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Piersanti S, Rebora M, Salerno G, Vitecek S, Anton S. Sensory pathway in aquatic basal polyneoptera: Antennal sensilla and brain morphology in stoneflies. Arthropod Struct Dev 2024; 79:101345. [PMID: 38493543 DOI: 10.1016/j.asd.2024.101345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2023] [Revised: 02/27/2024] [Accepted: 02/27/2024] [Indexed: 03/19/2024]
Abstract
Aquatic insects represent a great portion of Arthropod diversity and the major fauna in inland waters. The sensory biology and neuroanatomy of these insects are, however, poorly investigated. This research aims to describe the antennal sensilla of nymphs of the stonefly Dinocras cephalotes using scanning electron microscopy and comparing them with the adult sensilla. Besides, central antennal pathways in nymphs and adults are investigated by neuron mass-tracing with tetramethylrhodamine, and their brain structures are visualized with an anti-synapsin antibody. No dramatic changes occur in the antennal sensilla during nymphal development, while antennal sensilla profoundly change from nymphs to adults when switching from an aquatic to an aerial lifestyle. However, similar brain structures are used in nymphs and adults to process diverging sensory information, perceived through different sensilla in water and air. These data provide valuable insights into the evolution of aquatic heterometabolous insects, maintaining a functional sensory system throughout development, including a distinct adaptation of the peripheral olfactory systems during the transition from detection of water-soluble chemicals to volatile compounds in the air. From a conservation biology perspective, the present data contribute to a better knowledge of the biology of stoneflies, which are very important bioindicators in rivers.
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Affiliation(s)
- Silvana Piersanti
- Dipartimento di Chimica, Biologia e Biotecnologie, University of Perugia, Via Elce di Sotto 8, 06123, Perugia, Italy.
| | - Manuela Rebora
- Dipartimento di Chimica, Biologia e Biotecnologie, University of Perugia, Via Elce di Sotto 8, 06123, Perugia, Italy.
| | - Gianandrea Salerno
- Dipartimento di Scienze Agrarie, Alimentari e Ambientali, University of Perugia, Borgo XX Giugno 74, 06121, Perugia, Italy.
| | - Simon Vitecek
- QUIVER, WasserCluster Lunz -Biologische Station, Dr.-Carl-Kupelwieserpromenade5, 3293, Lunz am See, Austria; Institute of Hydrobiology and Aquatic Ecosystem Management, University of Natural Resources and Life Sciences, Gregor-Mendel-Straße 33, 1180, Vienna, Austria.
| | - Sylvia Anton
- IGEPP, INRAE, Institut Agro, University of Rennes, 2, rue André Le Nôtre, 49045, Angers Cedex 01, France.
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2
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Fabian J, Siwanowicz I, Uhrhan M, Maeda M, Bomphrey RJ, Lin HT. Systematic characterization of wing mechanosensors that monitor airflow and wing deformations. iScience 2022; 25:104150. [PMID: 35465360 PMCID: PMC9018384 DOI: 10.1016/j.isci.2022.104150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Revised: 02/07/2022] [Accepted: 03/21/2022] [Indexed: 11/30/2022] Open
Abstract
Animal wings deform during flight in ways that can enhance lift, facilitate flight control, and mitigate damage. Monitoring the structural and aerodynamic state of the wing is challenging because deformations are passive, and the flow fields are unsteady; it requires distributed mechanosensors that respond to local airflow and strain on the wing. Without a complete map of the sensor arrays, it is impossible to model control strategies underpinned by them. Here, we present the first systematic characterization of mechanosensors on the dragonfly’s wings: morphology, distribution, and wiring. By combining a cross-species survey of sensor distribution with quantitative neuroanatomy and a high-fidelity finite element analysis, we show that the mechanosensors are well placed to perceive features of the wing dynamics relevant to flight. This work describes the wing sensory apparatus in its entirety and advances our understanding of the sensorimotor loop that facilitates exquisite flight control in animals with highly deformable wings. Dragonfly wings are innervated by an extensive collection of sensory neurons Mechanosensors are spread across the whole span of the wing with consistent patterns The axons of wing sensory neurons are scaled to compensate for transmission latencies Anatomically accurate models reveal wing strain fields that inform sensor distribution
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Affiliation(s)
- Joseph Fabian
- Imperial College London, London, SW7 2AZ, UK.,The University of Adelaide, Adelaide, South Australia, 5005, Australia
| | | | | | | | | | - Huai-Ti Lin
- Imperial College London, London, SW7 2AZ, UK
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3
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Piersanti S, Salerno G, Di Pietro V, Giontella L, Rebora M, Jones A, Fincke OM. Tests of search image and learning in the wild: Insights from sexual conflict in damselflies. Ecol Evol 2021; 11:4399-4412. [PMID: 33976818 PMCID: PMC8093675 DOI: 10.1002/ece3.7335] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 01/26/2021] [Accepted: 01/27/2021] [Indexed: 02/05/2023] Open
Abstract
Search image formation, a proximal mechanism to maintain genetic polymorphisms by negative frequency-dependent selection, has rarely been tested under natural conditions. Females of many nonterritorial damselflies resemble either conspecific males or background vegetation. Mate-searching males are assumed to form search images of the majority female type, sexually harassing it at rates higher than expected from its frequency, thus selectively favoring the less common morph. We tested this and how morph coloration and behavior influenced male perception and intersexual encounters by following marked Ischnura elegans and noting their reactions to conspecifics. Contrary to search image formation and associative learning hypotheses, although males encountered the minority, male-like morph more often, sexual harassment and clutch size were similar for both morphs. Prior mating attempts or copula with morphs did not affect a male's subsequent reaction to them; males rarely attempted matings with immature females or males. Females mated early in the day, reducing the opportunity for males to learn their identity beforehand. Once encountered, the male-like morph was more readily noticed by males than the alternative morph, which once noticed was more likely to receive mating attempts. Flexible behavior gave morphs considerable control over their apparency to males, influencing intersexual encounters. Results suggested a more subtle proximal mechanism than male learning maintains these color polymorphisms and call for inferences of learning to be validated by behavior of wild receivers and their signalers.
