Invertebrate Zoology

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News Article | May 2, 2017
Site: phys.org

A single spotted salamander embryo encased in an egg, which is green due to the presence of symbiotic algae. Credit: © Roger Hangarter New research shows how two drastically different organisms—a green alga and the spotted salamander—get along as cellular roommates. Scientists at the American Museum of Natural History and Gettysburg College found that this symbiosis, the only known example that includes a vertebrate species, puts stress on algal cells, changing the way they make energy, but does not seem to negatively impact salamander cells. The work is published today in the journal eLife. "Science shows us the many ways that life is interconnected, especially on the microscopic level, where we see how many organisms depend on close contact with or internalization of other species for food, defense, or reproduction," said lead author John Burns, a postdoctoral researcher in the Museum's Division of Invertebrate Zoology. "But the relationship between this particular alga and salamander is very unusual." Scientists have known for more than a century that a green alga (Oophila amblystomatis) grows in the egg cases of the spotted salamander (Ambystoma maculatum)—the strange pairing is visible to the naked eye in the green hue of salamanders' eggs. The symbiosis was originally thought to occur only between the salamander embryo and the algae living outside it. The embryos produce nitrogen-rich waste that is useful to algae, and the algae increases the oxygen content of the fluid around the respiring embryos. But recent research has revealed that the algae are actually located inside cells all over the spotted salamander's body. This cell-within-a-cell relationship can also be found in corals and in the guts of cicadas, but the green alga-spotted salamander interaction is the only known example of a symbiont entering the cells of a vertebrate species. "This is really such a strange arrangement to think about, that the salamanders allow the algae to live in their egg cases. It would be like having a bunch of green algae in a womb," said study co-author Ryan Kerney, an assistant professor at Gettysburg College. "What we set out to look at now is the kind of molecular change that happens when the salamander cells and green algae cells are together." In the new eLife study, the researchers compared RNA from the cells of five different groups: salamander cells with algae, salamander cells without algae, the algal cells living in salamander cells, the algae living in the egg capsules, and algae cultured in the laboratory. They found that algae inside salamander cells are stressed and change the way they make energy. Instead of using light energy to produce food to support the salamander host, as happens in coral-algae interactions, the algae in salamander cells struggle to adapt to their new environment. Whether the algae benefits from this cell-within-a-cell interaction remains unclear. In stark contrast, affected salamander cells appear to recognize the alga as foreign but show no signs of stress during the interaction. The researchers found that the salamanders overexpress several genes that might suppress an immune response, suggesting that the host cell experience is neutral or beneficial. "We are learning that these two fundamentally different cells are changing each other dramatically, and this might be relevant for other symbiotic systems, including human and parasitic microbe relationships," said study co-author Eunsoo Kim, an assistant curator in the Museum's Division of Invertebrate Zoology. More information: John A Burns et al, Transcriptome analysis illuminates the nature of the intracellular interaction in a vertebrate-algal symbiosis, eLife (2017). DOI: 10.7554/eLife.22054


