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1.
Toxicon ; 191: 9-17, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33338449

RESUMO

Brevetoxins were confirmed in urine specimens from patients diagnosed with neurotoxic shellfish poisoning (NSP) after consumption of gastropods that were recreationally harvested from an area previously affected by a Karenia brevis bloom. Several species of gastropods (Triplofusus giganteus, Sinistrofulgur sinistrum, Cinctura hunteria, Strombus alatus, Fulguropsis spirata) and one clam (Macrocallista nimbosa) from the NSP implicated gastropod collection area (Jewfish Key, Sarasota Bay, Florida) were examined for brevetoxins using liquid chromatography-tandem mass spectrometry (LC-MS/MS) and enzyme-linked immunosorbent assay (ELISA). All gastropods and the clam were contaminated with brevetoxins. Composite B-type toxin concentrations in gastropods ranged from 1.1 to 198 µg BTX-3 equiv./g by ELISA, levels likely capable of causing NSP in consumers. Several brevetoxin metabolites previously characterized in molluscan shellfish were identified in these gastropods. Brevetoxin analog profiles by ELISA were similar in the gastropod species examined. This work documents the occurrence of NSP through consumption of a type of seafood not typically monitored in Florida to protect human health, demonstrating the need to better assess and communicate the risk of NSP to gastropod harvesters in Karenia brevis endemic areas.


Assuntos
Toxinas Marinhas/urina , Oxocinas/urina , Intoxicação por Frutos do Mar/epidemiologia , Animais , Bioensaio , Bivalves , Cromatografia Líquida , Dinoflagelados , Ensaio de Imunoadsorção Enzimática , Florida/epidemiologia , Gastrópodes , Humanos , Frutos do Mar , Espectrometria de Massas em Tandem
2.
Aquat Toxicol ; 230: 105694, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33316747

RESUMO

Psychotropics, especially benzodiazepines, are commonly prescribed worldwide. Poorly eliminated at wastewater treatment plants, they belong to a group of emerging contaminants. Due to their interaction with the GABAA receptor, they may affect the function of the nervous system of non-target organisms, such as aquatic organisms. The toxicity of oxazepam, a very frequently detected benzodiazepine in continental freshwater, has been largely studied in aquatic vertebrates over the last decade. However, its effects on freshwater non-vertebrates have received much less attention. We aimed to evaluate the long-term effects of oxazepam on the juvenile stage of a freshwater gastropod widespread in Europe, Radix balthica. Juveniles were exposed for a month to environmentally-relevant concentrations of oxazepam found in rivers (0.8 µg/L) and effluents (10 µg/L). Three main physiological functions were studied: feeding, growth, and locomotion. Additionally, gene expression analysis was performed to provide insights into toxicity mechanisms. There was a strong short-term activation of the feeding rate at low concentration, whereas the high dose resulted in long-term inhibition of food intake. A significant decrease in mortality rate was observed in juveniles exposed to the lowest dose. Shell growth and locomotor activity did not appear to be affected by oxazepam. Transcriptomic analysis revealed global over-expression of genes involved in the nervous regulation of the feeding, digestive, and locomotion systems after oxazepam exposure. The molecular analysis also revealed a possible interference of animal manipulation with the molecular effects induced by oxazepam exposure. Overall, these results improve our understanding of the effects of the psychoactive drug oxazepam on an aquatic mollusc gastropod.


Assuntos
Organismos Aquáticos/efeitos dos fármacos , Comportamento Alimentar/efeitos dos fármacos , Gastrópodes/efeitos dos fármacos , Oxazepam/toxicidade , Transcriptoma/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Organismos Aquáticos/genética , Organismos Aquáticos/crescimento & desenvolvimento , Relação Dose-Resposta a Droga , Gastrópodes/genética , Gastrópodes/crescimento & desenvolvimento , Atividade Motora/efeitos dos fármacos , Oxazepam/análise , Rios/química , Poluentes Químicos da Água/análise
3.
Biol Bull ; 239(3): 189-208, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33347799