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Affiliation(s)
- Silvana Piersanti
- Dipartimento di Chimica, Biologia, e BiotecnologieUniversity of PerugiaPerugiaItaly
| | - Gianandrea Salerno
- Dipartimento di Scienze Agrarie, Alimentari e AmbientaliUniversity of PerugiaPerugiaItaly
| | - Viviana Di Pietro
- Department of Life Science and SystemticsUniversity of TorinoTorinoItaly
| | - Leonardo Giontella
- Dipartimento di Chimica, Biologia, e BiotecnologieUniversity of PerugiaPerugiaItaly
| | - Manuela Rebora
- Dipartimento di Chimica, Biologia, e BiotecnologieUniversity of PerugiaPerugiaItaly
| | - Albyn Jones
- Department of MathematicsReed CollegePortlandORUSA
| | - Ola M. Fincke
- Department of BiologyUniversity of OklahomaNormanOKUSA
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Ezaki K, Yamashita T, Carle T, Watanabe H, Yokohari F, Yamawaki Y. Aldehyde-specific responses of olfactory sensory neurons in the praying mantis. Sci Rep 2021; 11:1856. [PMID: 33473161 DOI: 10.1038/s41598-021-81359-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Accepted: 12/31/2020] [Indexed: 11/09/2022] Open
Abstract
Although praying mantises rely mainly on vision for predatory behaviours, olfaction also plays a critical role in feeding and mating behaviours. However, the receptive processes underlying olfactory signals remain unclear. Here, we identified olfactory sensory neurons (OSNs) that are highly tuned to detect aldehydes in the mantis Tenodera aridifolia. In extracellular recordings from OSNs in basiconic sensilla on the antennae, we observed three different spike shapes, indicating that at least three OSNs are housed in a single basiconic sensillum. Unexpectedly, one of the three OSNs exhibited strong excitatory responses to a set of aldehydes. Based on the similarities of the response spectra to 15 different aldehydes, the aldehyde-specific OSNs were classified into three classes: B, S, and M. Class B broadly responded to most aldehydes used as stimulants; class S responded to short-chain aldehydes (C3–C7); and class M responded to middle-length chain aldehydes (C6–C9). Thus, aldehyde molecules can be finely discriminated based on the activity patterns of a population of OSNs. Because many insects emit aldehydes for pheromonal communication, mantises might use aldehydes as olfactory cues for locating prey habitat.
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Piersanti S, Rebora M, Salerno G, Anton S. The Antennal Pathway of Dragonfly Nymphs, from Sensilla to the Brain. Insects 2020; 11:E886. [PMID: 33339188 PMCID: PMC7765675 DOI: 10.3390/insects11120886] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 12/09/2020] [Accepted: 12/15/2020] [Indexed: 11/25/2022]
Abstract
Dragonflies are hemimetabolous insects, switching from an aquatic life style as nymphs to aerial life as adults, confronted to different environmental cues. How sensory structures on the antennae and the brain regions processing the incoming information are adapted to the reception of fundamentally different sensory cues has not been investigated in hemimetabolous insects. Here we describe the antennal sensilla, the general brain structure, and the antennal sensory pathways in the last six nymphal instars of Libellula depressa, in comparison with earlier published data from adults, using scanning electron microscopy, and antennal receptor neuron and antennal lobe output neuron mass-tracing with tetramethylrhodamin. Brain structure was visualized with an anti-synapsin antibody. Differently from adults, the nymphal antennal flagellum harbors many mechanoreceptive sensilla, one olfactory, and two thermo-hygroreceptive sensilla at all investigated instars. The nymphal brain is very similar to the adult brain throughout development, despite the considerable differences in antennal sensilla and habitat. Like in adults, nymphal brains contain mushroom bodies lacking calyces and small aglomerular antennal lobes. Antennal fibers innervate the antennal lobe similar to adult brains and the gnathal ganglion more prominently than in adults. Similar brain structures are thus used in L. depressa nymphs and adults to process diverging sensory information.
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Affiliation(s)
- Silvana Piersanti
- Dipartimento di Chimica, Biologia e Biotecnologie, University of Perugia, 06123 Perugia, Italy; (S.P.); (M.R.)
| | - Manuela Rebora
- Dipartimento di Chimica, Biologia e Biotecnologie, University of Perugia, 06123 Perugia, Italy; (S.P.); (M.R.)
