Dytiscidae Research Articles

Carnivorous Diving Beetles of the GenusDesmopachria(Coleoptera: Dytiscidae) from Brazil: New Species, New Records, and a Checklist

Carnivorous Diving Beetles of the Genus<i>Desmopachria</i>(Coleoptera: Dytiscidae) from Brazil: New Species, New Records, and a Checklist

Multitasking in an eye: the unusual organization of the Thermonectus marmoratus principal larval eyes allows for far and near vision and might aid in depth perception.

Very few visual systems diverge fundamentally from the basic plans of well-studied animal eyes. However, investigating those that do can provide novel insights into visual system function. A particularly unusual system exists in the principal larval eyes of a visually guided aquatic predator, the sunburst diving beetle, Thermonectus marmoratus (Coleoptera: Dystiscidae). These eyes are characterized by complex layered distal and proximal retinas. We previously reported that their principal eye E2 has a bifocal lens, and previous behavioral experiments suggested that these larvae have a unilateral range-finding mechanism that may involve their bizarre eye organization. In the present study, we expanded our optical measurements and found that: (1) E1 also has a bifocal lens, (2) E1 is best suited for far vision while E2 is best suited for near vision and (3) throughout their typical hunting range, the positions of focused images shift across specific retinal layers. This anatomical and optical organization in principle could support unilateral range finding. Taken together, our findings outline an unusual visual mechanism that is likely to be essential for the extraordinary hunting ability of these larvae.

Aquatic Coleoptera distribution patterns and their environmental drivers in central Portugal, Iberian Peninsula

Abstract Here, we present the distribution patterns of aquatic Coleoptera species collected in Central Portugal (240 samples, 136 stream sites) and their most important environmental drivers. A total of 81 species were identified from which 16 were endemic of the Iberian Peninsula confirming the high species richness and importance for conservation of this area. The families with higher species richness were Dytiscidae (24 species), Hydraenidae (16 species), Elmidae (13 species) and Hydrophilidae (12 species). We found six groups mainly based on altitudinal, conductivity and lithology gradients. We found a replacement of families, filling different niches over the catchments environmental gradients. According to the distribution maps, the families Dytiscidae and Hydrophilidae appeared in lowland streams while Hydraenidae were collected in upper stretches of the rivers. Various species appeared widely distributed along the different watersheds, most of them belonging to the families Elmidae and Hydraenidae. The highest species richness was found for the Hydraena , represented by 13 species in our study area. Some Hydraena species tend to co-occur at the same sites and have a high similarity in their distribution. This first study of ecological patterns of Coleopteran species in Portugal brought thus new insights to knowledge of this invertebrate group.

Copelatus cessaima sp. nov. (Coleoptera: Dytiscidae: Copelatinae): first record of a troglomorphic diving beetle from Brazil.

Copelatus cessaima sp. nov. is described from Brazil. The new species was collected in water puddles inside of caves found in an ironstone formation and has typical troglomorphic characters: the eyes and metathoracic wings are absent, the elytra are fused and the body has long setae. This is the second species of Copelatinae reported as troglomorphic and the first record of a troglomorphic Dytiscidae species in Brazil. The modified morphology of the new species and the lack of elytral striae make the placement of C. cessaima sp. nov. in one of the 15 recognized Copelatus species groups difficult. Thus, we assign the new species to a "group unknown" as defined in Nilsson's world catalogue of the family Dytiscidae.

CYTOCHEMICAL AND ULTRASTRUCTURAL STUDIES OF OOGENESIS IN THE DYTISCIDAE

SUMMARY Oogenesis of Dytiscidae is characterized by a remarkable phenomenon occurring in the germarium: each oogonium, after a series of normal mitoses, is transformed into a preoocyte characterized by a mass of extra- chromosomal chromatin called the Giardina mass or body or ring (GB), from the name of its Discoverer. The preoocyte undergoes four differential mitoses and the GB stays in only one cell, the oocyte, the other fifteen becoming nurse cells. The behaviour of this extrachromosomal formation is interesting but its significance is not completely clear, partly because it disintegrates and disappears during growth of the oocyte. Cytochemical study has shown that at its appearance the GB consists predominantly of DNA and at the time of its destruction there is an increasing synthesis of RNA. The results were obtained with a variety of cytochemical and autoradiographic techniques and have been confirmed by various Authors. The nurse cells grow too and their nuclei undergo numerous endomitoses. DNA sy...

