the preservation but also for the abundance of its fossils. The ostracod genus Pattersoncypris Bate, 1972 is well-represented in this formation and it is the most abundant, which reinforces the importance of its taxonomic study. In this work, Pattersoncypris minima sp. nov. is described for the Romualdo Formation as a contribution to the knowledge on Brazilian Cretaceous non-marine ostracods. Taphonomic aspects are also presented, considering the complete ontogenetic stages of the material.


Assuntos
Crustáceos , Fósseis , Animais , Brasil
5.
Zootaxa ; 4759(1): zootaxa.4759.1.8, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33056936

RESUMO

The genus Cypris, considered the oldest ostracod generic name erected using the Linnean system, comprises a reduced number of large-bodied species, mostly found in Africa and Asia. Only six of them are known to occur in Europe. Here we describe a new species, Cypris pretusi sp. nov., collected in small temporary streams and ponds along the Eastern Iberian Peninsula and Minorca (Balearic Islands). The new species is very close to the type species of the genus, Cypris pubera O.F. Müller, 1776, but differs from it in having a set of smaller subequal spines on the posterior edge of the valves, by the absence of conspicuous spines along the front edge, and by the beak-like frontal shape of its carapace in dorsal view, similar to Cypris decaryi Gauthier, 1933. Soft parts are very similar to the type species, but it differs in having shorter swimming setae on the second antennae. Molecular analyses of the COX1 region support its status as a species distinct from C. pubera and closer to Cypris bispinosa Lucas, 1849, also providing evidence for a separation of C. pubera s.l. in two clades, one of which is here considered to correspond to Cypris triaculeata Daday, 1892. We discuss the relationships of C. pretusi sp. nov. to other members of the genus and its possible origin from nearby biogeographic regions (probably Africa or Asia) and provide a key to species of Cypris found in Europe. We also discuss the relationship between Monoculus concha pedata (= M. conchaceus), the first ostracod named by Linnæus, and Cypris pubera, the type species of the genus, described by Müller in 1776 and considered by him the same species as the one first named by Linnæus.


Assuntos
Crustáceos , Animais , Europa (Continente) , Masculino , Espanha
6.
Zootaxa ; 4809(2): zootaxa.4809.2.3, 2020 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-33055936

RESUMO

Captain Edward Belcher was instructed by the Lords of the Admiralty to conduct a Surveying Expedition of the various coasts and islands in the Eastern Seas using H.M.S. Samarang. During this voyage from 1843-1846, Assistant-Surgeon Arthur Adams, made a significant contribution to the collection of natural history specimens, and together with fellow officers J. Richards and W. Browne, he prepared numerous drawings used by Belcher to illustrate the Narrative of the voyage. Later, Adams collaborated with Adam White (an Assistant in the Zoological Branch of the British Museum) to describe the Samarang Crustacea, published jointly with Lovell Reeve on the Samarang Mollusca, edited the Zoology of the voyage of H.M.S. Samarang and was the author of Notes from a Journal of the Natural History which was published in the Narrative of the voyage by Belcher. In his Natural History, Adams provided detailed accounts on some of the crustaceans collected with formal descriptions of species new to science thereby making these names available. The history, nomenclature and validity of the crustacean species cited in this work is discussed and a list of the available names is tabulated.


Assuntos
Decápodes , Expedições , Animais , Crustáceos , Masculino , História Natural , Zoologia
7.
Zootaxa ; 4767(2): zootaxa.4767.2.1, 2020 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-33056562

RESUMO

In this study, 24 non-marine ostracod species were found in 142 samples collected from diverse water bodies from Hainan Island, south China. Among them, a new species Pseudocypretta lineata n. sp. is described and illustrated. Twelve species are new records for China. Among them, six species are identified: Microdarwinula zimmeri (Menzel, 1916), Pseudocypretta lineata n. sp., Pseudostrandesia mamarilorum (Victor Fernando, 1981c), Stenocypris malayica Victor Fernando, 1981b, Stenocypris orientalis Victor Fernando, 1981b and Strandesia freyi Victor Fernando, 1981c. Six species are left in open nomenclature: Batucypretta sp., Candonopsis? sp., Cypridoidea gen. et sp. indet. 1, Cypridoidea gen. et sp. indet. 2, Cyprinotus cf. kimberleyensis McKenzie, 1966 and Vestalenula sp. Additionally, a re-description of Strandesia freyi is provided.