| | - Gianandrea Salerno
- Dipartimento di Scienze Agrarie, Alimentari e Ambientali, University of Perugia, 06123 Perugia, Italy;
| | - Sylvia Anton
- IGEPP, INRAE, Institut Agro, Univ Rennes, 49045 Angers, France
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6
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Lv LY, Liang XF, He S. Genome-Wide Identification and Characterization of Olfactory Receptor Genes in Chinese Perch, Siniperca chuatsi. Genes (Basel) 2019; 10:E178. [PMID: 30823620 DOI: 10.3390/genes10020178] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2018] [Revised: 02/18/2019] [Accepted: 02/20/2019] [Indexed: 11/29/2022] Open
Abstract
Olfaction, which is mediated by olfactory receptor (OR) genes, is essential in the daily life of fish, especially in foraging. However, Chinese perch (Siniperca chuatsi) is believed to prey with reliance on vision and lateral sensation, but not on olfaction. Therefore, understanding the evolutionary dynamics of the Chinese perch OR repertoire could provide insights into genetic evidence for adapting to a decreasing reliance on olfaction. Here, we reported a whole-genome analysis of the Chinese perch OR repertoire. Our analysis identified a total of 152 OR genes, including 123 functional genes and 29 pseudogenes, and showed their genomic organization. A phylogenetic tree was constructed, and the phylogenetic relationships of teleosts ORs was illustrated. The dN/dS (global ratios of non-synonymous to synonymous) analysis demonstrated that OR groups all appeared to be under purifying selection. Among the five Percomorpha fishes, Chinese perch only had 22 subfamilies, suggesting a decrease in OR diversities. The species-specific loss of subfamily 56 and 66 in Chinese perch, of which the genes belonged to subfamily 66, were orthologs of OR51E2, which recognized the plant odorant β-ionone, indicating that extremely piscivorous fish which might lose those receptors responded to plant-related odors. Finally, the expression profiles of OR genes in the olfactory epithelium at different developmental stages were investigated using RNA-seq data. From the aforementioned results, the evolution of the OR repertoire may be shaped by the adaption of vision-dependent specializations for foraging in Chinese perch. The first systematic study of OR genes in Chinese perch could provide valuable genomic resources for the further investigation of olfactory function in teleosts.
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Rebora M, Frati F, Piersanti S, Salerno G, Selvaggini R, Fincke OM. Field tests of multiple sensory cues in sex recognition and harassment of a colour polymorphic damselfly. Anim Behav 2018; 136:127-136. [DOI: 10.1016/j.anbehav.2017.12.015] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Abstract
The larval antennal sensilla of two Zygoptera species, Calopteryx haemorroidalis (Calopterygidae) and Ischnura elegans (Coenagrionidae) are investigated with SEM and TEM. These two species have different antennae (geniculate, setaceous) and live in different environments (lotic, lentic waters). Notwithstanding this, similarities in the kind and distribution of sensilla are outlined: in both species the majority of sensilla types is located on the apical portion of the antenna, namely a composed coeloconic sensillum (possible chemoreceptor), two other coeloconic sensilla (possible thermo-hygroreceptors) and an apical seta (direct contact mechanoreceptor). Other mechanoreceptors, such as filiform hairs sensitive to movements of the surrounding medium or bristles positioned to sense the movements of the flagellar segments, are present on the antenna. Similarities in the antennal sensilla types and distribution are observed also with other dragonfly species, such as Onychogomphus forcipatus and Libellula depressa. A peculiar structure with an internal organization similar to that of a gland is observed in the apical antenna of C. haemorroidalis and I. elegans and it is present also in O. forcipatus and L. depressa. The possible function of this structure is at the moment unknown but deserves further investigations owing to its widespread presence in Odonata larvae.
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Affiliation(s)
- Silvana Piersanti
- Dipartimento di Chimica, Biologia e Biotecnologie, University of Perugia, Via Elce di Sotto, 1, 06121 Perugia, Italy.
| | - Manuela Rebora
- Dipartimento di Chimica, Biologia e Biotecnologie, University of Perugia, Via Elce di Sotto, 1, 06121 Perugia, Italy
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9
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Ioannidis P, Simao FA, Waterhouse RM, Manni M, Seppey M, Robertson HM, Misof B, Niehuis O, Zdobnov EM. Genomic Features of the Damselfly Calopteryx splendens Representing a Sister Clade to Most Insect Orders. Genome Biol Evol 2017; 9:415-430. [PMID: 28137743 PMCID: PMC5381652 DOI: 10.1093/gbe/evx006] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/19/2017] [Indexed: 12/14/2022] Open
Abstract
Insects comprise the most diverse and successful animal group with over one million described species that are found in almost every terrestrial and limnic habitat, with many being used as important models in genetics, ecology, and evolutionary research. Genome sequencing projects have greatly expanded the sampling of species from many insect orders, but genomic resources for species of certain insect lineages have remained relatively limited to date. To address this paucity, we sequenced the genome of the banded demoiselle, Calopteryx splendens, a damselfly (Odonata: Zygoptera) belonging to Palaeoptera, the clade containing the first winged insects. The 1.6 Gbp C. splendens draft genome assembly is one of the largest insect genomes sequenced to date and encodes a predicted set of 22,523 protein-coding genes. Comparative genomic analyses with other sequenced insects identified a relatively small repertoire of C. splendens detoxification genes, which could explain its previously noted sensitivity to habitat pollution. Intriguingly, this repertoire includes a cytochrome P450 gene not previously described in any insect genome. The C. splendens immune gene repertoire appears relatively complete and features several genes encoding novel multi-domain peptidoglycan recognition proteins. Analysis of chemosensory genes revealed the presence of both gustatory and ionotropic receptors, as well as the insect odorant receptor coreceptor gene (OrCo) and at least four partner odorant receptors (ORs). This represents the oldest known instance of a complete OrCo/OR system in insects, and provides the molecular underpinning for odonate olfaction. The C. splendens genome improves the sampling of insect lineages that diverged before the radiation of Holometabola and offers new opportunities for molecular-level evolutionary, ecological, and behavioral studies.