RESUMO

AbstractThe catecholamine 3,4-dihydroxyphenethylamine, or dopamine, acts as a neurotransmitter across a broad phylogenetic spectrum. Functions attributed to dopamine in the mammalian brain include regulation of motor circuits, valuation of sensory stimuli, and mediation of reward or reinforcement signals. Considerable evidence also supports a neurotransmitter role for dopamine in gastropod molluscs, and there is growing appreciation for its potential common functions across phylogeny. This article reviews evidence for dopamine's transmitter role in the nervous systems of gastropods. The functional properties of identified dopaminergic neurons in well-characterized neural circuits suggest a hypothetical incremental sequence by which dopamine accumulated its diverse roles. The successive acquisition of dopamine functions is proposed in the context of gastropod feeding behavior: (1) sensation of potential nutrients, (2) activation of motor circuits, (3) selection of motor patterns from multifunctional circuits, (4) valuation of sensory stimuli with reference to internal state, (5) association of motor programs with their outcomes, and (6) coincidence detection between sensory stimuli and their consequences. At each stage of this sequence, it is proposed that existing functions of dopaminergic neurons favored their recruitment to fulfill additional information processing demands. Common functions of dopamine in other intensively studied groups, ranging from mammals and insects to nematodes, suggest an ancient origin for this progression.


Assuntos
Dopamina , Gastrópodes , Animais , Moluscos , Neurotransmissores , Filogenia
4.
Zootaxa ; 4861(3): zootaxa.4861.3.6, 2020 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-33311216

RESUMO

Increasing discoveries of new species of the genus Melanochlamys Cheeseman, 1881 in the recent years indicate that the biodiversity of this group remains underestimated. Recently, several aglajid sea slugs were collected from Laizhou Bay, Shandong Province, China. Morphological observation of their external and internal anatomy revealed that they represent an undescribed species of Melanochlamys. This new species, Melanochlamys aquilina sp. nov., is closely related to Melanochlamys fukudai Cooke, Hanson, Hirano, Ornelas-Gatdula, Gosliner, Chernyshev Valdés, 2014 in body size and dark external coloration, but can be differentiated from the latter by features of both shell and male reproductive organ. Phylogenetic analyses of two mitochondrial (COI, 16S rRNA) and a nuclear (H3) genes using Bayesian inference, maximum likelihood, and species delimitation analysis also support the separation of Melanochlamys aquilina sp. nov. from its related congeners.


Assuntos
Gastrópodes , Animais , Teorema de Bayes , China , Gastrópodes/genética , Masculino , Filogenia , RNA Ribossômico 16S
5.
Zootaxa ; 4890(1): zootaxa.4890.1.1, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33311242

RESUMO

Nudibranchs in the family Discodorididae are generally medium (~30mm) to large ( 50mm) in size, sometimes cryptic, and are found in almost every marine ecosystem around the world. The diversity and systematics of the genera within Discodorididae are poorly understood and have led to numerous taxonomic changes. Hoplodoris Bergh, 1880 has recently been considered a synonym of Asteronotus Ehrenberg, 1831; however, morphological and molecular phylogenetic analyses reveal a distinct separation between these two genera. Here we provide a re-description of the type species Hoplodoris desmoparypha as well as descriptions of four undescribed species of Asteronotus and Hoplodoris. Bayesian inference and maximum likelihood analyses of two mitochondrial and two nuclear genes were used to evaluate the phylogenetic positions of the new species and clarify the relationships between Asteronotus and Hoplodoris to the rest of the Discodorididae. Based on our results, Hoplodoris is removed from synonymy with Asteronotus. Descriptions for Asteronotus markaensis sp. nov., and Asteronotus namuro sp. nov. from the Red Sea, as well as Hoplodoris balbon sp. nov. and Hoplodoris rosans sp. nov. from the western Pacific are provided.


