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1.
Conserv Biol ; 37(1): e13965, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35686511

RESUMO

Ladybirds (Coleoptera: Coccinellidae) provide services that are critical to food production, and they fulfill an ecological role as a food source for predators. The richness, abundance, and distribution of ladybirds, however, are compromised by many anthropogenic threats. Meanwhile, a lack of knowledge of the conservation status of most species and the factors driving their population dynamics hinders the development and implementation of conservation strategies for ladybirds. We conducted a review of the literature on the ecology, diversity, and conservation of ladybirds to identify their key ecological threats. Ladybird populations are most affected by climate factors, landscape composition, and biological invasions. We suggest mitigating actions for ladybird conservation and recovery. Short-term actions include citizen science programs and education, protective measures for habitat recovery and threatened species, prevention of the introduction of non-native species, and the maintenance and restoration of natural areas and landscape heterogeneity. Mid-term actions involve the analysis of data from monitoring programs and insect collections to disentangle the effect of different threats to ladybird populations, understand habitat use by taxa on which there is limited knowledge, and quantify temporal trends of abundance, diversity, and biomass along a management-intensity gradient. Long-term actions include the development of a worldwide monitoring program based on standardized sampling to fill data gaps, increase explanatory power, streamline analyses, and facilitate global collaborations.


Las catarinas (Coleoptera: Coccinellidae) proporcionan servicios que son críticos para la producción de alimento, y juegan un papel ecológico como fuente de alimento para depredadores. Sin embargo, la riqueza, abundancia y distribución de catarinas están en peligro debido a muchas amenazas antropogénicas. La carencia de conocimiento sobre el estatus de conservación de la mayoría de las especies y los factores que inciden en su dinámica poblacional dificulta el desarrollo e implementación de estrategias de conservación para las catarinas. Realizamos una revisión de la literatura sobre la ecología, diversidad y conservación de catarinas para identificar sus amenazas ecológicas clave. Las poblaciones de catarinas fueron afectadas mayormente por factores climáticos, composición del paisaje e invasiones biológicas. Proponemos acciones de mitigación para la conservación y recuperación de catarinas. Acciones a corto plazo incluyen programas de ciencia y educación ciudadana, medidas de protección para la recuperación de hábitat y de especies amenazadas, prevención de la introducción de especies no nativas y el mantenimiento y restauración de áreas naturales y la heterogeneidad del paisaje. Acciones a mediano plazo implican el análisis de datos obtenidos de programas de monitoreo y colecciones de insectos para desenmarañar el efecto de las diferentes amenazas a las poblaciones de catarinas, comprender el uso del hábitat por taxa de los que se tiene conocimiento limitado y cuantifica las tendencias temporales de la abundancia, diversidad y biomasa a lo largo de un gradiente de intensidad de manejo. Acciones a largo plazo incluyen el desarrollo de un programa de monitoreo a nivel mundial basado en muestreos estandarizados para subsanar la falta de datos, incrementar el poder explicativo, optimizar los análisis y facilitar colaboraciones globales.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Animais , Espécies em Perigo de Extinção , Dinâmica Populacional
2.
Sci Rep ; 9(1): 847, 2019 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-30696916

RESUMO

Knowledge of Wolbachia prevalence with respect to its hosts is restricted mainly to taxonomic/phylogenetic context. In contrast, relations between infection and most host's ecological and biological traits are poorly understood. This study aimed to elaborate on relations between bacteria and its beetle hosts in taxonomic and the ecological contexts. In particular, the goal is to verify which ecological and biological traits of beetles could cause them to be prone to be infected. Verification of Wolbachia infection status across 297 beetle taxa showed that approximately 27% of taxa are infected by supergroups A and B. Only minor support for coevolution between bacteria and its beetle hosts was observed in some genera of beetles, but in general coevolution between beetles and Wolbachia was rejected. Some traits of beetles were found to be unrelated to Wolbachia prevalence (type of range and thermal preferences); some traits were related with ambiguous effects (habitats, distribution, mobility and body size); some were substantially related (reproduction mode and trophy). The aforementioned summary does not show obvious patterns of Wolbachia prevalence and diversity in relation to host taxonomy, biology, and ecology. As both Wolbachia and Coleoptera are diverse groups, this lack of clear patterns is probably a reflection of nature, which is characterised by highly diversified and probably unstable relations.