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Affiliation(s)
- Panagiotis Ioannidis
- Department of Genetic Medicine and Development, University of Geneva Medical School, Geneva, Switzerland.,Swiss Institute of Bioinformatics, Geneva, Switzerland
| | - Felipe A Simao
- Department of Genetic Medicine and Development, University of Geneva Medical School, Geneva, Switzerland.,Swiss Institute of Bioinformatics, Geneva, Switzerland
| | - Robert M Waterhouse
- Department of Genetic Medicine and Development, University of Geneva Medical School, Geneva, Switzerland.,Swiss Institute of Bioinformatics, Geneva, Switzerland
| | - Mosè Manni
- Department of Genetic Medicine and Development, University of Geneva Medical School, Geneva, Switzerland.,Swiss Institute of Bioinformatics, Geneva, Switzerland
| | - Mathieu Seppey
- Department of Genetic Medicine and Development, University of Geneva Medical School, Geneva, Switzerland.,Swiss Institute of Bioinformatics, Geneva, Switzerland
| | - Hugh M Robertson
- Department of Entomology, University of Illinois at Urbana-Champaign, Urbana, IL
| | - Bernhard Misof
- Center for Molecular Biodiversity Research, Zoological Research Museum Alexander Koenig, Bonn, Germany
| | - Oliver Niehuis
- Center for Molecular Biodiversity Research, Zoological Research Museum Alexander Koenig, Bonn, Germany
| | - Evgeny M Zdobnov
- Department of Genetic Medicine and Development, University of Geneva Medical School, Geneva, Switzerland.,Swiss Institute of Bioinformatics, Geneva, Switzerland
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Rebora M, Piersanti S, Frati F, Salerno G. Antennal responses to volatile organic compounds in a stonefly. J Insect Physiol 2017; 98:231-237. [PMID: 28115118 DOI: 10.1016/j.jinsphys.2017.01.011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Revised: 01/11/2017] [Accepted: 01/12/2017] [Indexed: 06/06/2023]
Abstract
Notwithstanding their long antennae, especially in the adult stage, Plecoptera represent a poorly studied group as regards their sensory structures and their ability to perceive olfactory stimuli is so far totally unknown. A recent investigation on the antenna of Dinocras cephalotes revealed two kinds of putative olfactory sensilla (multiporous single walled sensilla and digitated double walled sensilla). The present electrophysiological study (electroantennography, EAG), in which male and female antennae of D. cephalotes (Plecoptera, Perlidae) have been stimulated with a set of generic odours belonging to different functional groups, shows that Plecoptera can perceive olfactory cues through their antennal sensilla. Indeed, although many chemicals did not elicit any response, high EAG activity has been recorded in response to pentanoic acid, propanal, butyric acid, propionic acid, isoamylamine and ammonia. The response was very similar in both sexes even if propanal elicited a response only in males. EAG dose-responses curves in both males and females showed that EAG responses were similar in males and females and generally increased in amplitude with increasing doses of the chemicals. Behavioural, neuroanatomical and molecular investigations on Plecoptera olfaction, could be particularly interesting not only to increase the knowledge of the adult stonefly behaviour but also to better understand the adaptation of the olfactory sensory system in aquatic insects moving from land to water.
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Affiliation(s)
- Manuela Rebora
- Dipartimento di Chimica, Biologia e Biotecnologie, University of Perugia, Italy
| | - Silvana Piersanti
- Dipartimento di Chimica, Biologia e Biotecnologie, University of Perugia, Italy.
| | - Francesca Frati
- Dipartimento di Scienze Agrarie, Alimentari e Ambientali, University of Perugia, Italy
| | - Gianandrea Salerno
- Dipartimento di Scienze Agrarie, Alimentari e Ambientali, University of Perugia, Italy
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Abstract
Beetles comprise about 400,000 described species, nearly one third of all known animal species. The enormous success of the order Coleoptera is reflected by a rich diversity of lifestyles, behaviors, morphological, and physiological adaptions. All these evolutionary adaptions that have been driven by a variety of parameters over the last about 300 million years, make the Coleoptera an ideal field to study the evolution of the brain on the interface between the basic bauplan of the insect brain and the adaptions that occurred. In the current study we concentrated on the paired antennal lobes (AL), the part of the brain that is typically responsible for the first processing of olfactory information collected from olfactory sensilla on antenna and mouthparts. We analyzed 63 beetle species from 22 different families and thus provide an extensive comparison of principal neuroarchitecture of the AL. On the examined anatomical level, we found a broad diversity including AL containing a wide range of glomeruli numbers reaching from 50 to 150 glomeruli and several species with numerous small glomeruli, resembling the microglomerular design described in acridid grasshoppers and diving beetles, and substructures within the glomeruli that have to date only been described for the small hive beetle, Aethina tumida. A first comparison of the various anatomical features of the AL with available descriptions of lifestyle and behaviors did so far not reveal useful correlations. In summary, the current study provides a solid basis for further studies to unravel mechanisms that are basic to evolutionary adaptions of the insect olfactory system.