Assuntos
Ecossistema , Gastrópodes , Animais , Teorema de Bayes , Filogenia
6.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 32(5): 441-447, 2020 Jun 12.
Artigo em Chinês | MEDLINE | ID: mdl-33185052

RESUMO

Before and after the construction of the South-to-North Water Diversion Project, a number of studies have been conducted to assess the possibility of the northward spread of Oncomelania snails and schistosomiasis caused by the construction of the project, the survival and reproduction of snails moved north of their natural distribution, and the transmission of schistosomiasis by the survival snails moved north of their natural distribution. The effect of the South-to-North Water Diversion Project on the transmission of schistosomiasis is restricted along the Jiangsu section of the eastern route project of the South-to-North Water Diversion Project, and the Water Transfer Project from the Yangtze River to Han River of the middle route project of the South-to-North Water Diversion Project. It has been demonstrated the water diversion pattern via the pump stations and the ecological conditions in the water transfusion channels of the South-to-North Water Diversion Project are unlikely to result in the northward spread of Oncomelania snails or schistosomiasis, and no snails or schistosomiasis spread was found during the surveillance before and after the operation of the eastern route project of the South-to-North Water Diversion Project, and the Water Transfer Project from the Yangtze River to Han River of the middle route project of the South-to-North Water Diversion Project. Nevertheless, sustainable surveillance of Oncomelania snails along the South-to-North Water Diversion Project will provide scientific support and safety guarantee for the construction and operation of the subsequent projects.


Assuntos
Gastrópodes , Esquistossomose , Abastecimento de Água , Animais , China/epidemiologia , Rios , Esquistossomose/epidemiologia , Esquistossomose/prevenção & controle , Água
7.
Elife ; 92020 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-33215989

RESUMO

Sea slugs increase the longevity of the chloroplasts they steal from algae by limiting the harmful side-effects of photosynthesis.


Assuntos
Gastrópodes , Fotossíntese , Animais , Aplysia , Cloroplastos/metabolismo , Roubo
8.
Mar Environ Res ; 162: 105180, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33126112

RESUMO

The intertidal zone is an especially stressful thermal habitat, typically exposing residents to air temperatures for up to 6 h at a time, twice daily. Tolerance to elevated temperatures has been particularly well-studied for a variety of intertidal species, especially with regard to upper thermal limits during summers. However, in recent years, as climates have been changing around the world, temperate zone intertidal organisms have sometimes been exposed to periods of unusually high air temperatures during the winter. The present study sought to examine the impact of elevated temperatures on survival and clearance rates of winter-acclimated intertidal individuals of the sedentary marine suspension-feeding gastropod Crepidula fornicata. Individuals were collected intertidally from Nahant, Massachusetts from late January to early April each year for 5 years, maintained in the laboratory at the acclimation temperature of 6 °C, and exposed in the laboratory for 3 h to temperatures as high as 37 °C in seawater either once or twice, 24 h apart. Although mean clearance rates were substantially reduced for at least the next 12-24 h after individuals were returned to the 6 °C control condition following exposures to elevated temperatures as low as 21-26 °C, we saw little mortality even following two 3 h exposures to 35 °C, or single exposures to 37 °C. Mortality was substantial, however, in one experiment following a double exposure to 37 °C. Smaller individuals (~5-12 mm in shell length) were somewhat more sensitive to the thermal stress than adults were. Intertidal members of C. fornicata in Massachusetts seem well-prepared to deal with the increasing range of winter air temperatures associated with the global climate confusion predicted for future years. Additional studies will be required to understand the physiological and biochemical mechanisms used by winter-acclimated individuals of this species to tolerate such periodic substantial temperature increases of 29-31 °C.


