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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Taksonomija i distribucija vrsta roda Merodon (Meigen, 1803) (Diptera: Syrphidae) u Palearktiku / Taxonomy and Distribution of the genus Merodon (Meigen, 1803) (Diptera: Syrphidae) in Palaeartic

Ačanski Jelena 24 May 2017 (has links)
<p>Predmet ovog istraživanja su vrste iz<em>&nbsp; Merodon&nbsp; aureus,&nbsp; M.&nbsp; nanus&nbsp; i&nbsp; M. ruficornis&nbsp; </em>grupe i&nbsp;<em> M.&nbsp; avidus&nbsp; </em>kompleksa sa područja Palearktika. Usled izuzetne morfolo&scaron;ke sličnosti pomenutih vrsta, kori&scaron;ćene su tri različite metode u cilju utvrđivanja&nbsp; prisustva skrivenih taksona i definisanja granica vrsta. Komparativnom geometerijsko-morfometrijskom analizom su obuhvaćene vrste iz&nbsp;<em> M.&nbsp; aureus&nbsp; i&nbsp; M.&nbsp;</em> <em>nanus&nbsp; </em>grupe i&nbsp;<em> M.&nbsp; avidus</em>&nbsp; kompleksa. Interspecijska varijabilnost&nbsp;<em> M.&nbsp; aureus</em>&nbsp; grupe i&nbsp;<em> M.&nbsp; avidus&nbsp;</em> kompleksa je analizirana sa dva geometrijsko-morfometrijska pristupa: analiza oblika krila -&nbsp; zasnovana na specifičnim tačkama (<em>landmarks</em>) i analiza oblika genitalnog aparata mužjaka&nbsp; -&nbsp; zasnovana na pomoćnim tačkama (<em>semilandmarks</em>).<br />Sredinske ni&scaron;e su kvantifikovane i poređene &ldquo;<em>Point base</em>&rdquo; metodom i njome su obuhvaćene sve istraživane vrste. Uslovljenost razlika u obliku krila i surstila analiziranih vrsta geografskom distribucijom i klimatskim faktorima je testirana upotrebom Mantel testa. Dobijeni rezultati analize oblika krila i genitalnog aparata mužjaka ukazuju na veliki potencijal geometrijske morfometrije u detekovanju morfolo&scaron;ke&nbsp; varijabilnosti, odnosno kriptičnih vrsta kod sirfida. Na osnovu oblika krila i genitalnog aparata mužjaka, unutar svih istraţivanih grupa vrsta prepoznato je 45 nezavisnih evolucionih jedinica (<em>M.</em>&nbsp;<em>aureus</em>&nbsp;grupa - 36;&nbsp; <em>M.</em> <em>nanus</em>&nbsp;grupa - 5,&nbsp; <em>M. avidus&nbsp;</em> kompleks&nbsp; -&nbsp; 4). Sve kriptične vrste iz 12 analiziranih kompleksa vrsta su uspe&scaron;no razdvojene, sa visokim procentom korektne klasifikacije jedinki. Rezultati ukazuju na veću moć diskriminacije oblika genitalnog aparata mužjaka u odnosu na krila. Razlike u obliku krila se odnose prvenstveno na promene u apikalnom delu<br />krila &scaron;to utiče na promene u dužini i &scaron;irini ovog dela, dok su razlike u obliku genitalnog aparata mužjaka najvećim delom koncentrisane u posteriornom delu posteriornog lobusa surstila, delu genitalnog aparata mužjaka koja igra ključnu ulogu u pridržavanju ženki tokom kopulacije. Razlike u obliku krila nisu posledica geografske udaljenosti, kao ni razlika u ekolo&scaron;kim ni&scaron;ama vrsta. Uticaj abiotičkih parametara na razlike u obliku genitalnog aparata mužjaka nije zabeležen ni kod jedne od analiziranih vrsta, dok je uticaj geografske distribucije na razlike u obliku surstila zabeležen samo u jednom slučaju, kod&nbsp; <em>M. luteomaculatus</em>&nbsp;kompleksa vrsta. Ovi rezultati ukazuju da je<br />izolacija putem distance imala glavnu&nbsp; ulogu u diverzifikaciji oblika genitalnog aparata mužjaka kod vrsta ovog kompleksa.</p><p>Rezultati su pokazali da se klimatski profili svih analiziranih parova vrsta razlikuju u makar jednoj sredinskoj ni&scaron;i (PC osi), osim para vrsta&nbsp; <em>M. rojoi - M. puniceus&nbsp;</em> i&nbsp; <em>M.