News Article | May 2, 2017
Site: www.eurekalert.org

New research shows how two drastically different organisms--a green alga and the spotted salamander--get along as cellular roommates. Scientists at the American Museum of Natural History and Gettysburg College found that this symbiosis, the only known example that includes a vertebrate species, puts stress on algal cells, changing the way they make energy, but does not seem to negatively impact salamander cells. The work is published today in the journal eLife. "Science shows us the many ways that life is interconnected, especially on the microscopic level, where we see how many organisms depend on close contact with or internalization of other species for food, defense, or reproduction," said lead author John Burns, a postdoctoral researcher in the Museum's Division of Invertebrate Zoology. "But the relationship between this particular alga and salamander is very unusual." Scientists have known for more than a century that a green alga (Oophila amblystomatis) grows in the egg cases of the spotted salamander (Ambystoma maculatum)--the strange pairing is visible to the naked eye in the green hue of salamanders' eggs. The symbiosis was originally thought to occur only between the salamander embryo and the algae living outside it. The embryos produce nitrogen-rich waste that is useful to algae, and the algae increases the oxygen content of the fluid around the respiring embryos. But recent research has revealed that the algae are actually located inside cells all over the spotted salamander's body. This cell-within-a-cell relationship can also be found in corals and in the guts of cicadas, but the green alga-spotted salamander interaction is the only known example of a symbiont entering the cells of a vertebrate species. "This is really such a strange arrangement to think about, that the salamanders allow the algae to live in their egg cases. It would be like having a bunch of green algae in a womb," said study co-author Ryan Kerney, an assistant professor at Gettysburg College. "What we set out to look at now is the kind of molecular change that happens when the salamander cells and green algae cells are together." In the new eLife study, the researchers compared RNA from the cells of five different groups: salamander cells with algae, salamander cells without algae, the algal cells living in salamander cells, the algae living in the egg capsules, and algae cultured in the laboratory. They found that algae inside salamander cells are stressed and change the way they make energy. Instead of using light energy to produce food to support the salamander host, as happens in coral-algae interactions, the algae in salamander cells struggle to adapt to their new environment. Whether the algae benefits from this cell-within-a-cell interaction remains unclear. In stark contrast, affected salamander cells appear to recognize the alga as foreign but show no signs of stress during the interaction. The researchers found that the salamanders overexpress several genes that might suppress an immune response, suggesting that the host cell experience is neutral or beneficial. "We are learning that these two fundamentally different cells are changing each other dramatically, and this might be relevant for other symbiotic systems, including human and parasitic microbe relationships," said study co-author Eunsoo Kim, an assistant curator in the Museum's Division of Invertebrate Zoology. Other authors on this study include Huanjia Zhang and Elizabeth Hill, undergraduate students at Gettysburg College. This work was supported, in part, by the Howard Hughes Medical Institute and the National Science Foundation, grant #s 1428065 and #1453639. For more information about this project, see this recent episode of the Museum's Shelf Life series: http://www. The American Museum of Natural History, founded in 1869, is one of the world's preeminent scientific, educational, and cultural institutions. The Museum encompasses 45 permanent exhibition halls, including the Rose Center for Earth and Space and the Hayden Planetarium, as well as galleries for temporary exhibitions. It is home to the Theodore Roosevelt Memorial, New York State's official memorial to its 33rd governor and the nation's 26th president, and a tribute to Roosevelt's enduring legacy of conservation. The Museum's five active research divisions and three cross-disciplinary centers support approximately 200 scientists, whose work draws on a world-class permanent collection of more than 34 million specimens and artifacts, as well as specialized collections for frozen tissue and genomic and astrophysical data, and one of the largest natural history libraries in the world. Through its Richard Gilder Graduate School, it is the only American museum authorized to grant the Ph.D. degree and the Master of Arts in Teaching degree. Annual attendance has grown to approximately 5 million, and the Museum's exhibitions and Space Shows can be seen in venues on five continents. The Museum's website and collection of apps for mobile devices extend its collections, exhibitions, and educational programs to millions more beyond its walls. Visit amnh.org for more information.


Cobb T.P.,Invertebrate zoology | Morissette J.L.,University of Alberta | Jacobs J.M.,University of Alberta | Koivula M.J.,University of Alberta | And 2 more authors.
Conservation Biology | Year: 2011

In Canada and the United States pressure to recoup financial costs of wildfire by harvesting burned timber is increasing, despite insufficient understanding of the ecological consequences of postfire salvage logging. We compared the species richness and composition of deadwood-associated beetle assemblages among undisturbed, recently burned, logged, and salvage-logged, boreal, mixed-wood stands. Species richness was lowest in salvage-logged stands, largely due to a negative effect of harvesting on the occurrence of wood- and bark-boring species. In comparison with undisturbed stands, the combination of wildfire and logging in salvage-logged stands had a greater effect on species composition than either disturbance alone. Strong differences in species composition among stand treatments were linked to differences in quantity and quality (e.g., decay stage) of coarse woody debris. We found that the effects of wildfire and logging on deadwood-associated beetles were synergistic, such that the effects of postfire salvage logging could not be predicted reliably on the basis of data on either disturbance alone. Thus, increases in salvage logging of burned forests may have serious negative consequences for deadwood-associated beetles and their ecological functions in early postfire successional forests. © 2010 Society for Conservation Biology.