Assuntos
Gastrópodes , Aclimatação , Animais , Temperatura Alta , Humanos , Estações do Ano , Temperatura
9.
Bull Environ Contam Toxicol ; 105(5): 728-735, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33079216

RESUMO

Imposex is a phenomenon widely associated with environmental exposure to organotin compounds which were quite common components of antifouling paints applied on boats and ship hulls. Here we study the incidence of imposex in neogastropods and its relation with water quality and maritime traffic in the coastal strip of Santa Marta, Colombia. Imposex was determined via specialized indexes and related to the organisms' size, somatic conditions, variables of water quality and maritime traffic, in a space-time assessment. There was evidence of imposex in five species Plicopurpura patula, Vasula deltoidea, Stramonita haemastoma, S. floridana, and Gemophos auritulus. Purpura patula and Vasula deltoidea species were found in all sampling sites. The results have proved that imposex is highly influenced by the maritime traffic variable, with greater prevalence during the dry season, and with P. patula being more sensitive than V. deltoidea.


Assuntos
Transtornos do Desenvolvimento Sexual/induzido quimicamente , Monitoramento Ambiental/métodos , Gastrópodes/efeitos dos fármacos , Compostos Orgânicos de Estanho/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Região do Caribe , Colômbia , Feminino , Gastrópodes/crescimento & desenvolvimento , Masculino , Pintura , Estações do Ano , Qualidade da Água
10.
Sci Total Environ ; 748: 142448, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33113697

RESUMO

In the Southern Ocean, warming and freshening are expected to be prominent signals of climate change and the reduced ability of Antarctic marine organisms to cope with changing environmental conditions could challenge their future survival. The Antarctic limpet Nacella concinna is a macroinvertebrate of rocky ecosystems, which occurs in high densities in the shallow subtidal zone. Subtidal individuals were exposed to a combination of temperatures (1, 4, 8, 11, 14 °C) and salinities (20 and 30 psu) for a 60-day period. A drastic increment in mortality was observed with seawater warming, showing that N. concinna is highly stenothermal, with limited ability to survive at temperatures warmer than 4 °C, although there was some degree of acclimation at 4 °C and ambient salinity (30 psu). This study confirmed the stenohaline characteristic of this species, with mortality reaching 50% and lower scope for growth at low salinity (20 psu) even at the control temperature (1 °C). At the sub-cellular level, limpets' low tolerance to out-of range salinity is illustrated by the activation of cell remodelling processes whereas the down-regulation of chaperones proteins and plasma membrane ATPase suggest that under the combination of warming and freshening N. concinna experiences a severe level of stress and devote much of its energy to somatic maintenance and survival. The drastic effect observed can be explained by its subtidal origin, an environment with more stable conditions. The surviving individuals at 1 °C and lowered salinity (20 psu) were either more tolerant or showing signs of acclimation after 60 days, but the combination of warming and freshening have a greater combined stress. Projections of climate change for end of the century for this part of the Antarctic can, therefore, result in a significant diminution of the subtidal population of N. concinna, affecting ecological interactions and diversity of the food web.


Assuntos
Ecossistema , Gastrópodes , Animais , Regiões Antárticas , Humanos , Oceanos e Mares , Água do Mar , Temperatura , Transcriptoma
11.
Oecologia ; 194(3): 455-463, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33064215

RESUMO

Sacoglossan sea slugs can 'steal' chloroplasts from their algal food and use them for photosynthesis (kleptoplasty). Although it has been shown that light has positive effects on survival and body size retention of some sacoglossans likely through photosynthesis, it is unknown whether light affects their fitness components such as number of offspring or offspring size. Moreover, whether the effects of light extend over the sacoglossans' lifetime has been unexplored. To assess such long-term effects of light intensity and food availability on fitness components, we conducted a 15.9-week laboratory experiment using Elysia atroviridis under a combination of two light intensities (low or high) and two food conditions (with or without food). The total number of eggs laid was greater in the presence of both strong light and food than in other conditions, suggesting positive effects of both light intensity and food availability. The shell height at hatch was also largest in the presence of strong light and food. Larval rearing experiments showed that the size difference at hatch between conditions corresponded to a 1.19-1.93 days growth and 7.9-18.1% survival increase. Thus, positive effects of light and food on the fitness components extend over the lifetime of E. atroviridis.


