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New Virgulid Cercaria (Trematoda, Lecithodendroidea) from the Mollusk Melanopsis praemorsa (Melanopsidae) from Azerbaijan Water Bodies. Morphology and Chaetotaxy of Cercaria agstaphensis 11
A. A. Manafov
Vestnik Zoologii , 2011, DOI: 10.2478/v10058-011-0007-4
Abstract: An illustrated morphological description with chaetotaxy and differential diagnosis of the new form of virgulid cercaria — Cercaria agstaphensis 11 from freshwater prosobranchial mollusks Melanopsis praemorsa (Linnaeus, 1758) are given. Special attention is paid to the tegument armament, the structure of glandular apparatus, excretory system, digestive system, the structure of the sensory apparatus and other larval morphological characters.
New Virgulid Cercaria (Trematoda, Lecithodendroidea) from Freshwater Mollusk Melanopsis praemorsa (Melanopsidae) from Azerbaijan Water Bodies. Morphology and Chaetotaxy of Cercaria Agstaphensis 31
A. A. Manafov
Vestnik Zoologii , 2012, DOI: 10.2478/v10058-012-0001-5
Abstract: An illustrated morphological description with chaetotaxy and differential diagnosis of a new virgulid cercaria - Cercaria agstaphensis 31 from the freshwater prosobranchial mollusk Melanopsis praemorsa (Linnaeus, 1758) are given. Special attention is paid to the arming of the tegument, structure of the glandular apparatus, excretory system, digestive system, structure of the sensory apparatus and other larval morphological characters.
Rediscovery of Leptoxis compacta (Anthony, 1854) (Gastropoda: Cerithioidea: Pleuroceridae)  [PDF]
Nathan V. Whelan, Paul D. Johnson, Phil M. Harris
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0042499
Abstract: The Mobile River Basin is a hotspot of molluscan endemism, but anthropogenic activities have caused at least 47 molluscan extinctions, 37 of which were gastropods, in the last century. Nine of these suspected extinctions were in the freshwater gastropod genus Leptoxis (Cerithioidea: Pleuroceridae). Leptoxis compacta, a Cahaba River endemic, has not been collected for >70 years and was formally declared extinct in 2000. Such gastropod extinctions underscore the imperilment of freshwater resources and the current biodiversity crisis in the Mobile River Basin. During a May 2011 gastropod survey of the Cahaba River in central Alabama, USA, L. compacta was rediscovered. The identification of snails collected was confirmed through conchological comparisons to the L. compacta lectotype, museum records, and radulae morphology of historically collected L. compacta. Through observations of L. compacta in captivity, we document for the first time that the species lays eggs in short, single lines. Leptoxis compacta is restricted to a single location in the Cahaba River, and is highly susceptible to a single catastrophic extinction event. As such, the species deserves immediate conservation attention. Artificial propagation and reintroduction of L. compacta into its native range may be a viable recovery strategy to prevent extinction from a single perturbation event.
Allometry of the Gastropod Melanopsis praemorsa (Thiaridae: Prosobranchia) From Azraq Oasis, Jordan  [PDF]
Ali Z. Elkarmi,Naim S. Ismail
Pakistan Journal of Biological Sciences , 2006,
Abstract: A total of 300 specimens of the freshwater gastropod Melanopsis praemorsa (Thiaridae: Prosobranchia) from Azraq Oasis, Jordan, were studied for age, growth and shell morphometrics. Nonlinear and linear allometric analysis, Von Bertalanfi`s and Richard`s growth models were used to analyze the results. The results show the life span to be five years and the mean observed lengths of the five age cohorts range from 9.6 to 20.6 mm. The theoretical maximum length of this snail may reach 25.7 and 21.4 mm, respectively while the shell and dry body weights averaged 380.8 and 239.8 mg, respectively. The relationships of the shell length to shell and dry body weights are curvilinear and the relationships of the shell length to shell width, aperture length and aperture width are linear. These results are mainly in agreement with the results reported for other snails with similar relationships between the measured snail parameters.
