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1.
Int J Food Microbiol ; 343: 109094, 2021 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-33621832

RESUMO

Anisakid nematode larvae (NL) in fish products comprise a risk to human health and, if visible, lead to the rejection of these products by consumers. Therefore, great efforts are being made for the identification of these anisakid larvae to estimate the potential consumer health risk as well as to develop effective detection methods in order to prevent the introduction of heavily infected fish products into the market. The tasks of national reference laboratories include the improvement of detection methods and to promote their further development. As a prerequisite for improved detection, it is important to understand the structural properties of anisakid NL and compounds produced during host-parasite interactions. This review provides an overview of the intrinsic properties of anisakid NL and reports the latest detection methods in published literature. First, in order to define the potentially interesting intrinsic properties of anisakid nematodes for their detection, anatomy and compounds involved in host-parasite interactions are summarised. These can be used for various detection approaches, such as in the medical field or for allergen detection in fish products. In addition, fluorescence characteristics and their use as both established and promising candidates for detection methods, especially in the field of optical sensing technologies, are presented. Finally, different detection and identification methods applied by the fish processing industries and by control laboratories are listed. The review intends to highlight trends and provide suggestions for the development of improved detection and identification methods of anisakid NL in fish products.


Assuntos
Anisakis/isolamento & purificação , Produtos Pesqueiros/parasitologia , Microbiologia de Alimentos , Animais , Anisaquíase/parasitologia , Anisaquíase/prevenção & controle , Anisakis/anatomia & histologia , Anisakis/química , Produtos Pesqueiros/análise , Fluorescência , Indústria de Processamento de Alimentos , Interações Hospedeiro-Parasita , Humanos , Larva/anatomia & histologia , Larva/química
2.
Nat Commun ; 12(1): 1118, 2021 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-33602914

RESUMO

Modern biomedical research and preclinical pharmaceutical development rely heavily on the phenotyping of small vertebrate models for various diseases prior to human testing. In this article, we demonstrate an acoustofluidic rotational tweezing platform that enables contactless, high-speed, 3D multispectral imaging and digital reconstruction of zebrafish larvae for quantitative phenotypic analysis. The acoustic-induced polarized vortex streaming achieves contactless and rapid (~1 s/rotation) rotation of zebrafish larvae. This enables multispectral imaging of the zebrafish body and internal organs from different viewing perspectives. Moreover, we develop a 3D reconstruction pipeline that yields accurate 3D models based on the multi-view images for quantitative evaluation of basic morphological characteristics and advanced combinations of metrics. With its contactless nature and advantages in speed and automation, our acoustofluidic rotational tweezing system has the potential to be a valuable asset in numerous fields, especially for developmental biology, small molecule screening in biochemistry, and pre-clinical drug development in pharmacology.


Assuntos
Acústica , Rotação , Peixe-Zebra/anatomia & histologia , Animais , Etanol/farmacologia , Imageamento Tridimensional , Larva/anatomia & histologia , Larva/efeitos dos fármacos , Fígado/anatomia & histologia , Fígado/efeitos dos fármacos , Tamanho do Órgão/efeitos dos fármacos , Fenótipo , Transdutores
3.
PLoS One ; 15(9): e0236653, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32956411

RESUMO

Symbiosis can facilitate the development of specialized organs in the host body to maintain relationships with beneficial microorganisms. To understand the developmental and genetic mechanisms by which such organs develop, it is critical to first investigate the morphology and developmental timing of these structures during the onset of host development. We utilized micro-computed tomography (µCT) to describe the morphology and development of mycangia, a specialized organ, in the Asian ambrosia beetle species Euwallacea validus which maintains a mutualistic relationship with the Ascomycete fungus, Fusarium oligoseptatum. We scanned animals in larval, pupal and adult life stages and identified that mycangia develop during the late pupal stage. Here we reconcile preliminary evidence and provide additional morphological data for a second paired set of structures, including the superior, medial mycangia and an inferior, lateral pair of pouch-like structures, in both late-stage pupae and adult female beetles. Furthermore, we report the possible development of rudimentary, or partially developed pairs of medial mycangia in adult male beetles which has never been reported for any male Xyleborini. Our results illustrate the validity of µCT in observing soft tissues and the complex nature of mycangia morphology and development.