Assuntos
Gastrópodes , Fotossíntese , Animais , Cloroplastos/metabolismo , Alimentos
12.
Zootaxa ; 4819(3): zootaxa.4819.3.1, 2020 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-33056090

RESUMO

This paper describes four new Chromodoris species: Chromodoris balat sp. nov., Chromodoris baqe sp. nov., Chromodoris kalawakan sp. nov., and Chromodoris quagga sp. nov. We were able to distinguish 44 species level lineages within Chromodoris, expanding the Indo-Pacific species from 39 species. The phylogeny presented here provides slightly greater resolution of species relationships than do previous studies of this genus. Layton et al. (2018), determined that variable color patterns made it difficult to differentiate in living specimens of distinct species, but we provide some additional stable color characters that potentially help resolve this issue, as well as additional internal features that are useful in species delimitation and correlate with the molecular phylogenetic analysis.


Assuntos
Gastrópodes , Animais , Filogenia
13.
Zootaxa ; 4827(1): zootaxa.4827.1.1, 2020 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-33056259

RESUMO

Nearly one hundred names have been proposed for Caecidae within the eastern Pacific. For the first time a comprehensive review of the extant members of Caecidae has been completed for this region. During this twelve year long deciphering effort, tens of thousands of specimens from Alaska to Chile were examined. All known type material was studied and whenever possible has been illustrated herein.                Whenever possible the descriptions include details of each growth stage from the protoconch through to the final adult stage. Then, the growth stages have been reconstructed to show what the caecid might have looked like, if it had not discarded its previous stages. In doing so, a better understanding of the growth morphology is provided for each species. In addition, this effort shows that not only the apertures of late subadult stages can appear different from their adult stage, but there can also be multiple differences in the varices.                The resulting product is a taxonomic resource for Caecidae identification and growth morphology. Forty-three species are treated herein. Neotypes have been designated for Caecum glabriforme, C. semilaeve and C. subaustrale, and a lectotype has been designated for C. mirificum. Five species are described as new to science, plus one replacement name: Caecum lightfootanum sp. nov., C. draperi sp. nov., C. shaskyi sp. nov., C. galapagoense sp. nov. and C. spiculum sp. nov. and C. adamsi nom. nov.


Assuntos
Gastrópodes , Animais , Oceano Pacífico
14.
Zootaxa ; 4782(1): zootaxa.4782.1.1, 2020 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-33056508

RESUMO

A comprehensive discussion and survey is made of all North American Paleogene and Late Cretaceous pteropods, and their systematics reviewed. From the West Coast of North America pteropod fossils have been collected from 23 localities in Washington State, and from the Gulf Coastal Plain they have been found in 40 localities. We also review earlier published specimens from boreholes in the Atlantic Coastal Plain. As a result, six new species are introduced from the Gulf Coast (Currylimacina asperita Garvie sp. nov., Heliconoides hodgkinsoni Garvie sp. nov., Limacina texanopsis Garvie sp. nov., Limacina parvabrazensis Garvie Janssen sp. nov., Limacina pseudopygmaea Garvie Janssen sp. nov., Cheilospicata cedrus Garvie sp. nov.) and one from Washington State (Clio gailae Goedert Janssen sp. nov.). The geographical distribution and/or stratigraphic ranges of several species has been extended, for example, Limacina canadaensis Hodgkinson, 1992, is reported for the first time from western North America. Some species originally described from elsewhere, Altaspiratella multispira (Curry, 1982), Heliconoides bartonensis (Curry, 1965), L. karasawai Ando, 2011, L. aff. valvatina (Reuss, 1867), Creseis spina (Reuss, 1867) and Clio chadumica Korobkov, 1966, are reported for the first time from the Americas. New specimens of several poorly known species yielded additional information on morphology or biostratigraphy. It is shown that some species have longer temporal ranges in America, occurring in, or continuing into younger deposits than those in Europe. In addition to the only Cretaceous pteropod from Washington State known so far, several enigmatic species possibly representing Pteropoda are described from the Late Cretaceous (Maastrichtian) and Danian of Texas, which allows a salient discussion on the early history of Pteropoda. An enigmatic specimen from the Eocene of Texas might represent a very early form of Gymnosomata. This analysis shows that there may be more pteropod species represented during the Late Cretaceous and Paleocene than previously suspected.