Assuntos
Crustáceos , Animais , China , Água Doce , Ilhas
8.
Zootaxa ; 4768(2): zootaxa.4768.2.4, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33056524

RESUMO

An annotated checklist of the mantis shrimps (Stomatopoda) occurring in India is compiled from published literature and specimens collected from coastal areas of Gujarat state. A total of 72 species, 35 genera, 10 families and 5 superfamilies reported from Indian waters are listed. Four species were recorded for the first time from Gujarat while one species, Erugosquilla hesperia (Manning, 1968), is confirmed for the first time from India. The maximum number of species was reported from Tamil Nadu (48 species), while fewest species were reported from Karnataka (2 species). The results also suggest that the east coast is more diverse (66 species) than the west coast of India (32 species).


Assuntos
Crustáceos , Mantódeos , Animais , Índia
9.
Zootaxa ; 4860(2): zootaxa.4860.2.1, 2020 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-33056160

RESUMO

Four new species or morphospecies of tanaidaceans, all of small size (c. 1 mm), from the Rangitâhua-Kermadecs component of the Southwest Pacific Expedition 2017 survey are recorded and described: Collettea coralensis n. sp., leptocheliid sp.RK#1, Psalidichelia concinna n. g. n. sp., and Stachyops cf. sebparri. Six had been described or recorded from the earlier Kermadec Biodiscovery Expedition 2011: Aparatanais tetradonta, Chondrochelia acrolophus, Metatanais progenitor, Paradoxapseudes floppae, Tanais sp., and Zeuxo kermadecensis. This brings the number of known tanaid species from the Rangitâhua/Kermadecs group to ten. The records of the Collettea species are notable for the shallow depths from which they were collected, 4-18 m, and the habitats sampled: coral rubble, coral encrusts on rocks, and red algae.


Assuntos
Antozoários , Crustáceos , Animais , Ecossistema , Expedições , Ilhas
10.
Zootaxa ; 4852(3): zootaxa.4852.3.10, 2020 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-33056420

RESUMO

The spinicaudatan family Cyzicidae represents a group of morphologically variable species whose taxonomy is still being updated (Schwentner et al. 2009, 2015, 2020; Rogers et al. 2017). There are 21 species of spinicaudatans currently reported from the Indian subcontinent out of which 4 species represent the Cyzicidae family (sensu Rogers Padhye, 2015; not considering the species from Eocyzicus genus which are now shifted to Eocyzicidae family sensu Schwentner et al. 2020). Ozestheria indica (Daday, 1913), one of the four species, has been re-described very recently (Padhye, 2020). Ozestheria indica and Ozestheria annandalei (Daday, 1913) are the two valid species currently known from peninsular India (Padhye, 2020; Rogers, 2020 2020). Padhye et al., (2015) re-described the female of a Cyzicus sp. which was later confirmed as C. annandalei (Rogers Padhye, 2015).


Assuntos
Crustáceos , Animais , Feminino , Índia
11.
Zootaxa ; 4852(2): zootaxa.4852.2.10, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-33056430

RESUMO

The spinicaudatan family Cyzicidae represents a group of morphologically variable species whose taxonomy is still being updated (Schwentner et al. 2009, 2015, 2020; Rogers et al. 2017). There are 21 species of spinicaudatans currently reported from the Indian subcontinent out of which 4 species represent the Cyzicidae family (sensu Rogers Padhye, 2015; not considering the species from Eocyzicus genus which are now shifted to Eocyzicidae family sensu Schwentner et al. 2020). Ozestheria indica (Daday, 1913), one of the four species, has been re-described very recently (Padhye, 2020). Ozestheria indica and Ozestheria annandalei (Daday, 1913) are the two valid species currently known from peninsular India (Padhye, 2020; Rogers, 2020). Padhye et al., (2015) re-described the female of a Cyzicus sp. which was later confirmed as C. annandalei (Rogers Padhye, 2015).