Assuntos
Infecções Bacterianas/imunologia , Besouros/imunologia , Wolbachia/fisiologia , Animais , Infecções Bacterianas/genética , Evolução Biológica , Ecossistema , Especificidade de Hospedeiro , Interações Hospedeiro-Patógeno , Reprodução , Simbiose
3.
Folia Biol (Krakow) ; 61(3-4): 177-83, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24279166

RESUMO

The structure of the karyotypes of two Otiorhynchus species belonging to separate subgenera, viz. Otiorhynchus s.str. bisulcatus and O. (Zadrehus) atroapterus, is compared and described for the first time. Both species have the same chromosome number (2n = 22), sex chromosome system of an achiasmate parachute type (Xy(p)), symmetric karyotype with the prevalence of metacentrics, similar meiotic behaviour, localization of NORs and positive DAPI signals. The main differences involve the morphology of autosomes and the X chromosome in the C-banding pattern and DAPI/CMA3 signals as well as in the presence of additional B chromosomes.


Assuntos
Análise Citogenética/métodos , Cariotipagem/métodos , Gorgulhos/genética , Animais , Cromossomos , Cariótipo
4.
Folia Biol (Krakow) ; 60(3-4): 129-33, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23342906

RESUMO

The karyotype structure of Protocalliphora falcozi is described for the first time. The diploid complement comprises 2n = 12, n(male) = 5+XY. Male mitotic plates include four pairs of long (metacentric) and one pair of medium-sized (submetacentric) autosomes. The submetacentric sex chromosomes X and Y are the smallest elements of the set. An achiasmatic meiosis was determined. The heterochromosomes do not form a heterovalent because they occur separately during the first meiotic division. The examined karyotype shows a pericentromeric position of constitutive heterochromatin in all autosomes. The longer arm of the X chromosome is heterochromatic, while the Y is entirely euchromatic. The NORs are active at mitotic prophase and at early meiotic stages. Small, bright signals were observed in the centromeric regions of autosomes after DAPI staining.


Assuntos
Dípteros/genética , Cariótipo , Animais , Feminino , Cariotipagem/métodos , Masculino
5.
Micron ; 40(8): 881-5, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19595603

RESUMO

We investigated the cytological mechanism of parthenogenesis by analyzing the chromosomes in five weevil species. All examined species are polyploids, four of which: Otiorhynchus ovatus, Simo variegates, Cathormiocerus aristatus, and Tropiphorus elevatus possess three haploid sets of chromosomes (3n=33), whereas the fifth, Trachyphloeus parallelus, is tetraploid with 44 chromosomes (4n=44). The plates contained 27-31 chromosomes in triploid species and 38, 39, 41 and even 44 in tetraploid T. parallelus. In all species single clusters of metaphase plates with a haploid number of n=11 were visible. Some oogonial cells showed nuclei configurations resembling the stages of diplotene and diakinesis. The spiralized chromosomes in these nuclei may have been connected by chiasmata resulting in rods figures and ring-shaped bivalents. Occurrence of the remnants of meiosis could suggest some degree of recombination in parthenogenetic lineages of weevils.


Assuntos
Meiose , Partenogênese , Prófase , Gorgulhos/citologia , Gorgulhos/fisiologia , Animais , Cromossomos/metabolismo , Cromossomos/ultraestrutura , Cariotipagem
6.
Folia Biol (Krakow) ; 56(1-2): 25-9, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19055021

RESUMO

Karyotypes of three weevil species, viz. Brachysomus dispar (2n=22, n males = 10 + X(y(p))), Brachysomus hirtus (3n=33, n females = 10 + X) and Strophosoma faber (2n=22, n males = 10 + X(y(p))) belonging to the tribes Sciaphilini and Brachyderini, were studied using the C-banding technique. The karyotype structures of the two bisexual and one parthenogenetic species are described for the first time. Most chromosomes are meta- or submetacentric. In the two species of the genus Brachysomus, the chromosomes resemble one another in having a rather small amount of heterochromatin restricted to the pericentromeric region, visible as dark stained blocks mainly during the early stages of nuclear division. Larger bands at mitotic metaphase and diakinesis occur only in Strophosomafaber. Geographic parthenogenesis in Brachysomus hirtus is briefly discussed.


Assuntos
Cromossomos/genética , Gorgulhos/genética , Animais , Bandeamento Cromossômico , Cariotipagem , Especificidade da Espécie
7.
Folia Biol (Krakow) ; 56(3-4): 213-7, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19055050

RESUMO

The karyotype structure of Laena reitteri is described for the first time. The chromosome number 2n = 18+1-3B and meioformula n(male) = 8+Xy+1-3B deviates from the modal tenebrionid number. The karyotype exhibits low variation in morphology and length. The diploid set consists of four long (subtelocentric and acrocentric), twelve medium-sized acrocentric autosomes and sex heterochromosomes Xy. The X chromosome is submetacentric, while the y is acrocentric and the smallest element of the set. On mitotic and meiotic plates 1-3 small additional elements are also visible, and probably represent B-chromosomes. The NORs are very active at mitotic prophase and early meiotic stages.