Assuntos
Gastrópodes , Animais , Moluscos , Filogenia
15.
Zootaxa ; 4767(3): zootaxa.4767.3.3, 2020 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-33056555

RESUMO

Herein we revise several Recent Mediterranean species of the rissoid genus Alvania Risso, 1826: Alvania scabra (Philippi, 1844), Alvania sculptilis (Monterosato, 1877), Alvania sororcula Granata-Grillo, 1877, Alvania lucinae Oberling, 1970, Alvania josefoi Oliver Templado, 2009 and Alvania scuderii Villari, 2017. They represent a rather homogeneous group of morphologically similar species, referred to as the Alvania scabra complex, which includes also some other species from the northeastern Atlantic. We designate a neotype for Rissoa scabra Philippi, 1844 and a lectotype for Rissoa oranica Pallary, 1900 to stabilize the use of the names. Alvania oranica (Pallary, 1900) is confirmed as a synonym of Alvania scabra (Philippi, 1844), and Alvania asperella (Granata-Grillo, 1877) is proposed as a synonym of Alvania sororcula (Granata-Grillo, 1877) [new synonymy]. Finally, we describe one new Mediterranean species: Alvania pizzinii Amati, Smriglio Oliverio n. sp. from Levanzo Is., Sicily.


Assuntos
Gastrópodes , Animais , Mar Mediterrâneo , Moluscos
16.
Zootaxa ; 4766(1): zootaxa.4766.1.1, 2020 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-33056603

RESUMO

A new Permian gastropod assemblage from the Roadian (Middle Permian) Khao Khad Formation, Saraburi Group (Lopburi Province, Central Thailand) which is part of the Indochina Terrane, has yielded one of the most diverse Permian gastropod faunas known from Thailand. A total of 44 gastropod species belonging to 30 genera are described herein, including thirteen new species and one new genus. The new genus is Altotomaria. The new species are Bellerophon erawanensis, Biarmeaspira mazaevi, Apachella thailandensis, Gosseletina microstriata, Worthenia humiligrada, Altotomaria reticulata, Yunnania inflata, Trachydomia suwanneeae, Trachyspira eleganta, Heterosubulites longusapertura, Platyzona gradata, Trypanocochlea lopburiensis and Streptacis? khaokhadensis. Most of the species in the studied assemblage represent vetigastropods  (35.6%) and caenogastropods (26.7%) and most of the species belong to Late Palaeozoic cosmopolitan genera. The studied faunas come from shallow water carbonates that are rich in fusulinids, followed by gastropods, ostracods, bivalves and brachiopods. The gastropod assemblage from the Khao Khad Formation shares no species with the gastropod assemblages from other Permian formations in Thailand, the Tak Fa Limestone and the Ratburi Limestone. However, it is similar to the Late Permian gastropod faunas from South China of the Palaeo-Tethys, therefore it suggests that the Indochina Terrane was not located far from South China.


Assuntos
Gastrópodes , Animais , Fósseis , Indochina , Tailândia
17.
Zootaxa ; 4851(1): zootaxa.4851.1.3, 2020 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-33056738

RESUMO

The identity of Archierato maugeriae (Gray in Sowerby I, 1832) comb. nov., A. martinicensis (Schilder, 1933) comb. nov. and A. dalli (Morretes, 1941) comb. nov. from the Western Atlantic as well as of A. galapagensis (Schilder, 1933), A. columbella (Menke, 1847) comb. nov. and A. panamaensis (Carpenter, 1856) comb. nov. from the east Pacific are clarified based on the type specimens. The assignment to the genus Archierato Schilder, 1933 is confirmed. The clarification of the well-known, often misinterpreted taxa results in the description of four new species: Archierato michaelmonti nov. sp., Archierato rhondae nov. sp., Archierato janae nov. sp. and Archierato guadeloupensis nov. sp.


