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CHROMOSOMES OF THE LIMPET FISSURELLA LIMBATA (SOWERBY, 1835) FROM NORTHERN CHILE (ARCHAEOGASTROPODA: FISSURELLIDAE)
Pinochet-Roco,José; Northland-Leppe,Irma; Capetillo-Arcos,Juana; Jara-Seguel,Pedro;
Gayana (Concepción) , 2008, DOI: 10.4067/S0717-65382008000200015
Abstract: fissurella limbata (sowerby, 1835), presenta un número cromosómico diploide 2n = 32 similar al descrito previamente para otras especies del género fissurella reeve 1849. el juego cromosómico haploide def limbata tiene siete cromosomas metacéntricos, seis submetacéntricos y tres subtelocéntricos. los cromosomas son peque?os y no exceden de 4,0 mm en longitud.
Parasitic castration in Fissurella crassa (Archaeogastropoda) due to an adult Digenea, Proctoeces lintoni (Fellodistomidae)
Oliva, Marcelo E.;
Memórias do Instituto Oswaldo Cruz , 1992, DOI: 10.1590/S0074-02761992000100007
Abstract: specimens of fissurella crassa (archaeogastropoda) from ilo, southern perú, are infected with the adult stage of the digenetic trematode proctoeces lintoni (fellodistomidae). the histopatological analysis of the male and female gonads show a strong effect of the parasite on the structure and function of these organs. p. lintoni live unencysted in the gonads, and the main mechanical damage is originated by the action of a well developed acetabulum. chemical actions of parasitic secretions may also be involved. the infected gonads show altered structure and the gametogenic processes is aborted. there is no evidence of hemocytic response, but leucocite infiltration is evident at least in male infected gonads. an increased content of polysaccarides is evident in infected gonads.
Hermafroditismo Funcional de la Gónada de Fissurella crassa (Mollusca: Fissurellidae) Functional Hermaphrodite Gonad in Fissurella crassa (Mollusca: Fissurellidae)
Alberto Olivares Paz,David Jofré Madariaga,Carlos Alvarez Mazú,Eduardo Bustos-Obregón
International Journal of Morphology , 2009,
Abstract: La costa del Pacífico sudoriental es el hábitat de las 13 especies de lapas descritas del subgénero Fissurella Brugière. En estas especies no existe dimorfismo sexual, los animales son dioicos, el sexo se reconoce explorando directa o indirectamente las gónadas y no tienen procesos de reversión sexual. La presencia de un organismo de Fissurella crassa con gónada formada por porciones de ovario y otras de testículo con capacidad para generar óvulos y espermatozoides, evidencia la potencialidad que los organismos de Fissurella poseen para desarrollar el hermafroditismo funcional. Sin embargo, el presente hallazgo no permite inferir si el agente desencadenante del desarrollo sincrónico funcional de la gónada hermafrodita es un factor endógeno y/o asociado a algún evento exógeno medio ambiental. The coast of the Southeastern Pacific is the habitat for 13 species of described keyhole limpets of the subgenus Fissurella Brugière. In these species sexual dimorphism does not exist, the animals are dioicos, the sex is recognized exploring directly or indirectly the gonads and they do not have processes of sexual reversion. The presence of an organism Fissurella crassa with portions of ovary and testicle with ability to generate ova and sperms, demonstrates the potential that Fissurella's organisms possess to develop functional hermaphroditism. Nevertheless, the present find does not allow to infer if the trigger agent of the synchronous functional development of the hermaphrodite gonad is a factor endogenous and / or associated with any exogenous environmental event.
Hermafroditismo Funcional de la Gónada de Fissurella crassa (Mollusca: Fissurellidae)
Olivares Paz,Alberto; Jofré Madariaga,David; Alvarez Mazú,Carlos; Bustos-Obregón,Eduardo;
International Journal of Morphology , 2009, DOI: 10.4067/S0717-95022009000200034
Abstract: the coast of the southeastern pacific is the habitat for 13 species of described keyhole limpets of the subgenus fissurella brugière. in these species sexual dimorphism does not exist, the animals are dioicos, the sex is recognized exploring directly or indirectly the gonads and they do not have processes of sexual reversion. the presence of an organism fissurella crassa with portions of ovary and testicle with ability to generate ova and sperms, demonstrates the potential that fissurella's organisms possess to develop functional hermaphroditism. nevertheless, the present find does not allow to infer if the trigger agent of the synchronous functional development of the hermaphrodite gonad is a factor endogenous and / or associated with any exogenous environmental event.