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Affiliation(s)
- Martin Kollmann
- Department of Biology—Animal Physiology, Philipps-University Marburg, Marburg, Germany
| | - Rovenna Schmidt
- Department of Biology—Animal Physiology, Philipps-University Marburg, Marburg, Germany
- Institute of Veterinary Anatomy, Histology and Embryology, Justus-Liebig University Gießen, Gießen, Germany
| | - Carsten M. Heuer
- Department of Biology—Animal Physiology, Philipps-University Marburg, Marburg, Germany
- Fraunhofer-Institut für Naturwissenschaftlich-Technische Trendanalysen INT, Euskirchen, Germany
| | - Joachim Schachtner
- Department of Biology—Animal Physiology, Philipps-University Marburg, Marburg, Germany
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12
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Rebora M, Tierno de Figueroa JM, Piersanti S. Antennal sensilla of the stonefly Dinocras cephalotes (Plecoptera: Perlidae). Arthropod Struct Dev 2016; 45:552-561. [PMID: 27742465 DOI: 10.1016/j.asd.2016.10.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Revised: 10/06/2016] [Accepted: 10/07/2016] [Indexed: 06/06/2023]
Abstract
Plecoptera, one of the most primitive groups of Neoptera, are important aquatic insects usually employed as bioindicators of high water quality. Notwithstanding the well-developed antennae of the adult, its sensory abilities are so far not well known. The present paper describes at ultrastructural level under scanning and transmission electron microscopy the antennal sensilla of the adult stonefly Dinocras cephalotes (Plecoptera, Perlidae). Adult males and females show a filiform antenna constituted of a scape, a pedicel and a flagellum composed of very numerous segments with no clear sexual dimorphism in the number and distribution of the antennal sensilla. The most represented sensilla are sensilla trichodea, with different length, whose internal structure reveal their mechanosensory function, sensilla chaetica, with an apical pore, with an internal structure revealing a typical gustatory function, porous pegs representing single-walled olfactory sensilla, digitated pegs with hollow cuticular spoke channels representing double-walled olfactory sensilla, pegs in pits for which we hypothesize a thermo-hygrosensory function. The diversity of described sensilla is discussed in relation to known biological aspects of the studied species. This opens new perspectives in the study of the behavior of these aquatic insects during their adult stage.
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Affiliation(s)
- Manuela Rebora
- Dipartimento di Chimica, Biologia e Biotecnologie, University of Perugia, 06121, Italy.
| | | | - Silvana Piersanti
- Dipartimento di Chimica, Biologia e Biotecnologie, University of Perugia, 06121, Italy
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13
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Bybee S, Córdoba-Aguilar A, Duryea MC, Futahashi R, Hansson B, Lorenzo-Carballa MO, Schilder R, Stoks R, Suvorov A, Svensson EI, Swaegers J, Takahashi Y, Watts PC, Wellenreuther M. Odonata (dragonflies and damselflies) as a bridge between ecology and evolutionary genomics. Front Zool 2016; 13:46. [PMID: 27766110 PMCID: PMC5057408 DOI: 10.1186/s12983-016-0176-7] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Accepted: 09/16/2016] [Indexed: 12/21/2022] Open
Abstract
Odonata (dragonflies and damselflies) present an unparalleled insect model to integrate evolutionary genomics with ecology for the study of insect evolution. Key features of Odonata include their ancient phylogenetic position, extensive phenotypic and ecological diversity, several unique evolutionary innovations, ease of study in the wild and usefulness as bioindicators for freshwater ecosystems worldwide. In this review, we synthesize studies on the evolution, ecology and physiology of odonates, highlighting those areas where the integration of ecology with genomics would yield significant insights into the evolutionary processes that would not be gained easily by working on other animal groups. We argue that the unique features of this group combined with their complex life cycle, flight behaviour, diversity in ecological niches and their sensitivity to anthropogenic change make odonates a promising and fruitful taxon for genomics focused research. Future areas of research that deserve increased attention are also briefly outlined.
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Affiliation(s)
- Seth Bybee
- Brigham Young University, Provo, UT 84606 USA
| | - Alex Córdoba-Aguilar
- Departmento de Ecología Evolutiva, Instituto de Ecología, Universidad Nacional Autónoma de México, Apdo, Postal 70-275, Ciudad Universitaria, 04510 Mexico City, Mexico
| | - M. Catherine Duryea
- Evolutionary Ecology Unit, Department of Biology, Lund University, 223 62 Lund, Sweden
| | - Ryo Futahashi
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology, Central 6, Tsukuba, Ibaraki 305-8566 Japan
| | - Bengt Hansson
- Evolutionary Ecology Unit, Department of Biology, Lund University, 223 62 Lund, Sweden
| | - M. Olalla Lorenzo-Carballa
- Institute of Integrative Biology, Biosciences Building, University of Liverpool, Crown Street, Liverpool, L69 7ZB UK
| | - Ruud Schilder
- Departments of Entomology and Biology, Pennsylvania State University, University Park, PA 16802 USA
| | - Robby Stoks
- Laboratory of Aquatic Ecology, Evolution and Conservation, Department of Biology, University of Leuven, 3000 Leuven, Belgium
| | - Anton Suvorov
- Department of Biology, Brigham Young University, LSB 4102, Provo, UT 84602 USA
| | - Erik I. Svensson
- Evolutionary Ecology Unit, Department of Biology, Lund University, 223 62 Lund, Sweden
| | - Janne Swaegers
- Laboratory of Aquatic Ecology, Evolution and Conservation, Department of Biology, University of Leuven, 3000 Leuven, Belgium
| | - Yuma Takahashi
- Division of Ecology and Evolutionary Biology, Graduate School of Life Sciences, Tohoku University, 6-3, Aoba, Aramaki, Aoba, Sendai, Miyagi 980-8578 Japan
| | | | - Maren Wellenreuther
- Evolutionary Ecology Unit, Department of Biology, Lund University, 223 62 Lund, Sweden
- Plant and Food Research Limited, Nelson, 7010 New Zealand
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14
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Futahashi R. Color vision and color formation in dragonflies. Curr Opin Insect Sci 2016; 17:32-39. [PMID: 27720071 DOI: 10.1016/j.cois.2016.05.014] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Revised: 05/20/2016] [Accepted: 05/21/2016] [Indexed: 06/06/2023]
Abstract
Dragonflies including damselflies are colorful and large-eyed insects, which show remarkable sexual dimorphism, color transition, and color polymorphism. Recent comprehensive visual transcriptomics has unveiled an extraordinary diversity of opsin genes within the lineage of dragonflies. These opsin genes are differentially expressed between aquatic larvae and terrestrial adults, as well as between dorsal and ventral regions of adult compound eyes. Recent topics of color formation in dragonflies are also outlined. Non-iridescent blue color is caused by coherent light scattering from the quasiordered nanostructures, whereas iridescent color is produced by multilayer structures. Wrinkles or wax crystals sometimes enhances multilayer structural colors. Sex-specific and stage-specific color differences in red dragonflies is attributed to redox states of ommochrome pigments.