Assuntos
Besouros/crescimento & desenvolvimento , Besouros/ultraestrutura , Animais , Besouros/anatomia & histologia , Feminino , Larva/anatomia & histologia , Larva/crescimento & desenvolvimento , Larva/ultraestrutura , Masculino , Pupa/anatomia & histologia , Pupa/crescimento & desenvolvimento , Pupa/ultraestrutura , Caracteres Sexuais , Microtomografia por Raio-X
4.
PLoS Biol ; 18(9): e3000828, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32936797

RESUMO

Many herbivorous insects are mono- or oligophagous, having evolved to select a limited range of host plants. They specifically identify host-plant leaves using their keen sense of taste. Plant secondary metabolites and sugars are thought to be key chemical cues that enable insects to identify host plants and evaluate their quality as food. However, the neuronal and behavioral mechanisms of host-plant recognition are poorly understood. Here, we report a two-factor host acceptance system in larvae of the silkworm Bombyx mori, a specialist on several mulberry species. The first step is controlled by a chemosensory organ, the maxillary palp (MP). During palpation at the leaf edge, the MP detects trace amounts of leaf-surface compounds, which enables host-plant recognition without biting. Chemosensory neurons in the MP are tuned with ultrahigh sensitivity (thresholds of attomolar to femtomolar) to chlorogenic acid (CGA), quercetin glycosides, and ß-sitosterol (ßsito). Only if these 3 compounds are detected does the larva make a test bite, which is evaluated in the second step. Low-sensitivity neurons in another chemosensory organ, the maxillary galea (MG), mainly detect sucrose in the leaf sap exuded by test biting, allowing larvae to accept the leaf and proceed to persistent biting (feeding). The two-factor host acceptance system reported here may commonly underlie stereotyped feeding behavior in many phytophagous insects and determine their feeding habits.


Assuntos
Bombyx/fisiologia , Comportamento de Escolha , Dieta , Comportamento Alimentar/fisiologia , Larva/fisiologia , Papilas Gustativas/fisiologia , Fenômenos Fisiológicos da Nutrição Animal , Animais , Comportamento Animal/fisiologia , Bombyx/anatomia & histologia , Bombyx/crescimento & desenvolvimento , Células Quimiorreceptoras/fisiologia , Quimiotaxia/fisiologia , Sinais (Psicologia) , Comportamento Exploratório/fisiologia , Interações Hospedeiro-Parasita/fisiologia , Larva/anatomia & histologia , Larva/citologia , Morus/química , Folhas de Planta/química , Paladar/fisiologia , Papilas Gustativas/anatomia & histologia
5.
Parasitol Res ; 119(10): 3359-3368, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32893331

RESUMO

Acanthocephalans are multi-host endoparasites, many of which use freshwater amphipods as intermediate hosts for their larval stages (e.g., cystacanths) while adults live in the intestines of vertebrates, including waterfowl. In central Alberta, Canada, several co-occurring species of the acanthocephalan genus Polymorphus use the amphipod Gammarus lacustris Sars, 1863 as an intermediate host. We applied DNA barcoding and morphometric analysis to differentiate cystacanth larvae from G. lacustris sampled from 17 Albertan water bodies. We slide-mounted specimens and measured morphological traits relating to proboscis hooks. We sequenced the standard DNA barcoding region of the mitochondrial cytochrome c oxidase subunit I gene (COI). Morphometric analysis suggested that the acanthocephalans we collected belonged to four morphologically different groups that keyed to Polymorphus contortus (Bremser, 1821) Travassos, 1926; P. marilis Van Cleave, 1939; P. paradoxus Connel et Corner, 1957; and P. strumosoides (Lundström, 1942) Amin, 2013. Our Bayesian tree based on COI sequences generally corroborated the morphological results and supported that the specimens assigned to P. cf. contortus and P. cf. strumosoides belong to two distinct species. In contrast, the Bayesian tree showed that specimens of P. cf. marilis were nested as a cluster within the P. cf. paradoxus clade. Similarly, small pairwise genetic distance (< 2%) between specimens identified as P. cf. contortus and P. cf. strumosoides suggests that they are conspecific. Future studies should use morphology and sequence data from adult acanthocephalans to assess the taxonomic identity of the cystacanth-based Polymorphus taxa. Our study is the first to provide genetic information for the four Polymorphus taxa and emphasizes the importance of applying multiple approaches to differentiate parasite species.


