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1.
Arthropod Struct Dev ; 77: 101311, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37852030

RESUMO

Systematic issues regarding Plecoptera are still debated, and the molecular data seem to be unable to definitively clarify the relationships within the order. Spermatozoa are under constant evolutionary pressure, and comparative spermatology can be useful in carrying systematic and phylogenetic information. In the present paper we describe the sperm structure, using light, scanning and transmission electron and immunofluorescence microscopy, of six Euholognatha species belonging to genera not analyzed in our previous studies, i.e. Capnopsis, Amphinemura, Rhabdiopteryx, Tyrrhenoleuctra, Zwicknia and Protonemura. The spermatozoa of all the species examined are fîliform and have a flagellum characterized by an axoneme with 9 + 9+2 pattern and two mitochondrial derivatives. Their ultrastructure shows a degree of heterogeneity within the order. On the contrary, morphological features of sperm are well conserved inside a single Euholognathan family, and the species share a general family sperm model, even if different interspecific or intergeneric characters can be identified and used for systematic inferences. Among Nemouroidea, Taeniopterygidae, showing a peculiar sperm model, seems to have an isolated phylogenetic position. Nemouridae, with a mono-layered acrosome, are isolated among the remaining families, while we can hypothesize a sister taxa relationship between Leuctridae and Capniidae. As regards Perloidea, the sperm characters suggest a closer relationship between Chloroperlidae and Perlodidae, rather than between Perlidae and Perlodidae, as commonly hypothesized.


Assuntos
Insetos , Sêmen , Humanos , Masculino , Animais , Filogenia , Espermatozoides/ultraestrutura , Acrossomo/ultraestrutura , Neópteros
2.
Zootaxa ; 5315(4): 329-338, 2023 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-37518596

RESUMO

In this paper we present the results of a study of different populations of the genus Tyrrhenoleuctra, which includes morphologically cryptic species, in the Iberian Peninsula. A total of six populations were analysed from a molecular point of view and a behavioural study was conducted on three of them. Two phylogenetic trees, maximum likelihood (ML) and neighbour joining (NJ), were constructed using both new COI sequences and COI sequences already available in GenBank. Furthermore, intra- and interspecific p-distances were calculated within and between sequences of the different populations. As regards behavioural analyses, the male call of individuals from three of the studied populations was recorded, analysed and described. Both phylogenetic approaches used, ML and NJ, were congruent in discriminating five well-defined clusters, representing the four known Iberian Tyrrhenoleuctra species and a previously unknown taxon. The sequences from the six studied populations produced in this study fell within two clades: T. lusohispanica (four populations) and the new taxon (two populations). These results were supported also by the behavioral study, in which the drumming calls of individuals belonging to the two clades differed in some important parameters such as the number of sequences, intersequence interval and interbeat interval. The obtained results expand the previously known distribution of T. lusohispanica and show the existence of a new species (Tyrrhenoleuctra hynesi sp. n.) within this genus from a more restricted area, that will be described in this paper.

3.
J Med Entomol ; 59(2): 772-776, 2022 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-34971396

RESUMO

Biting midges of the genus Culicoides (Diptera: Ceratopogonidae) play a paramount role in medical and veterinary entomology worldwide, particularly as vectors of pathogens which cause animal diseases. Biting midges are also infamous for the nuisance they provoke to people involved in outdoor activities. Nonetheless, attacks to man by midges from any Culicoides species have not been reported in Italy. An entomological investigation was performed following repeated attacks to man in a nature park near Rome (central Italy). The study area is a natural degassing zone, characterized by widespread hazardous gas emissions of CO2 and H2S, with several water bodies including permanent lakes, ponds, and pools. The biting midge C. riethi Kieffer, 1914 was very active during daytime in the period April-June. The species has been identified as responsible for attacks on people in the area. An in-depth analysis of the extreme environmental conditions revealed the ability of larvae to thrive in several water bodies, characterized by an extremely low pH and a high concentration of sulfates.