Assuntos
Crustáceos , Animais , Feminino , Índia
12.
Zootaxa ; 4795(1): zootaxa.4795.1.1, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-33056692

RESUMO

Rice is the staple food crop for approximately half the world's population, but some common and abundant taxa inhabiting rice fields, such as ostracods, are poorly studied. For many ostracod species only brief, initial descriptions are available, hindering reliable identifications, and so their ecological roles in rice fields remain obscure. This study partially addresses this problem by assessing the taxonomic validity of six species of Cyprinotinae ostracods reported from rice fields in Japan and South Korea: Cyprinotus  uenoi Brehm, 1936, Hemicypris megalops Sars, 1903, Hemicypris ovata Sars, 1903, Hemicypris vulgaris Okubo, 1990, Heterocypris rotundata (Bronstein, 1928), and Hemicypris kawagaensis Okubo, 2004 nomen nudum. Type material of C. uenoi was not designated and Brehm's ostracod collection is missing, but Japanese and Korean records of C. uenoi differ significantly from Brehm's original description. The Japanese and Korean species is described and named herein as Cyprinotus cassidula sp. nov. Japanese specimens reported to be Hemicypris megalops are probably misidentified, but details of the carapace of Hemicypris megalops are obscure due to poor preservation of type material. Examination of topotype material of Hemicypris posterotruncata Bate, 1970, a sub-fossil from near Lake Turkana in Kenya, demonstrates that this species is extant in Asian rice fields. Investigation of type material of Hemicypris kliei (Lindroth, 1953) has revealed that it is not a senior synonym of Hemicypris posterotruncata, contrary to previous studies. Size and morphological data indicates that Hemicypris vulgaris is a large form of Hemicypris posterotruncata and the two species are treated as synonyms herein. Examination of paralectotypes of Hemicypris ovata indicates that it is very similar to Hemicypris posterotruncata, especially the larger morphotypes, but as these two species can be distinguished by morphological features they are both retained as separate species. However, Japanese records of Hemicypris ovata are considered misidentifications of the larger forms of Hemicypris posterotruncata. Hemicypris kawagaensis, which has only been reported once from East Asia, is herein regarded as a junior synonym of Hemicypris barbadensis Broodbakker, 1983, and is likely an alien species in Asia. Asian specimens previously identified as Heterocypris rotundata show sufficient differences to European specimens to determine that they are not conspecific. This species is described as Heterocypris savatenalintonae sp. nov. Taxonomic descriptions of Hemicypris ovata, Hemicypris posterotruncata, Hemicypris megalops, Hemicypris kliei, Heterocypris savatenalintonae sp. nov., and Cyprinotus cassidula sp. nov. are presented. Finally, it is noted that past redescriptions of Cyprinotus cingalensis Brady, 1886, the type species of the genus and the subfamily Cyprinotinae Bronstein 1947, are based partly on other species.


Assuntos
Crustáceos , Animais , Japão , República da Coreia
13.
Zootaxa ; 4760(1): zootaxa.4760.1.1, 2020 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33056888

RESUMO

The present paper is a contribution to the taxonomy of the genus Strandesia. Here, we describe three new species: S. thomazi nov. sp., S. galeati nov. sp. and S. nakatanii nov. sp. We also describe the male of Strandesia obtusata (Sars, 1901); this is the first record of sexual populations of a Brazilian Strandesia species. Nine other Strandesia species from the Amazon, Araguaia, Pantanal and Paraná river floodplains are redescribed. We also propose that Strandesia trichosa Roessler, 1990 is a synonym of Strandesia psittacea Sars, 1901. Most of the species analyzed here are endemic to the Neotropical region, with the exception of Strandesia bicuspis (Claus, 1892) G.W. Müller, which occurs also (as an alien invasive species) in the Palaearctic. This genus occurs in water bodies with a wide range of abiotic variables and in many different aquatic macrophyte species. The species analyzed here have a highly conservative soft part morphology, but an impressive variety of carapace shapes.