Assuntos
Acantocéfalos/classificação , Acantocéfalos/anatomia & histologia , Acantocéfalos/genética , Alberta , Anfípodes/parasitologia , Animais , Código de Barras de DNA Taxonômico , Água Doce/parasitologia , Genes de Helmintos/genética , Genes Mitocondriais/genética , Larva/anatomia & histologia , Larva/classificação , Larva/genética , Especificidade da Espécie
6.
Korean J Parasitol ; 58(4): 467-473, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32871642

RESUMO

Chinese edible frogs, Hoplobatrachus rugulosus, were examined to estimate the potential risks of human gnathostomiasis and sparganosis in Myanmar. A total of 20 frogs were purchased in a local market of Yangon and examined with naked eyes and the artificial digestion method after skin peeling in June 2018 and June 2019. Larvae of gnathostomes and Spirometra (=spargana) were detected in 15 (75.0%) and 15 (75.0%) frogs with average intensities of 10.5 and 6.3 larvae per infected frog, respectively. Gnathostome larvae were 2.75-3.80 (av. 3.30) mm long and 0.29-0.36 (0.33) mm wide. They had a characteristic head bulb with 4 rows of hooklets, a muscular long esophagus, and 2 pairs of cervical sac. The mean number of hooklets were 41, 44, 47, and 50 on the 1st, 2nd, 3rd, and 4th row, respectively. Collected spargana were actively moving, particularly with the scolex part, and have ivory-white color and variable in size. Conclusively, it has been first confirmed that Chinese edible frogs, H. rugulosus, are highly infected with larval gnathostomes and spargana in this study. Consuming these frogs is considered a potential risk of human gnathostomiasis and sparganosis in Myanmar.


Assuntos
Anuros/parasitologia , Gnathostoma/isolamento & purificação , Larva , Animais , Parasitologia de Alimentos , Gnathostoma/anatomia & histologia , Gnatostomíase/parasitologia , Larva/anatomia & histologia , Mianmar , Risco
7.
Proc Biol Sci ; 287(1933): 20201474, 2020 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-32811310

RESUMO

The majority of animal species have complex life cycles, in which larval stages may have very different morphologies and ecologies relative to adults. Anurans (frogs) provide a particularly striking example. However, the extent to which larval and adult morphologies (e.g. body size) are correlated among species has not been broadly tested in any major group. Recent studies have suggested that larval and adult morphology are evolutionarily decoupled in frogs, but focused within families and did not compare the evolution of body sizes. Here, we test for correlated evolution of adult and larval body size across 542 species from 42 families, including most families with a tadpole stage. We find strong phylogenetic signal in larval and adult body sizes, and find that both traits are significantly and positively related across frogs. However, this relationship varies dramatically among clades, from strongly positive to weakly negative. Furthermore, rates of evolution for both variables are largely decoupled among clades. Thus, some clades have high rates of adult body-size evolution but low rates in tadpole body size (and vice versa). Overall, we show for the first time that body sizes are generally related between adult and larval stages across a major group, even as evolutionary rates of larval and adult size are largely decoupled among species and clades.