Assuntos
Cromossomos/genética , Besouros/genética , Animais , Cariotipagem , Especificidade da Espécie
8.
Genetica ; 134(2): 235-42, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18040867

RESUMO

Parthenogenesis and, in particular, polyploidy are rare in animals. A number of cases, known among weevils, represent apomictic parthenogenesis--a reproductive mode in which eggs undergo one maturation division, the chromosomes divide equationally, and no reduction takes place. Among parthenogenetic weevils there are two diploids, 48 triploids, 18 tetraploids, six pentaploids, three hexaploids and one decaploid. Eight examined parthenogenetic species are triploids with 33 chromosomes of different morphology, confirming that triploidy is the most common level of ploidy in weevils. The karyotypes are heterogeneous with the presence of meta-, submeta-, subtelo- and acrocentric chromosomes. The C-banding method showed that only two species possess a large amount of heterochromatin visible as a band around the centromere during mitotic metaphase. This agrees with observations that weevils are characterized by a small amount of heterochromatin, undetectable in metaphase plates after C-banding. In three species an atypical course of apomictic oogenesis occurs with stages similar to meiosis, in which chromosomes form bivalents and multivalent clusters. This association of chromosomes probably represents the remnants of meiosis, although these events have nothing to do with recombination. The results support the hypothesis that the evolution of apomictic parthenogenesis in weevils has proceeded through a stage of automixis.


Assuntos
Cromossomos/ultraestrutura , Partenogênese/genética , Gorgulhos/genética , Animais , Bandeamento Cromossômico , Feminino , Cariotipagem , Masculino , Poliploidia , Gorgulhos/citologia , Gorgulhos/fisiologia
9.
Folia Biol (Krakow) ; 54(1-2): 13-7, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17044254

RESUMO

Karyotypes of three species, Brachyderes incanus, Brachysomus setiger and Paophilus afflatus, belonging to the tribe Brachyderini, were studied using C-banding technique. The species share the same chromosome number 2n = 22 and meioformula n = 10+Xy(p) at all metaphase 1 plates of spermatid division. Some differences between karyotypes were observed in terms of centromere positions and C-band sizes. Most chromosomes are meta- or submetacentric and form a graded series in respect to length. The chromosomes resemble one another in having a rather small amount of heterochromatin restricted to the pericentromeric region and visible as dark stained blocks mainly during early stages of nuclear division. Only in Brachyderes incanus do larger bands occur at mitotic metaphase and diakinesis. These cytogenetic data are in agreement with karyological findings obtained in other species of Brachyderini so far examined.


Assuntos
Gorgulhos/classificação , Gorgulhos/genética , Animais , Cromossomos/genética , Feminino , Cariotipagem , Masculino , Especificidade da Espécie
10.
Folia Biol (Krakow) ; 53(1-2): 65-8, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16212110

RESUMO

B-chromosomes were observed in spermatogonial mitotic metaphases, meiotic metaphases I and II of Barpeithes pellucidus from one population in Slovakia. The number of B-chromosomes ranged from one to six per cell and they paired with the sex heterochromosomes in the first meiotic metaphase and rarely with the autosomes. In metaphase I one B-chromosome was always associated with X chromosome forming a tripartite complex. The XyBp was easily recognizable as a complex of three chromosomes in a parachute association The size of the B-chromosomes was approximately the same or a little smaller than that of the y heterochromosome which was the smallest element of the regular chromosome set. Their staining intensity seems to be similar to that of the autosomes and sex chromosomes, respectively. The behaviour of B-chromosomes during mitosis and meiosis in weevils is briefly discussed.


Assuntos
Cromossomos , Besouros/genética , Animais , Europa (Continente) , Cariotipagem
11.
Folia Biol (Krakow) ; 52(1-2): 61-6, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15521650

RESUMO

Chromosome numbers and C-banding patterns of sixteen weevil species are presented. The obtained results confirm the existence of two groups of species with either a small or large amount of heterochromatin in the karyotype. The first group comprises twelve species (Apionidae: Oxystoma cerdo, Eutrichapion melancholicum, Ceratapion penetrans, Ceratapion austriacum, Squamapion flavimanum, Rhopalapion longirostre; Nanophyidae: Nanophyes marmoratus; Curculionidae: Centricnemus (=Peritelus) leucogrammus, Sitona humeralis, Sitona lineatus, Sitona macularis, Sitona suturalis). In weevils with a small amount of heterochromatin, tiny grains on the nucleus during interphase are visible, afterwards appearing as dark dots during mitotic and meiotic prophase. The second group comprises four species from the curculionid subfamily Cryptorhynchinae (Acalles camelus, Acalles commutatus, Acalles echinatus, Ruteria hypocrita) which possess much larger heteropycnotic chromosome parts visible during all nuclear divisions. The species examined have pericentromeric C-bands on autosomes and on the X chromosome.