Repeated Parallel Evolution Reveals Limiting Similarity in Subterranean Diving Beetles

The theory of limiting similarity predicts that co-occurring species must be sufficiently different to coexist. Although this idea is a staple of community ecology, convincing empirical evidence has been scarce. Here we examine 34 subterranean beetle communities in arid inland Australia that share the same habitat type but have evolved in complete isolation over the past 5 million years. Although these communities come from a range of phylogenetic origins, we find that they have almost invariably evolved to share a similar size structure. The relative positions of coexisting species on the body size axis were significantly more regular across communities than would be expected by chance, with a size ratio, on average, of 1.6 between coexisting species. By contrast, species' absolute body sizes varied substantially from one community to the next. This suggests that self-organized spacing according to limiting-similarity theory, as opposed to evolution toward preexisting fixed niches, shaped the communities. Using a model starting from random sets of founder species, we demonstrate that the patterns are indeed consistent with evolutionary self-organization. For less isolated habitats, the same model predicts the coexistence of multiple species in each regularly spaced functional group. Limiting similarity, therefore, may also be compatible with the coexistence of many redundant species.

Australasian sky islands act as a diversity pump facilitating peripheral speciation and complex reversal from narrow endemic to widespread ecological supertramp.

The Australasian archipelago is biologically extremely diverse as a result of a highly puzzling geological and biological evolution. Unveiling the underlying mechanisms has never been more attainable as molecular phylogenetic and geological methods improve, and has become a research priority considering increasing human-mediated loss of biodiversity. However, studies of finer scaled evolutionary patterns remain rare particularly for megadiverse Melanesian biota. While oceanic islands have received some attention in the region, likewise insular mountain blocks that serve as species pumps remain understudied, even though Australasia, for example, features some of the most spectacular tropical alpine habitats in the World. Here, we sequenced almost 2 kb of mitochondrial DNA from the widespread diving beetle Rhantus suturalis from across Australasia and the Indomalayan Archipelago, including remote New Guinean highlands. Based on expert taxonomy with a multigene phylogenetic backbone study, and combining molecular phylogenetics, phylogeography, divergence time estimation, and historical demography, we recover comparably low geographic signal, but complex phylogenetic relationships and population structure within R. suturalis. Four narrowly endemic New Guinea highland species are subordinated and two populations (New Guinea, New Zealand) seem to constitute cases of ongoing speciation. We reveal repeated colonization of remote mountain chains where haplotypes out of a core clade of very widespread haplotypes syntopically might occur with well-isolated ones. These results are corroborated by a Pleistocene origin approximately 2.4 Ma ago, followed by a sudden demographic expansion 600,000 years ago that may have been initiated through climatic adaptations. This study is a snapshot of the early stages of lineage diversification by peripatric speciation in Australasia, and supports New Guinea sky islands as cradles of evolution, in line with geological evidence suggesting very recent origin of high altitudes in the region.

Faunal diversity of aquatic insects in Surha Tal of District - Ballia (U. P.), India

Diversity of aquatic insect fauna of Surha Tal, district Ballia (U.P.) was studied during 2006-08. Twenty nine species of aquatic insect were collected. In class insect four orders namely Coleoptera, Hemiptera, Odonata and Diptera belonging to fourteen families Dytiscidae, Gyrinidae, Hydrophlidae Notonectidae, Palaeidae, Nepidae, Belostomatidae, Hydrometridae, Gerridae. Gomphidae, Libellulidae, Coegrionidae. Chironomidae, Culicidae having twenty genera and twenty nine species were identified.

Dytiscidae, Noteridae, Haliplidae, Hydraenidae, Hydrophilidae, Hydrochidae, Helophoridae, Spercheidae and Dryopidae (Coleoptera) of the Russian part of the Curonian Spit: an attempt of complex faunal analysis

An annotated checklist of nine сoleopteran families from the Russian part of the Curonian Spit has been compiled. The total amount of taxa include 90 species of 40 genera. The family Dytiscidae is represented by 42 species, Hydrophilidae by 32 species, Hydraenidae by five species, Helophoridae by three species, Haliplidae, Noteridae and Dryopidae by two species each, and Spercheidae and Hydrochidae by one species each. The specialised rheobiont and rheophil groups have not been recorded in the coleopterofauna of the Curonian Spit. On the contrary, the unspecialized eurybiont and stagnophil species associated with small temporal water bodies dominate. Especially interesting are the findings of species Hydroporus obscurus, Hygrotus parallelogrammus, Ilybius guttiger, Graphoderus austriacus, Peltodytes caesus, Cercyon castaneipennis, C. nigriceps, C. granarius, C. laminatus and Limnebius aluta. The possibility of habitation of aquatic Coleoptera in the Curonian Lagoon is discussed. Sudarytas devynių Coleopte...