Assuntos
Anuros/anatomia & histologia , Tamanho Corporal , Animais , Evolução Biológica , Larva/anatomia & histologia , Fenótipo , Filogenia
8.
Parasitol Res ; 119(10): 3285-3296, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32812144

RESUMO

The taxonomy of Hysterothylacium genus in Mediterranean waters remains incomplete and unresolved. The aim of the current study was to investigate the morphological and molecular identification of selected species of Hysterothylacium larvae in marine fish from the Tunisian Mediterranean coasts. A total of 192 marine fish samples were examined. In total, thirty-seven third-stage larvae of Hysterothylacium were morphologically identified as Hysterothylacium type V. In the present study, representatives of this type from the Mediterranean Sea were genetically characterized for the first time by sequencing the rDNA ITS (ITS1-5.8S-ITS2) regions and mtDNA cox2 gene. This study represents the first report of Hysterothylacium type V from the Mediterranean Sea. We also report Mullus barbatus, M. surmuletus, and Pagellus erythrinus as new hosts for this larval type. Based upon molecular and phylogenetic analyses considering the rDNA ITS regions, the Hysterothylacium type V described here was classified as a new genotype, named Genotype B. The valid genetic data of the described Hysterothylacium type V in the present study can be used to establish the phylogenetic relationships among Hysterothylacium species from the Mediterranean Sea and worldwide for future research.


Assuntos
Infecções por Ascaridida/veterinária , Ascaridoidea/classificação , Ascaridoidea/crescimento & desenvolvimento , Doenças dos Peixes/parasitologia , Peixes/parasitologia , Animais , Infecções por Ascaridida/parasitologia , Ascaridoidea/anatomia & histologia , Ascaridoidea/genética , DNA Mitocondrial/genética , DNA Espaçador Ribossômico/genética , Peixes/classificação , Genes de Helmintos/genética , Genótipo , Larva/anatomia & histologia , Larva/classificação , Larva/genética , Larva/crescimento & desenvolvimento , Mar Mediterrâneo , Filogenia
9.
Rev Bras Parasitol Vet ; 29(2): e000420, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32609238

RESUMO

Angiostrongylus vasorum is a pulmonary artery parasite of domestic and wild canid. On molluscs, intermediate host, first stage larvae (L1) are found after the first day of infection, in the 8th L2 and in the 30 th L3. It was evaluated L1, L2 and L3 recovered by Baermann technique from Achatina fulica infected with 1000 L1. Fifty larvae/stage were incubated with antibodies anti-ß-tubulin, anti-α-tubulin, anti- α-actin, anti-ß-actin and anti-collagen, and then with Alexa 633. Fifty larvae/stage were observed with picrosirius red and Oil Red O. It was also observed in the anterior region of L1 the beginning of the chitinous stems development, in the initial portion of the intestine and genital primordium. In L2 anterior region, the papillae, chitinous canes juxtaposed to the mouth and intestines bigger than L1. The L3 musculature is well defined, next to the chitinous stems, there are two round distally arranged from each other. It was observed the whole extension of the intestine genital primordium and intense cellularity in the L3 distal portion. With the picrosirius red the L1, L2 and L3 musculature could be observed, as the nerve ganglia on L3. Oil Red O revealed that L1, L2 and L3 store energy on lipid droplets.


Assuntos
Angiostrongylus , Gastrópodes , Parasitologia , Angiostrongylus/anatomia & histologia , Animais , Gastrópodes/parasitologia , Larva/anatomia & histologia , Parasitologia/métodos
10.
BMC Evol Biol ; 20(1): 79, 2020 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-32600301

RESUMO

BACKGROUND: Metamorphosis remains one of the most complicated and poorly understood processes in insects. This is particularly so for the very dynamic transformations that take place within the pupal sheath of holometabolous insects. Only few studies address these transformations especially with regard to cranial structures of those holometabolous species where the larval and adult forms have a similar diet. It thus remains unclear to what extent the internal structures undergo histolysis and rebuilding. Here, the development of the brain and skeleto-muscular system of the head of Chrysopa pallens (Rambur, 1838) is studied. This species is a predator of aphids in the larval and adult stage. RESULTS: We used micro-computed-tomography (µ-CT) to study the transformations of the larval, prepupal and pupal head within the cocoon. We first assessed the morphological differences and similarities between the stages. We then determined the point in time when the compound eyes appear and describe the re-orientation of the head capsule which transforms the prognathous larva into a hypognathous adult. The internal head muscles are distinctly more slender in larvae than adults. In addition, the adults have a significantly larger brain which is likely needed for the processing of the signals obtained by the adults vastly expanded sensory organs that are presumably needed for dispersal and mating. Our study shows that the histolysis and modification of the inner muscles and skeletal elements take place within the prepupa. The central nervous system persists throughout metamorphosis but its morphology changes significantly. CONCLUSION: Our study reveals that not only the inner structures, but also the outer morphology continues to change after the final larval moult. The adult cuticle and internal structures form gradually within the cocoon. The histolysis and rebuilding begin with the skeletal elements and is followed by changes in the central nervous system before it concludes with modifications of the musculature. This order of events is likely ancestral for Holometabola because it is also known from Hymenoptera, Diptera, Mecoptera, and Coleoptera.