Assuntos
Ceratopogonidae , Animais , Cruzamento , Humanos , Insetos Vetores , Itália , Larva , Água
4.
Zootaxa ; 4722(4): zootaxa.4722.4.7, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-32230619

RESUMO

Remarks on the endemicity of the Italian stonefly-fauna are presented. Notes on conservation issues are also given, together with the updated list of stoneflies of Italy.


Assuntos
Insetos , Animais , Itália
5.
Zootaxa ; 4661(3): zootaxa.4661.3.4, 2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31716698

RESUMO

The recent report of Nemoura lacustris Pictet, 1865 in Great Britain has raised doubts on its identity, given the isolation with respect to the Mediterranean and continental populations of this species. Using molecular analyses, we tested if populations from  the United Kingdom and the Iberian Peninsula were conspecific and tested the hypotheses of a recent colonization event versus a more ancient origin for the British populations. Phylogenetic analysis of the mitochondrial marker COI allowed us to conclude that the United Kingdom specimens morphologically ascribed to N. lacustris were conspecific with populations from France and the Iberian Peninsula. Based on the genetic divergence of the two reciprocally monophyletic clades from the Iberian Peninsula and Great Britain/France, respectively, the present distribution of N. lacustris can be postulated as a relatively recent dispersal or introduction into Great Britain from France.                Finally, we note the isolated position displayed by N. lacustris in the phylogenetic tree of Nemoura species based on COI sequences, as the sister to all included species of the genus. This isolated position corresponds with the specific morphology of N. lacustris genitalia and requires additional studies to ascertain clearer generic boundaries within the Nemouridae.


Assuntos
DNA Mitocondrial , Neópteros , Animais , Europa (Continente) , França , Variação Genética , Neópteros/genética , Filogenia , Reino Unido
6.
Zootaxa ; 4269(3): 447-450, 2017 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-28610329

RESUMO

Two new species belonging to the family Nemouridae, Nemoura kontumensis sp. nov. and Amphinemura konplongensis sp. nov. are described from the Central Highlands of Vietnam. Remarks on the affinities with related species are given.


Assuntos
Mariposas , Distribuição Animal , Animais , Vietnã
7.
Zootaxa ; 4121(1): 85-8, 2016 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-27395208

RESUMO

The amphinemurine genus Indonemoura Baumann (1975) was proposed for species previously included in the genera Protonemura Kempny and Nemoura Latreille. Baumann (1975) designated P. indica Kimmins, 1947 (in Kimmins 1946) as the type species. He also transferred 14 additional species from Protonemura and Nemoura into this genus. The genus is distributed mainly in the Oriental region (only one species from Tibet, close to the eastern border of the Palaearctic Region) and many new species have been added in the last decades (Zwick & Sivec 1980; Shimizu 1994a & b; Zhu et al. 2002; Li et al. 2005; Li & Yang 2005, 2006; Wang et al. 2006; Sivec & Stark 2010) including presently 53 species (DeWalt et al. 2009). Sivec & Stark (2010) first described three Indonemoura species from Vietnam, I. angulata, I. clavata, and I. tricantha. These three species are the only Indonemoura presently known for Vietnam.


Assuntos
Mariposas/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Tamanho Corporal , Feminino , Masculino , Mariposas/anatomia & histologia , Mariposas/crescimento & desenvolvimento , Tamanho do Órgão , Tibet , Vietnã
8.
Zootaxa ; 3764: 587-93, 2014 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-24870658

RESUMO

Tyrrhenoleuctra lusohispanica sp. n., a new species of the leuctrid genus Tyrrhenoleuctra from the southern Iberian Peninsula (southern Portugal and Spain) is described solely on molecular characters. Molecular analyses clearly indicated the distinctness of this species and demonstrated the presence of cryptic species in the genus Tyrrhenoleuctra. We also describe the systematic affinities of T. lusohispanica sp. n. to other species in the genus. With all Tyrrhenoleuctra species, T. lusohispanica sp. n. exhibits marked phenotypic variability.