Reyes-Rosas M.A.,Instituto Nacional Investigaciones Forestales Agricolas y Pecuarias INIFAP | Lopez-Arroyo J.I.,INIFAP CIRNE | Buck M.,Invertebrate Zoology | Loera-Gallardo J.,Instituto Nacional Investigaciones Forestales Agricolas y Pecuarias INIFAP
Florida Entomologist | Year: 2011

Since 2008, in México, a new natural enemy of Diaphorinacitri has been observed predating on nymphs of this psyllid vector of citrus greening disease. This wasp was identified as Brachygastra mellifica (Say 1837), the Mexican honey wasp. This wasp was observed attacking all D. citri nymph instars, and it appears to have the potential to serve as a tool in integrated biological control programs.


Marshall S.A.,University of Guelph | Rohacek J.,Silesian Museum | Dong H.,Shenzhen Fairylake Botanical Garden | Buck M.,Invertebrate Zoology
Acta Entomologica Musei Nationalis Pragae | Year: 2011

The taxonomy and nomenclature of the family Sphaeroceridae (Diptera: Acalyptratae) is reviewed in the context of a world catalog and bibliography covering the last decade (2000-2010). Bispinicerca Su & Liu, 2009, syn. nov., is synonymized with Opacifrons Duda, 1918 and the following new combinations are given: Opacifrons liupanensis (Su & Liu, 2009), comb. nov., Pseudopterogramma annectens (Richards, 1964), comb. nov., Pseudopterogramma brevivenosum (Tenorio, 1967), comb. nov., and Pseudopterogramma conicum (Richards, 1946), comb. nov. Thirty genera and 211 species were added to the family between 2000 and 2010, giving a current total of 141 genera and 1,550 species. A gallery with 32 macrophotographs is provided, depicting 32 species of 30 genera representing 3 subfamilies of Sphaeroceridae. A world bibliography of Sphaeroceridae is supplemented with 306 references.


Walter D.E.,Invertebrate Zoology | Proctor H.C.,University of Alberta
Acarologia | Year: 2010

We present a literature survey and analysis of the profile of mites (Acari, exclusive of Ixodida) in recent literature and on the World Wide Web, and compare their prominence to that of spiders (Araneae). Despite having approximately the same number of described species, spiders outshine mites on the Web, although the study of mites (Acarology) is better represented than the study of spiders (Araneology). Broad searches of scientific literature imply that publications on mites exceed those on spiders by 2-3x; however, this dominance was reversed when a smaller number of journals with broad readerships and no taxonomic orientation (e.g., Nature, Science) were surveyed. This latter analysis revealed that the topical content of mite and spider papers in these general-science journals differs significantly. A troubling leveling-off of taxonomic publications on mites also was discovered. We conclude by suggesting some strategies that acarologists and editorial boards might follow in order to raise mites to their proper status as exemplary models for ecological and evolutionary research. © 2009-2011 ACAROLOGIA.


Behan-Pelletier V.M.,Agriculture and Agri Food Canada | Walter D.E.,Invertebrate Zoology
Zootaxa | Year: 2013

Species in the oribatid mite genus Tectoribates are primarily Palaearctic and Neotropical, with scattered, unidentified records from North America. Herein, we describe 3 new Tectoribates species from dry forest and prairie habitats in North America: T. alcecampestris sp. nov., from Alberta, T. borealis sp. nov., from southern Alberta and Ontario, both on the basis of adults and nymphs, and T. campestris sp. nov., from dry grassland habitats in Ontario and Kansas, on the basis of adults. We provide a revised and expanded diagnosis for adults of Tectoribates. We assess relationships of Tectoribates, using characters of adults and newly discovered apheredermous, plicate immatures. We include observations on Pseudotectoribates which is closely related to Tectoribates. The closest relatives of these genera are hypothesised to be among the Tegoribatidae (Achipterioidea) rather than among the Achipteriidae (Achipterioidea), Oribatellidae (Oribatelloidea), or Ceratozetoidea, as suggested in previous classifications. Finally, we give a key to adults of the world fauna of Tectoribates. © 2013 Magnolia Press.