Assuntos
Evolução Biológica , Cabeça/anatomia & histologia , Insetos/anatomia & histologia , Insetos/crescimento & desenvolvimento , Metamorfose Biológica , Animais , Cabeça/diagnóstico por imagem , Imageamento Tridimensional , Larva/anatomia & histologia , Larva/crescimento & desenvolvimento , Músculos/anatomia & histologia , Pupa/anatomia & histologia , Pupa/crescimento & desenvolvimento , Tomografia Computadorizada por Raios X
11.
PLoS One ; 15(6): e0234299, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32579561

RESUMO

While comparatively few amphibian species have been described on the North East Asian mainland in the last decades, several species have been the subject of taxonomical debates in relation to the Yellow sea. Here, we sampled Dryophytes sp. treefrogs from the Republic of Korea, the Democratic People's Republic of Korea and the People's Republic of China to clarify the status of this clade around the Yellow sea and determine the impact of sea level change on treefrogs' phylogenetic relationships. Based on genetics, call properties, adult morphology, tadpole morphology and niche modelling, we determined the segregated status species of D. suweonensis and D. immaculatus. We then proceeded to describe a new treefrog species, D. flaviventris sp. nov., from the central lowlands of the Republic of Korea. The new species is geographically segregated from D. suweonensis by the Chilgap mountain range and known to occur only in the area of Buyeo, Nonsan and Iksan in the Republic of Korea. While the Yellow sea is the principal element to the current isolation of the three clades, the paleorivers of the Yellow sea basin are likely to have been the major factor for the divergences within this clade. We recommend conducting rapid conservation assessments as these species are present on very narrow and declining ranges.


Assuntos
Anuros/classificação , Anuros/genética , Oceanos e Mares , Migração Animal , Animais , Anuros/anatomia & histologia , Ásia , Larva/anatomia & histologia , Filogenia , Dinâmica Populacional
12.
Arthropod Struct Dev ; 56: 100932, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32375099

RESUMO

Endoparasitic larval stages of Eoxenos laboulbenei were documented with different techniques, with a main focus on the male tertiary larva. Two discrete endoparasitic stages occur, the secondary and the tertiary larva. The presence of large compound eyes and externally visible wing buds in the tertiary larva is a unique feature within Holometabola. The brain with large optic lobes is followed by a single postcephalic ganglionic complex. The cephalic musculature is greatly reduced but pharyngeal dilators and muscles associated with the mouth field are present. Postcephalic sclerites are absent except for the pronotum. The segmented legs bear filiform pretarsal claws. The indirect flight muscles fill up a large part of the metathorax. The 10-segmented abdomen lacks appendages. Pleural folds are present on the thorax and abdomen. The digestive tract is characterized by a very short oesophagus. The large midgut and the narrow hindgut are disconnected. Six short Malpighian tubules are present. Large testes fill out almost the entire abdomen. In contrast to the tertiary larva, the muscles of the secondary larva are not fully differentiated. Cephalic appendages are present as bud-shaped anlagen. The legs lack a pretarsal claw. The developmental transformations are outlined and discussed, also with respect to phylogenetic implications.