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Affiliation(s)
- Ryo Futahashi
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Central 6, Tsukuba, Ibaraki 305-8566, Japan.
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15
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Frati F, Piersanti S, Rebora M, Salerno G. Volatile cues can drive the oviposition behavior in Odonata. J Insect Physiol 2016; 91-92:34-38. [PMID: 27349728 DOI: 10.1016/j.jinsphys.2016.06.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Revised: 06/22/2016] [Accepted: 06/23/2016] [Indexed: 06/06/2023]
Abstract
Selection for the oviposition site represents the criterion for the behavioral process of habitat selection for the next generation. It is well known that in Odonata the most general cues are detected visually, but laboratory investigations on the coenagrionid Ischnura elegans showed through behavioral and electrophysiological assays that adults were attracted by olfactory cues emitted by prey and that males of the same species are attracted by female odor. The results of the present behavioral and electrophysiological investigations on I. elegans suggest the involvement of antennal olfactory sensilla in oviposition behavior. In particular, I. elegans females laid in the laboratory significantly more eggs in water from larval rearing aquaria than in distilled or tap water. Moreover, the lack of preference between rearing water and tap water with plankton suggests a role of volatiles related to conspecific and plankton presence in the oviposition site choice. I. elegans may rely on food odor for oviposition site selection, thus supporting the predictions of the "mother knows best" theory. These behavioral data are partially supported by electroantennographic responses. These findings confirm a possible role of olfaction in crucial aspects of Odonata biology.
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Affiliation(s)
- Francesca Frati
- Dipartimento di Scienze Agrarie, Alimentari e Ambientali, University of Perugia, Italy
| | - Silvana Piersanti
- Dipartimento di Chimica, Biologia e Biotecnologie, University of Perugia, Italy.
| | - Manuela Rebora
- Dipartimento di Chimica, Biologia e Biotecnologie, University of Perugia, Italy
| | - Gianandrea Salerno
- Dipartimento di Scienze Agrarie, Alimentari e Ambientali, University of Perugia, Italy
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16
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Piersanti S, Frati F, Rebora M, Salerno G. Carbon dioxide detection in adult Odonata. ZOOLOGY 2016; 119:137-142. [PMID: 26831359 DOI: 10.1016/j.zool.2016.01.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2015] [Revised: 11/26/2015] [Accepted: 01/10/2016] [Indexed: 12/27/2022]
Abstract
The present paper shows, by means of single-cell recordings, responses of antennal sensory neurons of the damselfly Ischnura elegans when stimulated by air streams at different CO2 concentrations. Unlike most insects, but similarly to termites, centipedes and ticks, Odonata possess sensory neurons strongly inhibited by CO2, with the magnitude of the off-response depending upon the CO2 concentration. The Odonata antennal sensory neurons responding to CO2 are also sensitive to airborne odors; in particular, the impulse frequency is increased by isoamylamine and decreased by heptanoic and pentanoic acid. Further behavioral investigations are necessary to assign a biological role to carbon dioxide detection in Odonata.
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Affiliation(s)
- Silvana Piersanti
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, Via Elce di Sotto, 06123 Perugia, Italy.
| | - Francesca Frati
- Dipartimento di Scienze Agrarie, Alimentari e Ambientali, Università degli Studi di Perugia, Borgo XX Giugno, 74, 06121 Perugia, Italy
| | - Manuela Rebora
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, Via Elce di Sotto, 06123 Perugia, Italy
| | - Gianandrea Salerno
- Dipartimento di Scienze Agrarie, Alimentari e Ambientali, Università degli Studi di Perugia, Borgo XX Giugno, 74, 06121 Perugia, Italy
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17
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Siepielski AM, Fallon E, Boersma K. Predator olfactory cues generate a foraging-predation trade-off through prey apprehension. R Soc Open Sci 2016; 3:150537. [PMID: 26998324 PMCID: PMC4785975 DOI: 10.1098/rsos.150537] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/07/2015] [Accepted: 01/08/2016] [Indexed: 06/05/2023]
Abstract
Most animals are faced with the challenge of securing food under the risk of predation. This frequently generates a trade-off whereby animals respond to predator cues with reduced movement to avoid predation at the direct cost of reduced foraging success. However, predators may also cause prey to be apprehensive in their foraging activities, which would generate an indirect 'apprehension cost'. Apprehension arises when a forager redirects attention from foraging tasks to predator detection and incurs a cost from such multi-tasking, because the forager ends up making more mistakes in its foraging tasks as a result. Here, we test this apprehension cost hypothesis and show that damselflies miss a greater proportion of their prey during foraging bouts in response to both olfactory cues produced by conspecifics that have only viewed a fish predator and olfactory cues produced directly by fish. This reduced feeding efficiency is in addition to the stereotypical anti-predator response of reduced activity, which we also observed. These results show that costs associated with anti-predator responses not only arise through behavioural alterations that reduce the risk of predation, but also from the indirect costs of apprehension and multi-tasking that can reduce feeding efficiency under the threat of predation.