A Faunistic Survey of Cercariae from Fresh Water Snails: Melanopsis spp. and their Role in Transmission Diseases
A Farahnak,R Vafaie-Darian,I Mobedi
Iranian Journal of Public Health , 2006,
Abstract: Snail transmitted diseases are one of the major group of helminth parasitic diseases which have been established by trematode parasites. The larvae of trematodes (cercariae) use the snails as host. The purpose of the present study was to identify of cercariae released from Melanopsis spp. (M. doriae, M. costata, M. praemorsa, and M. nodosa) and evaluate their medical importance. Accordingly, 2, 266 Melanopsis spp. (fresh water snails) were collected from various agriculture canals in the central area of Khuzestan Province in the south west of Iran. 72 (3.1%) infected Melanopsis spp. snails were isolated and the cercariae were obtained by emerging or crushing methods. Subsequently, measurement and drawing were made on cercariae specimens and recognized. In some cases experimental infections were established in the animals for further identification. A total of 4 cercarial families and 1 cercarial group were identified as follows: Heterophyidae: Haplorchis pumilio, H. taithui, Stellantchasmus falcatus and Centrocestus formosanus; Echinostomatidae: Echinochasmus milvi; Cyathocotylidae, Philophthalmidae and Monostome group cercariae (probably Notocotylidae). These results have been recorded for the first time and these cercariae are of medical and veterinary importance.
Incorporación de elementos traza en conchas de Melanopsis durante el crecimiento: posibilidades de aplicación en paleoecología  [cached]
Brito, J.,De Renzi, M.,Bosch, F.,Alonso, J. J.
Estudios Geologicos , 1988, DOI: 10.3989/egeol.88445-6562
Abstract: The living freshwater gastropod Melanopsis dufouri (FERUSSAC) has two morphotypes. The study of chemical variation of trace-elements in this gastropod and its correlation with the environmental fluctuation are the aim of this paper. Due to the genus Melanopsis has an abundant fossil record during the Cenozoic, the results of the present work could be of paleoecological interest. Trace-elements are embodied in the shell during growth. The shell of M. dufouri has accretionary growth. There are several examples cited on circadian accretionary growth in invertebrate shells. However, in the present case and as a first conclusion, the accretion rate depends on the size of the shell. In a short-time field study (l month) that has been carried out we are found some shells with circadian accretion. Chemical compositions of growth lines are generelly not related to dialy fluctuations of environmental parameters. There are gastropods of this species more sensitive to these parameter:> than others. This fact could be due to genetic variability. In a long-time field study (7 months) also carried out, the most significant environmental variation observed concerns to temperature in this period. The chemical composition of one of the two morphotypes is very sensitive to variations of environmental parameters. The other morphotype does not seem to be enough sensitive to environmental variation. The possible circadian accretion rates in M. dufouri does not agree with many general results about accretionary growth of invertebrate shells. It should be interesting analizing the reported cases of Circadian rates in shells under the assumptions of too paper. Paleoecological applications of our results are very difficult for fossil species of Melanopsis. El objetivo del presente trabajo está encaminado al estudio de las variaciones de oligoelementos en la concha de un gasterópodo de agua dulce del género Melanopsis (M. dufouri (FERUSSAC), con dos morfotipos) y si éstas tienen que ver, o no, con la fluctuación de una serie de parámetros ambientales. La importancia del trabajo radica en la posibilidad de la aplicación paleoecológica de sus resultados, ya que el género Melanopsis tiene un abundante registro fósil durante todo el Cenozoico. La incorporación de oligoelementos se efectúa a medida que la concha va creciendo por acreción; lo ideal sería que tal crecimiento fuera circadiano, ya que se podría seguir día a día, sobre la concha, la fluctuación de sus componentes químicos. Sin embargo, nuestro trabajo muestra que, para esta especie, ello no es así. La tasa de acreción, tant
Pannonian molluscs from surroundings of anje near Sevnica, Slovenia  [PDF]
Vasja Miku?
Geologija , 2005,
Abstract: Discussed are Pannonian molluscs found in the surroundings of anje near Sevnica. Prevailing are gastropods of the genus Melanopsis and some rare specimens of the genera Theodoxus, Congeria and Lymnocardium. The most abundant are specimens of the speciesMelanopsis vindobonensis Fuchs, 1870. Found species and sub-species determine the Lower Pannonian age of the rocks. Molluscs in the Upper Miocene rocks at anje can be compared with the Pannonian molluscs of the Vienna Basin and some other sites in the Central Paratethys.