Assuntos
Holometábolos/anatomia & histologia , Animais , Croácia , Feminino , Holometábolos/crescimento & desenvolvimento , Larva/anatomia & histologia , Larva/crescimento & desenvolvimento , Masculino
13.
Zoolog Sci ; 37(2): 193-202, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32282150

RESUMO

The Japanese wrinkled frog Glandirana rugosa is separated into five genetically different groups. One group in western Japan is further divided into three subgroups, found in Kyushu, Shikoku, and western Honshu. We collected G. rugosa frogs at 39 sites in Kyushu and determined nucleotide sequences of the mitochondrial 12S and 16S rRNA genes for phylogenetic analysis. Unexpectedly, we found a group of frogs in southeastern Kyushu that did not cluster with any of the pre-existing five groups of G. rugosa on the phylogenetic trees. The frogs in the new group and G. rugosa in Kyushu were externally similar, but there were a few significant differences in morphological features between the two populations. In addition, we observed significant differences in the frogs' calls . Thus, the group of the frogs in southeastern Kyushu may represent a new candidate species in the genus Glandirana. We discuss the possibility of a new species.


Assuntos
Ranidae/classificação , Ranidae/genética , Animais , DNA Mitocondrial/genética , Feminino , Japão , Larva/anatomia & histologia , Masculino , Filogenia , RNA Ribossômico 16S/genética , Ranidae/anatomia & histologia , Ranidae/crescimento & desenvolvimento , Análise de Sequência de DNA , Especificidade da Espécie , Vocalização Animal
14.
Arthropod Struct Dev ; 56: 100933, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32259775

RESUMO

Stick insects have elaborate mechanosensory organs in their subgenual organ complex in the proximal tibia, particularly the distal organ with scolopidial sensilla in linear arrangement. For early postembryonic developmental stages of Sipyloidea sipylus (Phasmatodea: Necrosciinae), the neuroanatomy of the scolopidial organs in the subgenual organ complex and the campaniform sensilla is documented by retrograde axonal tracing, and compared to the adult neuroanatomy. Already after hatching of the first larval instars are the sensory structures of subgenual organ and distal organ as well as tibial campaniform sensilla differentiated. In the distal organ, the full set of sensilla is shown in all larval stages examined. This finding indicates that the sensory organs differentiate during embryogenesis, and are already functional by the time of hatching. The constancy of distal organ sensilla over postembryonic stages allows investigation of the representative number of sensilla in adult animals as well as in larval instars. Some anatomical changes occur by postembryogenic length increase of the distal organ, and grouping of the anterior subgenual sensilla. The embryonic development of scolopidial sensilla is similar for auditory sensilla in hemimetabolous Orthoptera (locusts, bushcrickets, crickets) where tympanal membranes develop during postembryogenic stages, conferring a successive gain of sensitivity with larval moults.


Assuntos
Neópteros/crescimento & desenvolvimento , Animais , Larva/anatomia & histologia , Larva/crescimento & desenvolvimento , Microscopia , Neópteros/anatomia & histologia , Sistema Nervoso/anatomia & histologia , Sistema Nervoso/crescimento & desenvolvimento , Sensilas/anatomia & histologia , Sensilas/crescimento & desenvolvimento
15.
Chemosphere ; 250: 126287, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32135436

RESUMO

Glyphosate-based herbicide (GBH) using is increasing on a global scale. Few studies have investigated the sub-lethal effects of GBH in endemic amphibian species. The present work tested the GBH Roundup Active® on the tadpoles of Dendropsophus molitor. The exposure was in a range of plausible environmental concentrations (0-0.75 µg a.e./L) during a month. D. molitor is an endemic tropical frog of South America. The exposure from 325 µg a.e./L caused histological alterations in the liver. The high-resolution optical microscopy (HROM) detected sinusoidal dilatation and cytoplasmic vacuolization. The transmission electron microscopy (TEM) showed disorganization of the endoplasmic reticulum. Since the liver is essential for detoxification, these results suggest choric effects. Exposure to another GBH has caused histological alterations in liver tadpoles liver in a previous study, but, this study tested another endemic South-American frog for only 96h. The present work applied HROM to observe lipid alterations since it does not use organic solvents; and TEM for the ultrastructural observation of hepatocytes. Environmental risk of GBH can improve by including sub-lethal effects in endemic species.