&nbsp; loewi&nbsp; -&nbsp; M. ovaloides</em>. Faktori koji najvi&scaron;e doprinose&nbsp;divergenciji klimatskih profila analiziranih vrsta predstavljaju esktreme tj. limitirajuće faktore poput niskih vrednosti padavina i temperature i fluktuacija temperaure tokom godine. Za razliku od &scaron;iroko rasprostranjenih vrsta, endemske vrste imaju uzak opseg nadmorskih visina na kojima se javljaju i uglavnom su vezane za planinska stani&scaron;ta. Takođe, imaju niske vrednosti standardne devijacije za većinu izdvojenih PC osa &scaron;to ukazuje na njihovu striktnu klimatsku adaptibilnost. Prema rezultatima analize distribucije i specijskog diverziteta, Balkansko poluostrvo odlikuje najveći&nbsp;divezitet analiziranih vrsta. On predstavlja centar biodiverziteta za&nbsp;<em>M. aureus</em> grupu, a zajedno sa severnim delom Apeninskog poluostrva za <em>M. ruficornis</em> grupu, dok je najveći diverzitet vrsta <em>M. nanus</em>&nbsp;grupe zabeležen na jugozapadu i severoistoku Anadolije. Analize klimatskih profila i specijskog diverziteta zajedno sa rezultatima geometrijske morfometrije ukazuju da je geolo&scaron;ka istorija, tj. kontrakcije areala tokom glacijacija i interglacijacija, značajno uticala na diverzifikaciju istraživanih grupa u refugijumima zapadnog Palearktika.</p> / <p>The objects of this study are species from <em>Merodon aureus</em>, <em>M. nanus</em>&nbsp;and <em>M.&nbsp; ruficornis</em> groups, and <em>M. avidus</em> complex in Palaearctic. These species are characterised by great morphological&nbsp; similarity, and three different approaches were used to detect cryptic species and establish species boundaries. Species from <em>M. aureus</em>&nbsp;and <em>M.&nbsp; nanus</em>&nbsp;groups, and <em>M. avidus</em> complex were analysed using geometric morphometry. Interspecific variability of <em>M. aureus</em> group and <em>M. avidus</em> complex were studied using two approaches: landmark based wing shape analysis and semilandmark analysis of male genitalia.&nbsp; Ecological niche analysis were conducted for all analyzed species.&nbsp; Correlation between Squared Mahalanobis&nbsp; distances of both wing and surstylus, and geographic and environmental distances were addressed using&nbsp; the two tailed Mantel test. Geometric morphometric results indicate that wing and especially surstylus shape, have meaningful interspecific discriminatory power. Based&nbsp; on these characters 45 evolutionary independent units are recognized (<em>M. aureus</em>&nbsp;group - 36; <em>M. nanus</em>&nbsp;group - 5, <em>M. avidus</em> complex - 4). All cryptic species from 12 analysed species complexes were successfully distinguished with high overall&nbsp; classification success. Results showed that geometric morphometry of surstylus had a higher classification rate than wing geometric morphometry. The main wing shape differences are connected with apical part of the wing which influences his length and width. The main differences in surstylus shape are connected to the posterior margin of the posterior part of the surstylus lobe, involved in gripping the female during copulation. Mantel tests revealed that geographic and environmental distances exhibited no association with wing and&nbsp; surstylus shape distance among investigated species, except in <em>M. luteomaculatus</em>&nbsp; complex. In this complex, Mantel test results suggested that isolation by distance had a major role in the diversification of male genitalia.</p><p>Ecological niche analysis contributed to the species delimitation. These results demonstrated that among all related species, with the exception of species pairs <em>M. rojoi - M. puniceus</em> and <em>M. loewi - M. ovaloides</em>, overall or partial divergence in environmental&nbsp; space is present. Distribution patterns of all analyzed species are mainly affected by the limiting effects such as low temperature and precipitation values,&nbsp; as well as the temperature fluctuation during the year.