Assuntos
Insetos/classificação , Animais , Feminino , Insetos/anatomia & histologia , Masculino , Filogenia , Espanha
9.
PLoS One ; 7(5): e36881, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22649502

RESUMO

The number of described species on the planet is about 1.9 million, with ca. 17,000 new species described annually, mostly from the tropics. However, taxonomy is usually described as a science in crisis, lacking manpower and funding, a politically acknowledged problem known as the Taxonomic Impediment. Using data from the Fauna Europaea database and the Zoological Record, we show that contrary to general belief, developed and heavily-studied parts of the world are important reservoirs of unknown species. In Europe, new species of multicellular terrestrial and freshwater animals are being discovered and named at an unprecedented rate: since the 1950s, more than 770 new species are on average described each year from Europe, which add to the 125,000 terrestrial and freshwater multicellular species already known in this region. There is no sign of having reached a plateau that would allow for the assessment of the magnitude of European biodiversity. More remarkably, over 60% of these new species are described by non-professional taxonomists. Amateurs are recognized as an essential part of the workforce in ecology and astronomy, but the magnitude of non-professional taxonomist contributions to alpha-taxonomy has not been fully realized until now. Our results stress the importance of developing a system that better supports and guides this formidable workforce, as we seek to overcome the Taxonomic Impediment and speed up the process of describing the planetary biodiversity before it is too late.


Assuntos
Biodiversidade , Classificação/métodos , Pesquisa , Animais , Europa (Continente) , Especificidade da Espécie
10.
J Insect Sci ; 11: 153, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22236413

RESUMO

The specific role of hemocyanin in Plecoptera (stoneflies) is still not completely understood, since none of the hypotheses advanced have proven fully convincing. Previous data show that mRNA hemocyanin sequences are not present in all Plecoptera, and that hemocyanin does not seem to be uniformly distributed within the order. All species possess hexamerins, which are multifunction proteins that probably originated from hemocyanin. In order to obtain an increasingly detailed picture on the presence and distribution of hemocyanin across the order, this study presents new data regarding nymphs and adults of selected Plecoptera species. Results confirm that the hemocyanin expression differs among nymphs in the studied stonefly species. Even though previous studies have found hemocyanin in adults of two stonefly species it was not detected in the present study, even in species where nymphs show hemocyanin, suggesting that the physiological need of this protein can change during life cycle. The phylogenetic pattern obtained using hemocyanin sequences matches the accepted scheme of traditional phylogeny based on morphology, anatomy, and biology. It is remarkable to note that the hemocyanin conserved region acts like a phylogenetic molecular marker within Plecoptera.


Assuntos
Hemocianinas/genética , Insetos/genética , Sequência de Aminoácidos , Animais , Hemocianinas/metabolismo , Insetos/metabolismo , Dados de Sequência Molecular , Ninfa/metabolismo , Análise de Sequência de DNA
11.
Protein J ; 25(7-8): 443-54, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17115256

RESUMO

We characterized two subunits of a putative haemocyanin from the stonefly species Perla grandis. In particular, we cloned and sequenced the corresponding cDNAs and studied their expression in different insect stages. Moreover, using the deduced amino acid sequences, homology studies were performed both on their primary and tertiary structures. 3-D molecular modelling data showed that the residues involved in the oxygen transport and subunits contacts were located in spatial positions preserving the functionality of the molecule. Despite it was paradigmatically affirmed that insects do not have respiratory proteins, our data suggest that the haemocyanin could be involved in the respiratory mechanisms of P. grandis. As far as we know, this is the first haemocyanin 3-D structure described and analyzed in insects.


Assuntos
Hemocianinas/química , Proteínas de Insetos/química , Insetos/metabolismo , Sequência de Aminoácidos , Animais , Clonagem Molecular , Hemocianinas/genética , Proteínas de Insetos/genética , Insetos/crescimento & desenvolvimento , Estágios do Ciclo de Vida , Modelos Moleculares , Dados de Sequência Molecular , Conformação Proteica , Subunidades Proteicas/química , Subunidades Proteicas/genética , Alinhamento de Sequência , Transcrição Gênica
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