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18
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Frati F, Piersanti S, Conti E, Rebora M, Salerno G. Scent of a Dragonfly: Sex Recognition in a Polymorphic Coenagrionid. PLoS One 2015; 10:e0136697. [PMID: 26305118 DOI: 10.1371/journal.pone.0136697] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2015] [Accepted: 08/05/2015] [Indexed: 01/26/2023] Open
Abstract
In polymorphic damselflies discrimination of females from males is complex owing to the presence of androchrome and gynochrome females. To date there is no evidence that damselflies use sensory modalities other than vision (and tactile stimuli) in mate searching and sex recognition. The results of the present behavioural and electrophysiological investigations on Ischnura elegans, a polymorphic damselfly, support our hypothesis that chemical cues could be involved in Odonata sex recognition. The bioassays demonstrate that males in laboratory prefer female to male odour, while no significant difference was present in male behavior between stimuli from males and control. The bioassays suggest also some ability of males to distinguish between the two female morphs using chemical stimuli. The ability of male antennae to perceive odours from females has been confirmed by electrophysiological recordings. These findings are important not only to get insight into the chemical ecology of Odonata, and to shed light into the problem of olfaction in Paleoptera, but could be useful to clarify the controversial aspects of the mating behavior of polymorphic coenagrionids. Behavioural studies in the field are necessary to investigate further these aspects.
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19
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Fincke OM. Trade-offs in female signal apparency to males offer alternative anti-harassment strategies for colour polymorphic females. J Evol Biol 2015; 28:931-43. [PMID: 25786740 DOI: 10.1111/jeb.12623] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2014] [Revised: 03/10/2015] [Accepted: 03/12/2015] [Indexed: 01/22/2023]
Abstract
Colour polymorphisms are known to influence receiver behaviour, but how they affect a receiver's ability to detect and recognize individuals in nature is usually unknown. I hypothesized that polymorphic female damselflies represent an evolutionary stable strategy, maintained by trade-offs between the relative apparency of morphs to male receivers. Using field experiments on Enallagma hageni and focal studies of E. hageni and Enallagma boreale, I tested for the first time the predictions that (i) green heteromorphs and blue andromorphs gain differential protection from sexual harassment via background crypsis and sexual mimicry, respectively, and (ii) female morphs behaviourally optimize their signal apparency to mate-searching males. First, based on male reactions elicited by females, against a high-contrast background, the two morphs did not differ in being detected by males, and once detected, they did not differ in being recognized (eliciting sexual reactions). However, on green ferns, heteromorphs were less likely to be detected (elicited only fly-bys) than andromorphs, but once detected, the morphs did not differ in being recognized. In contrast, when perched on a dowel with two male signal distractors, andromorphs were detected less often, and once detected, they were recognized less often than heteromorphs. Second, in fields where females foraged, andromorphs perched higher on vegetation than heteromorphs and were more often in the vicinity of males. Neither harassment rates nor evasive behaviours differed between morphs. Males aggregated in high density near shore where solitary females were rare. Equilibrium frequencies of these and other colour morphs should reflect the relative ease with which receivers detect and recognize them in the context where they are encountered.
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Affiliation(s)
- O M Fincke
- Ecology and Evolutionary Biology Graduate Program, Department of Biology, University of Oklahoma Norman, Norman, OK, USA
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20
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Piersanti S, Frati F, Conti E, Rebora M, Salerno G. The sense of smell in Odonata: an electrophysiological screening. J Insect Physiol 2014; 70:49-58. [PMID: 25218659 DOI: 10.1016/j.jinsphys.2014.09.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2014] [Revised: 08/11/2014] [Accepted: 09/03/2014] [Indexed: 06/03/2023]
Abstract
Volatile chemicals mediate a great range of intra- and interspecific signalling and information in insects. Olfaction has been widely investigated mostly in Neoptera while the knowledge of this sense in most basal insects such as Paleoptera (Odonata and Ephemeroptera) is still poor. In the present study we show the results of an electrophysiological screening on two model species, Libellula depressa (Libellulidae) and Ischnura elegans (Coenagrionidae), representatives of the two Odonata suborders Anisoptera and Zygoptera, with the aim to deep the knowledge on the sense of smell of this insect order. The antennal olfactory sensory neurons (OSNs) of these two species responded to the same 22 compounds (out of 48 chemicals belonging to different functional groups) encompassing mostly amines, carboxylic acids or aldehydes and belonging to green leaf volatiles, vertebrate related volatiles and volatiles emitted by standing waters bacteria. The properties of Odonata OSNs are very similar to those of ionotropic receptors (IRs) expressing OSNs in other insects.