</p><p>Endemics and species with a narrow range had smaller altitudinal ranges and were mainly connected with mountainous areas. Additionally, low standard deviation values for endemic species reflect their narrow geographic distribution and very strict climatic adaptations, whereas large values for widely distributed species reflect their broad adaptability.</p><p>According to the results of distribution and species diversity analysis, the Balkan Peninsula is characterized with highest diversity. It is a centre of biodiversity for&nbsp;<em>M. aureus</em> group, together with the northern part of the Apennine peninsula for <em>M. ruficorn</em>&nbsp;is group, while the largest species diversity of <em>M. nanus</em>&nbsp;group is recorded in the southwest and northeast Anadolia.</p><p>Distribution and species diversity analyses, together with&nbsp; the results of geometric morphometry indicate that geological history, i.e. range contraction during glaciations and interglaciations had a significant impact on the diversification of the studied groups in refuges in the Western Palaearctic.</p>
12

Revizija roda Eumerus Meigen, 1822 (Diptera: Syrphidae) na Balkanskom poluostrvu / Revision of the genus Eumerus Meigen, 1822 (Diptera: Syrphidae) on Balkan peninsula

Grković (Stefanović) Ana 27 August 2018 (has links)
<p>Osolike muve predstavljaju veliku familiju dvokrilaca koja u ekosistemu ima važnu ulogu opra&scaron;ivača biljaka i razlaganja organske materije. One su takođe dobar indikator naru&scaron;enosti ekosistema.&nbsp; Stoga je poznavanje njihove taksonomije i<br />ekologije od izuzetnog značaja. Jedan od tri najbrojnija roda osolikih muva&nbsp; predstavlja rod <em>Eumerus</em>, čija revizija na Balkanskom poluostrvu je predmet ove disertacije. Balkansko poluostrvo predstavlja izuzetan centar raznovrsnosti živog<br />sveta, između ostalih familija i za osolike muve. Za rod<em> Eumerus</em>, ono je pored Srednje Azije i Južne Afrike, jedan od centara specijacije.Predstavnici roda Eumerus su uglavnom sitnije crne muve, ponekad sa crvenim trbuhom. Karakteri&scaron;u ih bele popra&scaron;ene&nbsp; trake na tergitima, dva reda trnova na metafemuru&nbsp; apikoventralno i uvučena gornja spolja&scaron;nja poprečna vena na&nbsp; krilu, često sa dva kratka ispusta na ispupčenoj strani, okrenuta ka spolja. Cilj ove disertacije bio je utvrđivanje tačnog broja&nbsp; vrsta na Balkanskom poluostrvu i razre&scaron;avanje njihove&nbsp; taksonomije. Kao rezultat, utvrđeno je 44 prisutne vrste na&nbsp; istraživanom području koje su na osnovu morfolo&scaron;ke sličnosti&nbsp; podeljene u deset grupa. Tri utvrđene vrste ne pripadaju&nbsp; nijednoj grupi. U toku ovog istraživanja otkriveno je 12 vrsta novih za nauku:<em> E. aurofinis, E. banaticus</em>, in litt., <em>E. <span id="cke_bm_182S" style="display: none;">&nbsp;</span><span id="cke_bm_185S" style="display: none;">&nbsp;</span>bicornis</em><span id="cke_bm_185E" style="display: none;">&nbsp;</span><span id="cke_bm_182E" style="display: none;">&nbsp;</span>, in<span id="cke_bm_183S" style="display: none;">&nbsp;</span> litt., <span id="cke_bm_186S" style="display: none;">&nbsp;</span><em>E. crassus</em><span id="cke_bm_186E" style="display: none;">&nbsp;</span>, <span id="cke_bm_187S" style="display: none;">&nbsp;</span><em>E. kar<span id="cke_bm_183E" style="display: none;">&nbsp;</span>yates</em><span id="cke_bm_187E" style="display: none;">&nbsp;</span>, in li<span id="cke_bm_188S" style="display: none;">&nbsp;</span>tt., <em>E. montanum</em>, <em>E.&nbsp;<span id="cke_bm_188E" style="display: none;">&nbsp;</span> montenegr<span id="cke_bm_184E" style="display: none;">&nbsp;</span>inus, E. <span id="cke_bm_189E" style="display: none;">&nbsp;</span>nigrorufus</em>, in litt.<em>, E. phaeacus</em>, in litt., <span id="cke_bm_202S" style="display: none;">&nbsp;</span><em>E. rubrum, E. tenuitarsis</em><span id="cke_bm_202E" style="display: none;">&nbsp;</span>, in litt. i<em> E. torsicus.