Habitat type mediates equilibrium with climatic conditions in the distribution of Iberian diving beetles

ABSTRACTAim The contrasting habitat permanence over geological time‐scales of lotic and lentic habitats may impose different constraints on the dispersal ability of their macroinvertebrate populations, and ultimately on the degree of equilibrium with current climate. We aim to test for differences between species typical of either habitat type in their potential versus realized distributions as a surrogate measure of degree of climate equilibrium, both in refuges and more recently deglaciated areas.Location Western Europe.Methods We focus on 99 Iberian diving beetles (family Dytiscidae). A multidimensional envelope procedure was used to estimate their potential distributions, which were projected for different spatial scales. At the continental scale we calculated the percentage of countries with climatically suitable conditions for each species over those actually occupied (range filling). At the regional scale, we estimated realized distributions using: (1) convex hull polygons for Sweden and the Iberian Peninsula; and (2) generalized linear models for the Iberian Peninsula.Results In the Iberian Peninsula, differences in the degree of equilibrium with climatic conditions between lotic and lentic species were few, if any. However, at the continental scale we found significant differences, with lentic species closer to equilibrium than lotic species. In the recently deglaciated area (Sweden) the subset of species with ranges wide enough to encompass Iberia and Scandinavia were mostly lentic, and all were closer to climatic equilibrium without significant differences between habitat types.Main conclusions Our results show that, at continental scales, climate equilibrium is not concordant between the habitat types across western Europe. We hypothesize that: (1) the differences between refuge areas in dispersal ability are erased probably due to long‐term climatic stability, allowing enough time to reach equilibrium, and (2) the species with wide geographical ranges able to recolonize recently deglaciated areas should have the highest dispersal abilities, and are closer to climatic equilibrium.

Ectopic opsin expression in Drosophila: Investigating the spectral sensitivity of Sunburst Diving Beetle larval photoreceptors.

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What do Sunburst Diving beetle larvae see? The role of polarization sensitivity

Event Abstract Back to Event What do Sunburst Diving beetle larvae see? The role of polarization sensitivity Annette Stowasser1* and Elke K. Buschbeck1 1 University of Cincinnati, Department of Biological Sciences, United States Although polarization sensitivity has been studied fairly well in adult insects, little is known about it in larvae. Nevertheless it is likely that at least some larvae, such as Thermonectus marmoratus, could substantially benefit from it. In previous work, the possibility of polarization sensitivity in one of their retinas had been raised based on the ultrastructure. However, because light travels through more distal photoreceptors (that potentially could influence polarization) before reaching this region, the polarization sensitivity remained unclear. We used electrophysiological methods and single-cell staining to confirm polarization sensitivity in the proximal retina of eyes E1 and E2. Larvae of the aquatic beetle T. marmoratus are highly successful visually guided predators. Their principal eyes E1 and E2 each have a single lens, are tubular in shape, and have at least two distinct retinas: the distal and proximal retinas. The former is sensitive to green light, whereas, the latter is sensitive to UV light. Based on transmission electron microscopy the proximal retina of E1 and E2 is composed of three distinct cell types: T1, T2, and T3. These cells are arranged in an alternating pattern. Cells of type T1 and T2 are somewhat larger, and have vertically and horizontally aligned microvilli, respectively. T3 is organized similar to T1, but it’s rhabdomeric portion is much smaller. As expected from the ultrastructure, cells of the type T1 are most sensitive to vertically polarized light, while cells of the type T2 are most sensitive to horizontally polarized light. While we could not directly confirm the polarization sensitivity of T3 cells, there is evidence that we recorded from all three morphologically distinct cell types. Two cell populations were most sensitive to vertically polarized light, with polarization sensitivity (PS) values of 13.9 (± 7.5 s.d., n = 16) and 3.1 (± 0.4 s.d., n = 4) respectively. Cells most sensitive to horizontally polarized light showed a PS value of 9.3 (± 3.2 s.d., n = 14). Compared to other insects these values are relatively high, suggesting that polarization sensitivity likely plays an important role in the visual system of these larvae. Based on their natural history and behavior, possible functions are: (1) finding water after hatching, (2) finding the shore before pupation, and (3) making prey more visible, by filtering out horizontally polarized haze, and/or by using polarization features for prey detection. Behavioral experiments will be necessary to determine for which of these behaviors polarization sensitivity might be important. Acknowledgements We thank John E. Layne for lending us his rotating arm. We thank Shannon Werner for helping with beetle care and Randy Morgan and the Cincinnati Zoo & Botanical Garden for providing Sunburst Diving Beetles. This work was supported by the NSF (IOS0545978 and IOS1050754). Keywords: coleoptera, Dytiscidae, stemmata Conference: Tenth International Congress of Neuroethology, College Park. Maryland USA, United States, 5 Aug - 10 Aug, 2012. Presentation Type: Poster Presentation (see alternatives below as well) Topic: Sensory: Vision Citation: Stowasser A and Buschbeck EK (2012). What do Sunburst Diving beetle larvae see? The role of polarization sensitivity . Conference Abstract: Tenth International Congress of Neuroethology. doi: 10.3389/conf.fnbeh.2012.27.00172 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 27 Apr 2012; Published Online: 07 Jul 2012. * Correspondence: Ms. Annette Stowasser, University of Cincinnati, Department of Biological Sciences, Cincinnati, United States, annette.stowasser@uc.edu Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Annette Stowasser Elke K Buschbeck Google Annette Stowasser Elke K Buschbeck Google Scholar Annette Stowasser Elke K Buschbeck PubMed Annette Stowasser Elke K Buschbeck Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Diversidad de los Macroinvertebrados Acuáticos de la Laguna de Sonso, Valle del Cauca, Colombia