Cassiopid gastropods from the cretaceous of Western Serbia
Banjac Nenad,Bandel Klaus,Kiel Steffen
Geolo?ki Anali Balkanskog Poluostrva , 2007, DOI: 10.2298/gabp0701061b
Abstract: Three species of Cassiopidae (Cerithioidea, Gastropoda) are described from outcrops in the vicinity of the villages Rasti te and Mokra Gora in western Serbia. They occur in marly limestones of near shore shallow water deposits. Earlier micropaleontological investigations have indicated an Albian-Cenomanian age. The species encountered are related to those present in deposits of the European margin of the Tethys and closest relationships exist to those of the Armenian and Transcaucasian region. Our species can be placed in the genera Cassiope, Paraglauconia and Bicarinella. A new species Cassiope kotromanensis is erected. Assumptions about post-mortem shell transport and size sorting of gastropod shells were examined through statistical analysis.
LARVAS DE DIGENEA EN Melanoides tuberculata (GASTROPODA: THIARIDAE) EN MEDELLíN, COLOMBIA
VERGARA,DANIELA; VELáSQUEZ,LUZ ELENA;
Acta Biológica Colombiana , 2009,
Abstract: the larvae of two trematodes found in the freshwater mollusk melanoides tuberculata (gastropoda: thiaridae) are described. 125 snails from the medellin’s botanical garden joaquín antonio uribe were collected. in the laboratory, each individual was placed alone and stimulated with light in order to have cercaria emission. 9.6% of the snails released cercariae. these were separated in three morphologies. from each one, 15 individuals were measured and drawn. photographs were taken. based on their morphological characteritics the presence of centrocestus formosanus (heterophyidae) was determined. the other two morphologies were classified in the family philophthalmidae. one of them constitutes the first register for colombia. the sensibility of m. tuberculata to infections by digeneans, and the specificity of the family philophthalmidae to mollusk hosts of the superfamily cerithioidea are confirmed
LARVAS DE DIGENEA EN Melanoides tuberculata (GASTROPODA: THIARIDAE) EN MEDELLíN, COLOMBIA  [cached]
VERGARA DANIELA,VELáSQUEZ LUZ ELENA
Acta Biológica Colombiana , 2009,
Abstract: RESUMEN Se describen las larvas de digeneos que se obtuvieron en Melanoides tuberculata (Gastropoda: Thiaridae), molusco dulceacuícola del que se colectaron 125 especímenes en el lago del Jardín Botánico Joaquín Antonio Uribe de Medellín. En el laboratorio se individualizaron y se estimuló la emisión cercariana con una fuente luminosa. El 9,6 % de los caracoles emitió cercarias. Los moluscos emisores se sacrificaron para obtener los demás estadios larvarios. Las larvas se montaron al microscopio, se midieron y luego se dibujaron. Los caracteres morfológicos permitieron establecer la presencia de Centrocestus formosanus (Heterophyidae) y de dos Philophthalmidae. Uno de estos es primer registro para Colombia. Se confirma la sensibilidad de M. tuberculata a infecciones por digeneos, así como la especificidad de los filoftálmidos por moluscos hospedadores de la superfamilia Cerithioidea. Palabras claves: cercarias, digenea, Melanoides tuberculata, Philophthalmidae, Redias. ABSTRACT The larvae of two trematodes found in the freshwater mollusk Melanoides tuberculata (Gastropoda: Thiaridae) are described. 125 snails from the Medellina€ s Botanical Garden Joaquín Antonio Uribe were collected. In the laboratory, each individual was placed alone and stimulated with light in order to have cercaria emission. 9.6% of the snails released cercariae. These were separated in three morphologies. From each one, 15 individuals were measured and drawn. Photographs were taken. Based on their morphological characteritics the presence of Centrocestus formosanus (Heterophyidae) was determined. The other two morphologies were classified in the family Philophthalmidae. One of them constitutes the first register for Colombia. The sensibility of M. tuberculata to infections by digeneans, and the specificity of the family Philophthalmidae to mollusk hosts of the superfamily Cerithioidea are confirmed. Key words: Cercariae, Digenea, Melanoides tuberculata, Philophthalmidae, Rediae.
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