</em> Geometrijska morfometrija krila je d<span id="cke_bm_203E" style="display: none;">&nbsp;</span>ala odlične rezultate za razdvajanje&nbsp; kriptičnih taksona u okviru roda <em>Eumerus,</em> primenjena na&nbsp; vrstama grupe minotaurus. Utvrđeni su najznačajniji morfolo&scaron;ki karakteri za razlikovanje vrsta. Jedan od veoma&nbsp; značajnih rezultata ove disertacije je ključ za identifikaciju&nbsp; vrsta roda<em> Eumerus</em> na Balkanskom poluostrvu. Na osnovu morfolo&scaron;ke analize donet je zaključak da tricolor grupa&nbsp; predstavlja morfolo&scaron;ki zasebnu taksonomsku celinu sa jasnim&nbsp; indicijama da je njen rang iznad grupe vrsta. Centre diverziteta&nbsp; vrsta roda <em>Eumerus</em> na istraživanom području predstavljaju, prema bogastvu vrsta grčka ostrva Lezbos i Krf i jugoistočni&nbsp; deo Crne Gore uključujući Skadarsko jezero. Na osnovu &Scaron;enonovog indeksa diverziteta, područja sa najvećim indeksom su sledeća: ostrva Hios, Lezbos i Krf, zatim Peloponez i veći&nbsp; deo Crne Gore.</p> / <p>Hoverflies represents a large family of Diptera that have in the ecosystem an important role of pollinators and decomposer of organic matter. They are also a good indicator of ecosystem disruption. Therefore, knowledge of their taxonomy and ecology is of great importance. One of the three most numerous genus of hoverflies is the genus<em> Eumerus</em>, whose revision in the Balkan Peninsula is the subject of this dissertation. The Balkan Peninsula is an exceptional center of biodiversity, for&nbsp; hoverflies among other families. For the genus&nbsp;<em> Eumerus</em>, Balkan Peninsula is next to&nbsp; Central Asia and South Africa, one of the centers of speciation. Representatives of the genus&nbsp; Eumerus&nbsp; are mostly small black flies, sometimes with red abdomen. They are characterized by white stripes on the tergites, two rows of spines on the metafemur apico-ventrally and recessed upper outer transverse wing vein. The aim of&nbsp; this dissertation was to determine the number of species on the Balkan&nbsp; Peninsula and to resolve their taxonomy. As a result, 44 species were identified in the investigated area, which are divided into ten groups based on the&nbsp; morphological similarity. The three species identified do not belong to any group. In the course of this study, 12 new species were discovered for the science:&nbsp; <em>E. aurofinis, E. banaticus,</em> in litt.,&nbsp; <em>E. bicornis</em>, in litt.,&nbsp;<em> E. crassus,&nbsp; E. karyates</em>, in litt.,&nbsp; <em>E. montanum,&nbsp; E. montenegrinus,&nbsp; E. nigrorufus,</em> in litt.,&nbsp; <em>E. phaeacus</em>, in litt.,&nbsp; <em>E. rubrum,</em> <em>E. tenuitarsis</em>, in litt. and&nbsp; <em>E. torsicus</em>. The geometric&nbsp; morphometry of the wings gave excellent results for the separation of cryptic taxons within the genus&nbsp; Eumerus, applied to the species of the&nbsp; minotaurus&nbsp; group. The most important morphological characters for differentiating species were determined. One of the very important results of this dissertation is the identification key for species of the genus&nbsp; <em>Eumerus&nbsp;</em> on the Balkan Peninsula. Based on morphological analysis, conclusion is that the tricolor&nbsp; group represents a morphologically separate taxonomic entity with clear indications that its rank is above a group of species. The centers of diversity of the genus&nbsp;<em> Eumerus</em>&nbsp; in the research area represent, according to the species richness of the Greek island of Lesbos and Corfu and the southeastern&nbsp; part of Montenegro including the Skadar Lake. Based on the Shannon&rsquo;s Diversity Index, the areas with the highest index are as follows: the islands of Hios, Lesbos and Corfu, then Peloponnese and most of Montenegro.</p>

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