Behan-Pelletier V.M.,Agriculture and Agri Food Canada | Walter D.E.,Invertebrate Zoology
Zootaxa | Year: 2012

The oribatid mite genus Oribatella (Oribatellidae) includes 18 species known previously from North America. Herein, we describe 11 new Oribatella species from montane, subarctic, forest and prairie habitats in western North America: O. abmi sp. nov., O. banksi sp. nov., O. ewingi sp. nov., O. heatherae sp. nov., O. manningensis sp. nov., O. maryae sp. nov., O. oregonensis sp. nov., O. parallelus sp. nov., O. pawnee sp. nov., O. sintranslamella and O. yukonensis sp. nov. Descriptions of two species (O. heatherae and O. pawnee) include some developmental instars. That of O. yukonensis includes all instars; nymphs retain dorsocentral setae dm and dp, but the setal morphology changes between larva and nymphs. These immatures bear sclerotized areas on the hysterosoma. Adults of Oribatella oregonensis show distinct sexual dimorphism, with three notogastral setae arising from fused porose areas in the male. We provide new distribution records for Oribatella species previously known from North America, including O. arctica Thor, 1930, O. Canadensis Behan-Pelletier and Eamer, 2010, O. jacoti Behan-Pelletier, 2011 and O. reticulatoides Hammer, 1955, and remark on O. anomola Grabowski, 1970. We clarify description of the octotaxic system and the interlamellar region in species of Oribatella and discuss variability in hysterosomal sclerotization and setation in immatures. Finally, we give a key to adults of the 29 species of Oribatella now known from North America. © 2012 Magnolia Press All rights reserved.


Clark R.N.,Invertebrate Zoology | Jewett S.C.,University of Alaska Fairbanks
Zootaxa | Year: 2011

A new species of goniasterid sea star, Hippasteria aleutica sp. nov. is described from the Aleutian Islands, and compared to H. phrygiana (Parelius, 1768) from the North Atlantic-Arctic, as well as its congeners from the North Pacific. Distribution is discussed and a key to the described species of Hippasteria in Alaskan waters is presented. © 2011 - Magnolia Press.


Buck M.,Invertebrate Zoology | Cobb T.P.,Invertebrate Zoology | Stahlhut J.K.,University of Guelph | Hanner R.H.,University of Guelph
Zootaxa | Year: 2012

A study of male genitalia, morphometric head measurements and DNA barcoding revealed three overlooked species in eastern Nearctic Polistes (Fuscopolistes), two of which are described here: P. (F.) hirsuticornis Buck, sp. nov. and P. (F.) parametricus Buck, sp. nov. Polistes carolina of authors is a complex of two or three species. Type studies also uncovered new synonymies: P. rubiginosus Lepeletier, 1836, sp. restit. (=P. perplexus Cresson, 1872, syn. nov.; P. generosus Cres-son, 1872, syn. nov.); P. nigripennis (De Geer, 1773) is removed from synonymy with P. carolina (Linnaeus, 1767) and tentatively synonymized with P. canadensis (Linnaeus, 1758) (=Vespa nigripennis De Geer, 1773, syn. nov.). A revised key to eastern Nearctic Fuscopolistes Richards, 1973 is presented. The male genitalia of eastern Nearctic species are il-lustrated in detail for the first time, and a preliminary genitalic key is presented. DNA barcoding revealed strongly diver-gent genetic lineages in three species besides "P. carolina". A so-called 'barcoding gap' was not detected, thereby ruling out species delimitation through divergence thresholds. Indirect evidence suggests that the newly described species may be obligate social parasites. Copyright © 2012 · Magnolia Press.

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