Se evaluó la diversidad de macroinvertebrados acuáticos bentónicos y asociados a macrófitas En la laguna de Sonso entre 2007 y 2008. Se tomaron muestras en diferentes estaciones con una pala draga de 500 mi de capacidad y con redes de 4 m2 y 0.5 pm de ojo de malla respectivamente. Se realizó un análisis cualitativo de la variación temporal de los macroinvertebrados acuáticos de la laguna de Sonso y descripción de algunos aspectos sobre la ecología de estos organismos usando la literatura científica e institucional disponible. Entre 1998 y 2006 se reportaron aproximadamente 45 Familias pertenecientes a diferentes gremios tróficos y características de calidades de agua que van desde muy contaminadas (Tubificidae y Chironomidae) hasta muy limpias y propias de cuerpos de agua lóticos (Blephariceridae y Psephenidae). En los muéstreos realizados entre 2007 y 2008 se reportan principalmente organismos característicos de aguas con cierto nivel de materia orgánica (Hydrophilidae, Curculionidae, Chironomidae, Oligochaeta e Hirudinea). También se recolectaron moluscos gasterópodos y bivalvos. La familia Dytiscidae se colecto principalmente asociada al buchón de agua Eichornia crassipes. Los resultados presentados son un aporte para el conocimiento de la biodiversidad de los ecosistemas lénticos y constituye información básica para el establecimiento de políticas de normatividad e implementación de planes de manejo en la laguna.

Diving beetles (Coleoptera: Dytiscidae) from the Transylvanian society collection of the Natural History Museum of Sibiu (Romania)

Diving beetles (Coleoptera: Dytiscidae) from the Transylvanian society collection of the Natural History Museum of Sibiu (Romania) The present study, which deals with the Dytiscidae specimens preserved in the Transylvanian Society Collection of the Natural History Museum of Sibiu, represents a faunistic list of the genera and species present in this collection. The 851 specimens identified from the family Dytiscidae are Palaearctic species, belong to 125 species following the classification system proposed by Nilsson in 2010: 6 subfamilies, 14 tribes, 30 genera and 10 subgenera. This study is also a recall for researchers regarding the museum entomological collection, which was realized through the great effort of the Transylvanian Society members.

Some Organisms' Life Conservation in the Wild Barren Ponds

There are many organisms are adapt in their environments. There are usually hosts for being other organisms a live in their environments. The life is take many shapes and has special characters for more than one organism. From these environments are the freshwater and wild ponds in the wild. This study is proof that the life could be preserved in the wild ponds soil by exploring insects eggs in the soil with mentioned that it is completely dry. In the wild land in Oman country in Sumail, there were observations fieldtrips done and five samples from dry soil in the wild ponds. In separated places the samples are taken from five ponds soil. In five bowls which put in a water that are observed in one week. The observations of the separated soil pond in the wild are being in inconsecutive days. In the first and third days the soils are put in the bowls which containing the water and remarking the strains are dropped in the bottom of the bowls. In the fifth and the seventh days the soil sediments are constructed in the bottom and the insects eggs are float in or toward water surface. From the organisms that are being preserved are (Predacious Diving Beetles, Crawling water beetles), tadpoles (Bufo arabicus) and eggs of toads (Bufo arabicus) as well as larvae of mosquitoes and their eggs.