Assuntos
Glicina/análogos & derivados , Larva/efeitos dos fármacos , Fígado/efeitos dos fármacos , Animais , Anuros/anatomia & histologia , Colômbia , Glicina/toxicidade , Herbicidas/toxicidade , Larva/anatomia & histologia , Fígado/anatomia & histologia , Fígado/patologia , Fígado/ultraestrutura , Microscopia/métodos , América do Sul
16.
Syst Parasitol ; 97(2): 201-215, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32078722

RESUMO

The soft tick Ornithodoros peruvianus Kohls, Clifford & Jones, 1969 was described as a parasite of bats in Peru upon the examination of engorged larvae only. Recently, larvae of this tick species were reported on bats from northern Chile. However, the adult and nymphal stages of O. peruvianus have remained undescribed. This study aimed to redescribe the larva of O. peruvianus based on unfed specimens, and to describe nymphs, the male and the female of this species. Ticks were collected on the walls inside three caves in northern Chile. Two females laid eggs in the laboratory. Part of the unfed larvae was separated for morphological and morphometrical analyses, and the remaining specimens were fed upon laboratory mice in order to obtain subsequent nymphal and adult stages. The first nymphal stage (N1) moulted either to male or to a second nymphal stage (N2) without feeding. Obtained N2 moulted either to male or female after one meal. PCR amplification of tick mitochondrial 16S rRNA of specimens from the three caves revealed almost identical sequences. The unfed larva of O. peruvianus has an elongated idiosoma, and fringed setae cover the ventral surfaces of coxae, palps and tarsi. Nymph 1 has a thin integument covered by incipient mammillae and barely noticeable dorsal disks; it lacks cheeks and possesses few short setae on the basis capitulum. Nymph 2 has a pair of small cheeks and resembles adult stages in its tegumentary traits and capitulum. Adult stages exhibit developed cheeks (larger in females) without the capacity to completely cover the capitulum. Very small and low mammillae cover the surface of the dorsal idiosoma in adults. As this feature also occurs in other bat-associated soft ticks, regardless of their phylogenetic relatedness, small mammillae in bat soft ticks are suggestive of convergent evolution.


Assuntos
Ornithodoros/classificação , Animais , Chile , DNA Ribossômico/genética , Feminino , Larva/anatomia & histologia , Masculino , Ninfa/anatomia & histologia , Ornithodoros/anatomia & histologia , Ornithodoros/genética , Peru , Especificidade da Espécie
17.
J Morphol ; 281(4-5): 465-475, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32092182

RESUMO

During the early ontogeny of fish larvae, the accurate development of the visual system plays a key role, because it is involved in locating food, orientation, selection of favorable habitat, and evasion of predators. The structure of the eye of the fish is typical of vertebrates, with some modifications related to the aquatic environment. In the present work, we describe the development of the larval eye of Engraulis anchoita for the first time. Larvae were collected at the Permanent Station of Environmental Studies (EPEA) in coastal waters of the Southwestern Atlantic Ocean during research cruises in 2015 and 2016. We describe the histology of the retina layers, determine the beginning of the functionality of the eye, and discuss a possible synchronization with the development of the digestive tract. This study provides information about the biology of E. anchoita, the most abundant fish species in the southwestern Atlantic Ocean. Also, recent studies have shown responses of the retina and other tissues to the increase in environmental acidity. Therefore, results of this study are also discussed with respect to the possible effect of acidification on the larvae of this species. The continuity of the time series developed at the EPEA will allow monitoring the effect of long-term environmental and biological variables on the early ontogeny of anchovy in the context of climate change. The high commercial fishing potential of E. anchoita due to its high abundance, as well as its essential role in the trophic web of other commercially valuable fishing resources of Argentina, reinforce the need to continue deepening knowledge about this species. Research highlights: Eyes of Engraulis anchoita larvae are functional from early larval stages. At hatching, the retina is formed by only few layers from which the other layers differentiates during ontogeny. Focal distance increases with larval growth.