Assuntos
Crustáceos , Animais , Brasil , Espécies Introduzidas , Masculino , Rios
14.
Mar Environ Res ; 162: 105134, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33032079

RESUMO

Multi-use marine protected areas (MPAs) are increasingly designated towards achieving global conservation targets. To develop effective management, the impact of permitted activities must be understood. Potting for shellfish occurs on temperate rocky reefs globally with impact not fully quantified. This UK-based study used underwater video to quantify (a) benthic condition of rocky reefs, (b) mechanisms of potting interaction and (c) true footprint of potting. Assemblages in static gear areas were more indicative of a healthy reef than those in mixed gear areas. Damage was recorded during pot hauling, but the area of damage was not the entire pot haul path. 25-30% of individuals were damaged (commonly through tissue abrasion) or removed. Notably, damage occurred to some long-lived, slow growing taxa raising concerns over impacts. Potting is more destructive than previously thought and managers must balance ecology with social and economic considerations to determine what level of impact is acceptable.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Animais , Recifes de Corais , Crustáceos , Ecologia , Peixes , Humanos , Alimentos Marinhos
15.
Int J Nanomedicine ; 15: 8097-8108, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33116520

RESUMO

Background: Metallic nanoparticles (NPs) are highly exploited in manufacturing and medical processes in a broad spectrum of industrial applications and in the academic sectors. Several studies have suggested that many metallic nanomaterials including those derived by silver (Ag) are entering the ecosystem to cause significant toxic consequences in cell culture and animal models. However, ecotoxicity studies are still receiving limited attention when designing functionalized and non.-functionalized AgNPs. Objective: This study aimed to investigate different ecotoxicological profiles of AgNPs, which were analyzed in two different states: in pristine form uncoated AgNPs and coated AgNPs with the antimicrobial peptide indolicidin. These two types of AgNPs are exploited for a set of different tests using Daphnia magna and Raphidocelis subcapitata, which are representatives of two different levels of the aquatic trophic chain, and seeds of Lepidium sativum, Cucumis sativus and Lactuca sativa. Results: Ecotoxicological studies showed that the most sensitive organism to AgNPs was crustacean D. magna, followed by R. subcapitata and plant seeds, while AgNPs coated with indolicidin (IndAgNPs) showed a dose-dependent decreased toxicity for all three. Conclusion: The obtained results demonstrate that high ecotoxicity induced by AgNPs is strongly dependent on the surface chemistry, thus the presence of the antimicrobial peptide. This finding opens new avenues to design and fabricate the next generation of metallic nanoparticles to ensure the biosafety and risk of using engineered nanoparticles in consumer products.


Assuntos
Peptídeos Catiônicos Antimicrobianos/toxicidade , Organismos Aquáticos/efeitos dos fármacos , Ecossistema , Ecotoxicologia , Nanopartículas Metálicas/toxicidade , Prata/toxicidade , Animais , Peptídeos Catiônicos Antimicrobianos/síntese química , Crustáceos/efeitos dos fármacos , Cucumis sativus/efeitos dos fármacos , Cucumis sativus/crescimento & desenvolvimento , Daphnia/citologia , Daphnia/efeitos dos fármacos , Germinação/efeitos dos fármacos , Lepidium/efeitos dos fármacos , Lepidium/crescimento & desenvolvimento , Alface/efeitos dos fármacos , Alface/crescimento & desenvolvimento , Nanopartículas Metálicas/ultraestrutura , Sementes/efeitos dos fármacos , Sementes/crescimento & desenvolvimento , Testes de Toxicidade
16.
An Acad Bras Cienc ; 92(suppl 2): e20190459, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33084759

RESUMO

In order to characterize Patagonian (Argentina) ecoregions using non-marine ostracods, their associations in 69 environments were assessed. Twenty eight taxa were recorded, including 12 endemic of the Neotropical region. Our results indicate that Patagonian ostracods are mainly influenced by electrical conductivity (EC), altitude, pH, and temperature; and shows a correlation with Argentinian ecoregions. Assemblage I is composed of sites located at high altitude in the Andean Patagonian forest ecoregion. Host waters have low temperature, EC and pH, and support as representative species Cypris pubera, Eucypris virens, Bradleystrandesia fuscata, Tonacypris lutaria and Amphicypris nobilis. Assemblage II, related to mid-altitude environments in the Patagonian Steppe ecoregion, thrived in waters with moderate to high EC, and alkaline pH values. Dominant species includes Limnocythere rionegroensis, L. patagonica, E. virgata, Riocypris whatleyi, Riocypris sarsi, Newnhamia patagonica, Kapcypridopsis megapodus, Ilyocypris ramirezi and Penthesinelula incae. Assemblage III inhabited environments within Monte and Espinal ecoregions, situated in the eastern part of the study area at low altitude, EC moderate and temperate waters, supporting Heterocypris hyalinus, Amphicypris argentinensis, Sarscypridopsis aculeata, Cypridopsis vidua, Herpetocypris intermedia and Chlamidotheca incisa. Our results indicates that Argentinian Patagonia hosts a diverse ostracod fauna and highlights their capacity as proxies in ecological and palaeoenvironmental studies.