Assuntos
Gastrópodes , Animais
18.
Zootaxa ; 4840(1): zootaxa.4840.1.1, 2020 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-33056795

RESUMO

All reared larvae of flies of the genus Colobaea Zetterstedt, 1837 (Diptera: Sciomyzidae), which comprises 15 valid species, kill and consume freshwater nonoperculate pulmonate snails. New data are presented on the geographic distribution, biology, morphology of immature stages, and classification of Colobaea. Life cycle information is provided from field data and laboratory rearings for four of the 11 Palearctic species-C. bifasciella (Fallén), C. deemingi Knutson Bratt n.sp., C. pectoralis (Zetterstedt), and C. punctata (Lundbeck)-and for one of the three Nearctic species, C. americana Steyskal. Colobaea bifasciella is shown to be one of the most highly specialized parasitoid Sciomyzini, laying eggs on shells of Galba truncatula (O.F. Müller) and Stagnicola palustris (O.F. Müller) in temporary, intermittent, or vernal semiterrestrial situations. Each larva feeds in only one host snail, which is not killed until shortly before the larva completes development. Puparia are strongly modified to fit tightly within the shell of the host. The other reared species are shown to be less specialized than C. bifasciella, with eggs being laid upon vegetation, the larvae behaving as parasitoids-predators-saprophages of exposed aquatic snails, and the puparia of all four species being adapted to a lesser degree than C. bifasciella to fitting within the shell of the host snail. In nature, C. americana attacks Gyraulus parvus (Say) and Physa Draparnaud sp.; C. pectoralis attacks Anisus vortex (L.) and Bathyomphalus contortus (L.); and C. punctata attacks Gyraulus albus O.F. Müller, Lymnaea "peregra," Planorbarius corneus (L.), and Planorbis planorbis (L.). In the laboratory, these species also attacked and consumed other freshwater nonoperculate snails; C. deemingi was reared on Gyraulus intermixtus (Mousson) and Radix gedrosiana (Say), and an adult fly of the Palearctic C. distincta (Meigen) emerged from a puparium found in the shell of Anisus spirorbis (L.) collected in nature. Described and figured are eggs, larvae of all three instars, and puparia of the five laboratory-reared species. To provide perspective on features of Colobaea, diagnostic features are summarized of the immature stages of the Sciomyzini and the suprageneric categories of Sciomyzidae. The biogeography of the tribe Sciomyzini is presented, along with details of known geographical distribution. The classification and phylogenetic position of Colobaea are discussed. Included are a checklist of all known taxa of Colobaea, maps of geographic distribution, and a key to adults of the 15 valid species.


Assuntos
Dípteros , Gastrópodes , Animais , Água Doce , Larva , Filogenia
19.
Zootaxa ; 4759(4): zootaxa.4759.4.11, 2020 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-33056901

RESUMO

Recent and fossil global scissurellids were monographed by Geiger (2012) and additional species were recently described from Brazil (Pimenta Geiger 2015). Here, we describe an additional fossil species from shallow water strata of the late Eocene Gries Ranch Formation in Lewis County, Washington State, USA.


Assuntos
Gastrópodes , Animais , Fósseis , Washington
20.
Zootaxa ; 4759(3): zootaxa.4759.3.13, 2020 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-33056916

RESUMO

Ganesa bujnitzkii Gorbunov, 1946 was described from the bathyal of the Arctic Ocean north to the Laptev Sea based on only two specimens, which were the only representatives of this species mentioned by Gorbunov (1946b). Galkin (1955) noted that the shell sculpture of Ganesa bujnitzkii is similar to that of Cyclostrema valvatiodes (Jeffreys, 1883), and that the radula of the G. bujnitzkii differs from other species of the genus Ganesa Jeffreys, 1883 and members of the family Trochidae. Later, based on the original description, Warén (1993) proposed that the species may belong to the genus Skenea; however, he did not examine the type specimen. This opinion was reiterated by Kantor Sysoev (2006).


Assuntos
Gastrópodes , Animais , Regiões Árticas , Masculino
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