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Affiliation(s)
- Silvana Piersanti
- Dipartimento di Chimica, Biologia e Biotecnologie, University of Perugia, Italy
| | - Francesca Frati
- Dipartimento di Scienze Agrarie, Alimentari e Ambientali, University of Perugia, Italy
| | - Eric Conti
- Dipartimento di Scienze Agrarie, Alimentari e Ambientali, University of Perugia, Italy
| | - Manuela Rebora
- Dipartimento di Chimica, Biologia e Biotecnologie, University of Perugia, Italy.
| | - Gianandrea Salerno
- Dipartimento di Scienze Agrarie, Alimentari e Ambientali, University of Perugia, Italy
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Chauhan P, Hansson B, Kraaijeveld K, de Knijff P, Svensson EI, Wellenreuther M. De novo transcriptome of Ischnura elegans provides insights into sensory biology, colour and vision genes. BMC Genomics 2014; 15:808. [PMID: 25245033 PMCID: PMC4182773 DOI: 10.1186/1471-2164-15-808] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2014] [Accepted: 09/09/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND There is growing interest in odonates (damselflies and dragonflies) as model organisms in ecology and evolutionary biology but the development of genomic resources has been slow. So far only one draft genome (Ladona fulva) and one transcriptome assembly (Enallagma hageni) have been published. Odonates have some of the most advanced visual systems among insects and several species are colour polymorphic, and genomic and transcriptomic data would allow studying the genomic architecture of these interesting traits and make detailed comparative studies between related species possible. Here, we present a comprehensive de novo transcriptome assembly for the blue-tailed damselfly Ischnura elegans (Odonata: Coenagrionidae) built from short-read RNA-seq data. The transcriptome analysis in this paper provides a first step towards identifying genes and pathways underlying the visual and colour systems in this insect group. RESULTS Illumina RNA sequencing performed on tissues from the head, thorax and abdomen generated 428,744,100 paired-ends reads amounting to 110 Gb of sequence data, which was assembled de novo with Trinity. A transcriptome was produced after filtering and quality checking yielding a final set of 60,232 high quality transcripts for analysis. CEGMA software identified 247 out of 248 ultra-conserved core proteins as 'complete' in the transcriptome assembly, yielding a completeness of 99.6%. BLASTX and InterProScan annotated 55% of the assembled transcripts and showed that the three tissue types differed both qualitatively and quantitatively in I. elegans. Differential expression identified 8,625 transcripts to be differentially expressed in head, thorax and abdomen. Targeted analyses of vision and colour functional pathways identified the presence of four different opsin types and three pigmentation pathways. We also identified transcripts involved in temperature sensitivity, thermoregulation and olfaction. All these traits and their associated transcripts are of considerable ecological and evolutionary interest for this and other insect orders. CONCLUSIONS Our work presents a comprehensive transcriptome resource for the ancient insect order Odonata and provides insight into their biology and physiology. The transcriptomic resource can provide a foundation for future investigations into this diverse group, including the evolution of colour, vision, olfaction and thermal adaptation.
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Affiliation(s)
- Pallavi Chauhan
- />Department of Biology, Lund University, Sölvegatan 37, SE 22362 Lund, Sweden
| | - Bengt Hansson
- />Department of Biology, Lund University, Sölvegatan 37, SE 22362 Lund, Sweden
| | - Ken Kraaijeveld
- />Animal Ecology, Department of Ecological Science, VU University Amsterdam, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands
- />Department of Human and Clinical Genetics, Leiden University Medical Center, PO Box 9600, 2300 RC Leiden, The Netherlands
| | - Peter de Knijff
- />Department of Human and Clinical Genetics, Leiden University Medical Center, PO Box 9600, 2300 RC Leiden, The Netherlands
| | - Erik I Svensson
- />Department of Biology, Lund University, Sölvegatan 37, SE 22362 Lund, Sweden
| | - Maren Wellenreuther
- />Department of Biology, Lund University, Sölvegatan 37, SE 22362 Lund, Sweden
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Rebora M, Gaino E, Piersanti S. The epipharyngeal sensilla of the damselfly Ischnura elegans (Odonata, Coenagrionidae). Micron 2014; 66:31-6. [PMID: 25080274 DOI: 10.1016/j.micron.2014.05.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2014] [Revised: 05/07/2014] [Accepted: 05/19/2014] [Indexed: 10/25/2022]
Abstract
The knowledge on Odonata adult mouthparts sensilla is scanty and, notwithstanding the epipharynx in the labrum is considered an organ of taste, no ultrastructural investigation has been performed so far on this structure in Odonata. The labrum of the adult of the damselfly Ischnura elegans (Odonata, Coenagrionidae) shows on its ventral side the epipharynx with sensilla represented by articulated hairs and by small pegs located at the apex of slightly raised domes. Under scanning and transmission electron microscope, the articulated hairs, with a well developed socket and tubular body, have the typical structure of bristles, the most common type of insect mechanoreceptors, usually responding to direct touch; the pegs, showing an apical pore together with a variable number of sensory neurons (from two to five), the outer dendritic segments of which show a dendrite sheath stopping along their length, have features typical of contact chemoreceptors.
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Affiliation(s)
- Manuela Rebora
- Dipartimento di Chimica, Biologia e Biotecnologie, Università di Perugia, Via Elce di Sotto, 06121 Perugia, Italy.
| | - Elda Gaino
- Dipartimento di Chimica, Biologia e Biotecnologie, Università di Perugia, Via Elce di Sotto, 06121 Perugia, Italy
| | - Silvana Piersanti
- Dipartimento di Chimica, Biologia e Biotecnologie, Università di Perugia, Via Elce di Sotto, 06121 Perugia, Italy
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