Assuntos
Cromossomos/genética , Gorgulhos/genética , Animais , Bandeamento Cromossômico , Heterocromatina/genética , Cariotipagem , Polônia , Eslováquia , Especificidade da Espécie
12.
Folia Biol (Krakow) ; 50(1-2): 9-12, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12597526

RESUMO

Karyotypic details were studied in males of six beetle species from three families, viz. Tenebrionidae: Dailognatha pumila Bdy. (2n = 20, n(male) = 9 + Xy(p)), Pachyscelis musiva Ménétr. (2n = 18, n(male) = 8 + Xy(p)), Pimelia capito Kryn. (2n = 18, n(male) = 8 + Xy(p)); Cerambycidae: Agapanthia walteri Reitt. (2n = 20, n(male) = 9+Xy(p)), Agapanthia korostelevi Danilevsky (2n = 20, n(male) = 9 + Xy(p)); Curculionidae: Phyllobius caucasicus Stierl. (2n = 22, n(male) = 10 + Xy(p)). The chromosome number and sex determining system of all beetle species are described for the first time. Evolutionary trends in karyotypes of the studied beetle groups are briefly discussed.


Assuntos
Cromossomos/genética , Besouros/genética , Animais , Armênia , Feminino , Cariotipagem , Masculino , Processos de Determinação Sexual
13.
Folia Biol (Krakow) ; 50(1-2): 17-21, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12597528

RESUMO

C-banded karyotypes were studied in the males of seven ladybird species from the subfamily Coccinellinae, viz. Adonia variegata (Goeze), Tythaspis sedecimpunctata (L.), Coccinella septempunctata (L.), Calvia decemguttata (L.), Calvia quatuordecimguttata (L.), Propylea quatuordecimpunctata (L.), Phyllobora vigintiduopunctata (L.). All the species, with the exception of Tythaspis sedecimpunctata (L.), possess 2n = 20, n(male) = 9 + Xy(p). Tythaspis sedecimpunctata (L.), however, has 2n = 24, n(male) = 11+Xy. The examined karyotypes show only a paracentromeric position of constitutive heterochromatin in all autosomes and the sex chromosome X, while the y heterochromosome is dot-like and wholly euchromatic. Successive stages of spermiogenesis were analysed.


Assuntos
Cromossomos/genética , Besouros/classificação , Besouros/genética , Espermatozoides , Animais , Bandeamento Cromossômico , Europa (Continente) , Marcadores Genéticos , Cariotipagem , Masculino , Meiose , Especificidade da Espécie
14.
Folia Biol (Krakow) ; 50(3-4): 129-34, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12729158

RESUMO

The C-banding patterns of twelve weevil species are presented. The obtained results confirm the existence of two groups of species: with a small or large amount of heterochromatin in the karyotype. The first group comprises seven species (Apionidae: Holotrichapion pisi; Curculionidae: Phyllobius urticae, Ph. pyri, Ph. maculicornis, Tanymecus palliatus, Larinodontes turbinatus, Cionus tuberculosus). In weevils with a small amount of heterochromatin, tiny grains on the nucleus in interphase are visible, afterwards in mitotic and meiotic prophase appearing as dark dots. The absence of C-bands does not indicate a lack of heterochromatin but heterochromatic regions are sometimes so small that the condensation is not visible during the cell cycle. The second group comprises five species (Otiorhynchus niger, O. morio, Polydrusus corruscus, Barypeithes chevrolati, Nedyus quadrimaculatus) which possess much larger heteropicnotic parts of chromosomes visible during all nuclear divisions. The species examined have paracentromeric C-bands on autosomes and the sex chromosome X, except for Otiorhynchus niger, which also has an intercalary bands on one pair of autososomes. All the species examined differ in the size of segments of constitutive heterochromatin. The y heterochromosome is dot-like and wholly euchromatic in all the studied species.


Assuntos
Bandeamento Cromossômico , Cromossomos , Besouros/classificação , Besouros/genética , Animais , Cromossomos/classificação , Eucromatina/classificação , Feminino , Heterocromatina/classificação , Masculino , Especificidade da Espécie
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