Assuntos
Crustáceos , Florestas , Altitude , Animais , Argentina
17.
Proc Biol Sci ; 287(1935): 20201661, 2020 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-32933445

RESUMO

The bivalved crustacean ostracods have the richest fossil record of any arthropod group and display complex reproductive strategies contributing to their evolutionary success. Sexual reproduction involving giant sperm, shared by three superfamilies of living ostracod crustaceans, is among the most fascinating behaviours. However, the origin and evolution of this reproductive mechanism has remained largely unexplored because fossil preservation of such features is extremely rare. Here, we report exceptionally preserved ostracods with soft parts (appendages and reproductive organs) in a single piece of mid-Cretaceous Kachin amber (approximately 100 Myr old). The ostracod assemblage is composed of 39 individuals. Thirty-one individuals belong to a new species and genus, Myanmarcypris hui gen. et sp. nov., exhibiting an ontogenetic sequence from juveniles to adults (male and female). Seven individuals are assigned to Thalassocypria sp. (Cypridoidea, Candonidae, Paracypridinae) and one to Sanyuania sp. (Cytheroidea, Loxoconchidae). Our micro-CT reconstruction provides direct evidence of the male clasper, sperm pumps (Zenker organs), hemipenes, eggs and female seminal receptacles with giant sperm. Our results reveal that the reproduction behavioural repertoire, which is associated with considerable morphological adaptations, has remained unchanged over at least 100 million years-a paramount example of evolutionary stasis. These results also double the age of the oldest unequivocal fossil animal sperm. This discovery highlights the capacity of amber to document invertebrate soft parts that are rarely recorded by other depositional environments.


Assuntos
Crustáceos/anatomia & histologia , Genitália Masculina , Espermatozoides , Âmbar , Animais , Artrópodes , Feminino , Fósseis , Genitália , Masculino , Reprodução , Microtomografia por Raio-X
18.
Ecotoxicol Environ Saf ; 203: 111022, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32888608

RESUMO

To evaluate the aquatic hazards of the insect juvenile hormone analogue fenoxycarb, a single application (0, 48.8, 156.3, 500, 1600, and 5120 µg/L) of it was done in indoor freshwater systems dominated by Daphnia carinata (daphnid) and Dolerocypris sinensis (ostracoda). The responses of zooplankton (counted by abundance and the activity and immuno-reactive content of free N-Acetyl-ß-D-glucosaminidase (NAGase)), phytoplankton (counted by chlorophyll and phycocyanin), planktonic bacteria and fungi, and some water quality parameters were investigated in a period of 35 d. Results of the study showed that the ostracoda was more sensitive than daphnid, with time-weighted average (TWA)-based no observed effect concentrations (NOECs) to be 8.45 and 12.66 µg/L in systems without humic acid addition (HA-) and to be 6.37 and 9.54 µg/L in systems with humic acid addition (HA+). The duration of treatment-related effects in the ostracoda population was longer than the daphnid population (21 vs. 14 days). Besides, the data analysis indicated that the toxicity of fenoxycarb was significantly enhanced in the HA+ systems. Owing to the reduced grazing pressure, the concentrations of chlorophyll and phycocyanin increased in the two highest treatments. The increase in photosynthesis along with a reduced animal excretion led to an increase in pH and a decrease in nutrient contents. These changes seemed to have an effect on the microbial communities. For example, the abundances of some opportunistic pathogens of aquatic animals (e.g. Aeromonas and Cladosporium) and organic-pollutant-degrading microorganisms (e.g. Ancylobacter and Azospirillum) increased significantly in microbial communities, but the abundances of Pedobacter, Candidatus Planktoluna, and Rhodobacter (photosynthetic bacteria) markedly decreased. This study provides useful information to understand the ecotoxicological impacts of fenoxycarb at the population and community levels while integrating the effects of HA on toxicity.