Effects of the digenea Proctoeces lintoni (Fellodistomidae) in the proportion of hemolymphatic cells in Fissurella crassa (Mollusca: Archaeogastropoda)  [cached]
Oliva Marcelo E,Vásquez Ana M
Memórias do Instituto Oswaldo Cruz , 1999,
Abstract:
Filogenia molecular de las especies del subgénero Fissurella (Mollusca: Vetigastropoda) de la costa chilena
Olivares-Paz,Alberto; Quinteiro,Javier; Rey-Méndez,Manuel;
Revista de biología marina y oceanografía , 2011, DOI: 10.4067/S0718-19572011000300005
Abstract: several species of the genus fissurella coexist on the rocky intertidal substrate in the southeastern coast of the pacific ocean. thirteen species are considered as valid, considering some variable and morphologically unstable species, which have historically allowed registering 58 specific names. this report describes the congruence degree existing between the current typological classification and molecular data obtained from nuclear and mitochondrial genes. data includes sequences of the spacers its1 and its2 in the nuclear ribosomal operon and partial sequences of the mitochondrial gene nd1. reconstruction of phylogenetic relations shows congruence between mitochondrial and nuclear data and allows us to clearly establish two groups of species, including polyphyletic species. the first group contains the `latimarginata complex', which includes morphotypes of f. latimarginata, f. cumingi, f. bridgesii and f. oriens. in addition, the monophyletic species f. radiosa, f. pulchra and f. peruviana are included in this group. the second group corresponds to the complex `costata-picta' that includes f. costata and f. picta. other monophyletic species in this group were f. maxima in an intermediate position, f. limbata and f. nigra in a basal position. according to our results, f. crassa was situated in a basal position, i.e., close to root, within the phylogenetic tree. this data indicates the necessity of a taxonomic revision of this genus.
Chemical composition of the essential oil of Salvia limbata C. A. Mey
Seyed Ebrahim Sajjadi,Zahra Shahpiri
DARU : Journal of Pharmaceutical Sciences , 2004,
Abstract: The essential oil obtained by hydrodistillation of the aerial parts of Salvia limbata C.A. Mey. (Lamiaceae) was analyzed by GC/MS. Among the forty-two constituent, forty components were characterized representing 98.6% of the total component which were detected. Bicyclogermacrene (21.1%), α-pinene (15.5%), 1,8-cineole (11.0%), sabinene (10.6%), β-pinene (9.2%), spathulenol (8.2%), β-caryophyllene (5.3%) and δ-elemene (5.1%) were found to be the major constituents.
Sobre Ischnoplax pectinatus (Sowerby, 1840) e sua ocorrência no litoral sul do Brasil (Mollusca, Polyplacophora)
Guerra Júnior, Orlando;
Memórias do Instituto Oswaldo Cruz , 1985, DOI: 10.1590/S0074-02761985000400004
Abstract: new geographic records of ischnoplax pectinatus (sowerby, 1840) are pointed out on the south coast of brazil; its morphology and some biogeographic aspects are also studied.
Microscopic Anatomy of the Reproductive System in Two Sympatric Species of Fissurella Bruguiére, 1789 (Mollusca: Vetigastropoda)
Collado,Gonzalo A; Brown,Donald I;
International Journal of Morphology , 2007, DOI: 10.4067/S0717-95022007000200012
Abstract: this study describes the microscopic anatomy of the reproductive systems of the keyhole limpets fissurella latimarginata and fissurella cumingi to test the existence of a possible isolating reproductive mechanism of morphophysiological type between species, and consequently to determine if the findings provide a valid taxonomic characteristic to distinguish these sympatric species. the results show that in both species the reproductive system is intimately associated with the excretory system. the gonad has a septa organization, and is connected with the distal portion of the right kidney by means of a renopericardial duct which functions as a genital duct. the gametes are evacuated to the mantle cavity through the right kidney opening. besides transport of the gametes, the genital duct, which connects with the pericardium through the nephrostome, bears a gland attached to its inner wall both in males and females. no marked anatomical differences were noted between the reproductive systems of the two limpets which would allow their unequivocal taxonomic differentiation at the species level
Autentificación de lapas del género Fissurella (Mollusca: Vetigastropoda) en la costa chilena, mediante PCR-RFLP
Olivares-Paz,Alberto; Quinteiro,Javier; Rey-Méndez,Manuel;
Investigaciones marinas , 2006, DOI: 10.4067/S0717-71782006000100011
Abstract: keyhole limpets, belonging to the fissurella genus, have been harvested along the chilean coast since prehistoric times. exploited species show differences in tissue consistency and organoleptic features, and so are differently appreciated by consumers. the absence of morphological diagnostic characters in some food products elaborated using limpets, fraudulent commercial labeling or designation, and the overexploitation of this marine resource, suggest the need for a species identification methodology. the method would be a tool to guarantee the correct labeling of commercial products and for future fishery management purposes. a pcr-rflp protocol, using two restriction enzymes (hpych4 v and nla iii) allowed species identification within the fissurella genus along chilean coast, suggesting incongruence between classical taxonomy and genetic data. the specific restriction patterns are expected to be useful for species authentication in commercial products and for species identification in any phase of the life-cycle of fissurella species
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