Assuntos
Olho/anatomia & histologia , Olho/crescimento & desenvolvimento , Peixes/anatomia & histologia , Peixes/crescimento & desenvolvimento , Animais , Argentina , Ecossistema , Olho/citologia , Geografia , Larva/anatomia & histologia , Larva/crescimento & desenvolvimento , Retina/anatomia & histologia , Retina/citologia , Retina/crescimento & desenvolvimento
18.
Zoolog Sci ; 37(1): 91-101, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32068378

RESUMO

Two lineages of stream toads in the genus Ansonia from Malaysian Borneo have long been suspected to be specifically distinct on the basis of molecular data. We assessed the taxonomic status of these lineages using morphological and additional genetic data. In mtDNA phylogeny, each lineage-one from Bario, Kelabit Highlands of Sarawak, the other from Mt. Mulu of Sarawak and the Crocker Range of Sabah-is separated from other congeners by large genetic distances, comparable with those observed between heterospecific species in the genus. These lineages are also morphologically distinguishable from other species, and are considered to represent valid, independently evolving species. We therefore describe them as A. kelabitensis sp. nov. and A. kanak sp. nov.


Assuntos
Bufonidae/anatomia & histologia , Bufonidae/classificação , Animais , Bornéu , Bufonidae/genética , Bufonidae/crescimento & desenvolvimento , DNA Mitocondrial/genética , Feminino , Larva/anatomia & histologia , Masculino , Filogenia , Especificidade da Espécie
19.
PLoS One ; 15(2): e0227853, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32023290

RESUMO

In this study, we present a phylogenetic analysis of the genus Bruggmanniella Tavares based on morphological features. Cladistic analyses were conducted using 57 characters from 26 species. All species of Bruggmanniella except for B. byrsonimae were selected as ingroup and the genera Asphondylia Loew, Bruggmannia Tavares, Illiciomyia Tokuda, Parazalepidota Maia, Pseudasphondylia Monzen, Schizomyia Kieffer, and Lopesia Rübsaamen as outgroup. We used characters from larvae, pupae, adults, and galls. The results of this study supported Bruggmanniella as the sister group of Pseudasphondylia. Bruggmanniella actinodaphnes Tokuda and Yukawa and B. cinnamomi Tokuda and Yukawa have been moved to genus Pseudasphondylia (Pseudasphondylia actinodaphnes (Tokuda and Yukawa) comb. nov. and Pseudasphondylia cinnamomi (Tokuda and Yukawa) comb. nov.). The new genus Odontokeros gen. nov. has been erected for the single species Odontokeros brevipes (Lin, Yang & Tokuda) comb. nov. In addition, we described a new Brazilian species, Bruggmanniella miconia Garcia, Lamas and Urso-Guimarães sp. nov. Identification keys to the New World species of Bruggmanniella are presented.


Assuntos
Dípteros/classificação , Dípteros/fisiologia , Interações Hospedeiro-Parasita , Filogenia , Tumores de Planta/parasitologia , Animais , Brasil , Dípteros/anatomia & histologia , Feminino , Geografia , Larva/anatomia & histologia , Larva/fisiologia , Masculino , Pupa/anatomia & histologia , Pupa/fisiologia , Especificidade da Espécie
20.
Nat Protoc ; 15(3): 1158-1187, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32042177

RESUMO

The Drosophila larva has been used to investigate many processes in cell biology, including morphogenesis, physiology and responses to drugs and new therapeutic compounds. Despite its enormous potential as a model system, longer-term live imaging has been technically challenging because of a lack of efficient methods for immobilizing larvae for extended periods. We describe here a simple procedure for anesthetization and uninterrupted long-term in vivo imaging of the epidermis and other larval organs, including gut, imaginal discs, neurons, fat body, tracheae, muscles and hemocytes, for up to 8 h. We also include a procedure for probing cell properties by laser ablation. We provide a survey of the effects of different anesthetics, demonstrating that short exposure to diethyl ether is the most effective for long-term immobilization of larvae. This protocol does not require specific expertise beyond basic Drosophila genetics and husbandry, and confocal microscopy. It enables high-resolution studies of many systemic and subcellular processes in larvae.


Assuntos
Drosophila/anatomia & histologia , Microscopia Confocal/métodos , Gravação em Vídeo/métodos , Animais , Éter , Imobilização , Larva/anatomia & histologia , Fatores de Tempo
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