Assuntos
Crustáceos/efeitos dos fármacos , Daphnia/efeitos dos fármacos , Água Doce/química , Fenilcarbamatos/toxicidade , Fitoplâncton/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Zooplâncton/efeitos dos fármacos , Animais , Ecotoxicologia , Substâncias Húmicas/efeitos adversos , Substâncias Húmicas/análise , Microbiota/efeitos dos fármacos
19.
Aquat Toxicol ; 227: 105569, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32916319

RESUMO

Pharmaceuticals are widespread contaminants across the aquatic systems and despite the role that these compounds play in society today, little is known about their effects in aquatic organisms once they are released into the environment. This study aims to provide quantitative insight on the effects of antidepressants on the reproduction of fish and crustaceans with a multilevel meta-analysis. A systematic literature search identified 19 studies investigating effects of antidepressant exposure in fish or crustaceans' reproduction, according to specific selection criteria. Heterogeneity analysis was performed and the moderating effect of the range of exposure concentrations, exposure time, organism group and toxicant was tested. Additionally, publication bias was also addressed. The results showed that, overall, there is no significant association between antidepressant exposure and the reproduction of fish and crustaceans, however, moderator analysis revealed that the range of concentrations is a significant moderator for fish and crustacean fecundity, showing contrary results between the two groups. Antidepressant concentration had a small, yet positive effect on fish fecundity, meaning that increased concentrations resulted in increased fish fecundity, whilst a negative effect on crustaceans' fecundity was apparent with increasing concentrations. This difference could be related to data artifacts, or, more likely, evidencing a hormetic dose-response curve, with different ranges of exposure concentrations considered in studies on fish and crustaceans. Antidepressants have shown effects on reproductive outcomes in aquatic organisms, based on individual studies and narrative reviews. However, our results show that other factors can have an important role. Additionally, data available for a quantitative assessment is scarce, focusing mainly on a few freshwater species, low concentration ranges and one SSRI compound, fluoxetine. Thus, more research on the subject is needed since meta-analysis are only as statistically powerful as the number of, good quality, studies they include.


Assuntos
Antidepressivos/toxicidade , Organismos Aquáticos/efeitos dos fármacos , Fluoxetina/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Organismos Aquáticos/fisiologia , Crustáceos/efeitos dos fármacos , Peixes/crescimento & desenvolvimento , Água Doce/química , Reprodução/efeitos dos fármacos
20.
Proc Biol Sci ; 287(1933): 20200730, 2020 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-32811315

RESUMO

Sexual selection often favours investment in expensive sexual traits that help individuals compete for mates. In a rapidly changing environment, however, allocation of resources to traits related to reproduction at the expense of those related to survival may elevate extinction risk. Empirical testing of this hypothesis in the fossil record, where extinction can be directly documented, is largely lacking. The rich fossil record of cytheroid ostracods offers a unique study system in this context: the male shell is systematically more elongate than that of females, and thus the sexes can be distinguished, even in fossils. Using mixture models to identify sex clusters from size and shape variables derived from the digitized valve outlines of adult ostracods, we estimated sexual dimorphism in ostracod species before and after the Cretaceous/Palaeogene mass extinction in the United States Coastal Plain. Across this boundary, we document a substantial shift in sexual dimorphism, driven largely by a pronounced decline in the taxa with dimorphism indicating both very high and very low male investment. The shift away from high male investment, which arises largely from evolutionary changes within genera that persist through the extinction, parallels extinction selectivity previously documented during the Late Cretaceous under a background extinction regime. Our results suggest that sexual selection and the allocation of resources towards survival versus reproduction may be an important factor for species extinction during both background and mass extinctions.


Assuntos
Crustáceos , Extinção Biológica , Preferência de Acasalamento Animal , Caracteres Sexuais , Animais , Evolução Biológica , Feminino , Fósseis , Masculino
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