Parallel habitat‐driven differences in the phylogeographical structure of two independent lineages of Mediterranean saline water beetles

It has been hypothesized that species living in small lentic water bodies, because of the short-term geological persistence of their habitat, should show higher dispersal ability, with increased gene flow among populations and a less pronounced phylogeographical structure. Conversely, lotic species, living in more geologically stable habitats, should show reduced dispersal and an increased phylogeographical structure at the same geographical scales. In this work we tested the influence of habitat type in two groups of aquatic Coleoptera (Nebrioporus ceresyi and Ochthebius notabilis groups, families Dytiscidae and Hydraenidae respectively), each of them with closely related species typical of lotic and lentic saline Western Mediterranean water bodies. We used mitochondrial cox1 sequence data of 453 specimens of 77 populations through the range of nine species to compare a lotic vs. a lentic lineage in each of the two groups. Despite the differences in biology (predators vs. detritivorous) and evolutionary history, in both lotic lineages there was a higher proportion of nucleotide diversity among than within groups of populations, and a faster rate of accumulation of haplotype diversity (as measured by rarefaction curves) than in the lentic lineages. Similarly, lotic lineages had a higher absolute phylogenetic diversity, more remarkable considering their smaller absolute geographical ranges. By comparing closely related species, we were able to show the effect of contrasting habitat preferences in two different groups, in agreement with predictions derived from habitat stability.

Checklist of Gyrinidae, Haliplidae, Noteridae and Dytiscidae of Turkey (Coleoptera: Adephaga)

An updated species list of four beetle families is given for Turkey. A total of 35 genera and 167 species and subspecies are known to occur in Turkey. Ten species and two subspecies are from the family Gyrinidae, 16 species are from the family Haliplidae, three species are from the family Noteridae and 129 species and seven subspecies are from the family Dytiscidae.

Edible aquatic Coleoptera of the world with an emphasis on Mexico

Anthropoentomophagy is an ancient culinary practice wherein terrestrial and aquatic insects are eaten by humans. Of these species of insects, terrestrial insects are far more commonly used in anthropoentomophagy than aquatic insects. In this study we found that there are 22 genera and 78 species of edible aquatic beetles in the world. The family Dytiscidae hosts nine genera, Gyrinidae one, Elmidae two, Histeridae one, Hydrophilidae six, Haliplidae two and Noteridae one. Of the recorded species, 45 correspond to the family Dytiscidae, 19 to Hydrophilidae, three to Gyrinidae, four to Elmidae, two to Histeridae, four to Haliplidae and one to Noteridae. These beetles are the most prized organisms of lentic watersThe family that has the highest number of edible food insect genera and species is Dytiscidae. Here, the global geographic distribution of species in these organisms is shown, and a discussion is presented of its importance as a renewable natural resource widely used for food in various countries.

Aquatic beetle species and their distributions in Xinjiang, China

The species of aquatic beetles and their distributions in lotic and lentic habitats were investigated during July to August of 2005 and 2006 in Xinjiang Uygur Autonomous Region, China. A total of 66 species belonging to 7 beetle families (Dytiscidae, Gyrinidae, Haliplidae, Helophoridae, Noteridae, Hydraenidae, Hydrophilidae) are recorded, of which 16 are new records of aquatic beetles for China.

Aquatic and Semiaquatic Beetles of the Great Smoky Mountains National Park (Coleoptera: Dytiscidae, Gyrinidae, Haliplidae, Helophoridae, Hydraenidae, Hydrochidae, Hydrophilidae, and Noteridae)

Aquatic and semiaquatic beetles in the families Dytiscidae, Gyrinidae, Haliplidae, Helophoridae, Hydraenidae, Hydrophilidae, and Noteridae of the Great Smoky Mountains National Park (GSMNP) were sampled from 2003 to 2006. Current and historic literature as well as the insect collections at GSMNP, Illinois Natural History Survey, Smithsonian Institution, and University of Tennessee were examined for GSMNP records. This is the first comprehensive effort at surveying the aquatic and semiaquatic beetles of GSMNP. A total of 115 species were recorded: 46 Dytiscidae, 7 Gyrinidae, 5 Haliplidae, 2 Helophoridae, 2 Hydraenidae, 2 Hydrochidae, 49 Hydrophilidae, and 2 Noteridae. Eighty species are reported from GSMNP for the first time. Hydaticus aruspex Clark, Hydrocolus deflatus, H. paugus, Liodessus affinis (Dytiscidae), and Dactylosternum abdominale (Hydrophilidae) are reported from Tennessee for the first time.