999 resultados para CRYPTIC DIVERSITY


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Protospathidium serpens (Kahl, 1930) is frequent in semiterrestrial and terrestrial habitats worldwide. Conventionally, all populations are considered as conspecific because they have very similar overall morphologies and morphometrics. We studied in detail not only the morphology of the vegetative cells but also the resting cysts using live observation, protargol impregnation, and scanning electron microscopy. These revealed a cryptic diversity and biogeographic pattern in details of the dorsal brush and cyst wall morphology. The cyst wall is spiny in the Austrian specimens, while smooth in the South African and Antarctic populations. Accordingly, P. serpens consists of at least two species: P. serpens (with spiny cyst wall) and P. fraterculum n. sp. (with smooth cyst wall); the latter is probably composed of two distinct taxa differing by the absence (South African)/presence (Antarctic) of a monokinetidal bristle tail in brush row 3, the number of dikinetids comprising brush row 1 (seven versus three), and the total number of brush dikinetids (29 versus 17). Protospathidium serpens is neotypitied with the new population from Austria. The significance of resting cyst morphology is discussed with respect to alpha-taxonomy and overall ciliate diversity.

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Despite the potential model role of the green algal genus Codium for studies of marine speciation and evolution, there have been difficulties with species delimitation and a molecular phylogenetic framework was lacking. In the present study, 74 evolutionarily significant units (ESUs) are delimited using 227 rbcL exon 1 sequences obtained from specimens collected throughout the genus' range. Several morpho-species were shown to be poorly defined, with some clearly in need of lumping and others containing pseudo-cryptic diversity. A phylogenetic hypothesis of 72 Codium ESUs is inferred from rbcL exon 1 and rps3-rp/16 sequence data using a conventional nucleotide substitution model (GTR + Gamma + I), a codon position model and a covariotide (covarion) model, and the fit of a multitude of substitution models and alignment partitioning strategies to the sequence data is reported. Molecular clock tree rooting was carried out because out-group rooting was probably affected by phylogenetic bias. Several aspects of the evolution of morphological features of Codium are discussed and the inferred phylogenetic hypothesis is used as a framework to study the biogeography of the genus, both at a global scale and within the Indian Ocean. (c) 2007 Elsevier Inc. All rights reserved.

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First described more that 150 years ago, the systematics of the genera Geomalacus and Letourneuxia (Arionidae, Gastropoda, Pulmonata) is still challenging. The taxonomic classification of arionid species is based on extremely labile characters such as body size or color that depends both on diet and environment, as well as age. Moreover, there is little information on the genetic diversity and population structure of the Iberian slugs that could provide extra clues to disentangle their problematic classification. The present work uses different analytical tools such as habitat suitability (Ecological Niche Modeling - ENM), cytogenetic analysis and phylogeography to establish the geographical distribution and evolutionary history of these pulmonate slugs. The potential distribution of the four Geomalacus species was modeled using ENM, which allowed the identification of new locations for G. malagensis, including a first report in Portugal. Also, it was predicted a much wider distribution for G. malagensis and G. oliveirae than previously known. Classical cytogenetic analyses were assayed with reproductive and a novel use of somatic tissues (mouth and tentacles) returning the number of chromosomes for the four Geomalacus species and L. numidica (n = 31, 2n = 62) and the respective karyotypes. G. malagensis and L. numidica present similar chromosome morphologies and karyotypic formulae, being more similar to each other than the Geomalacus among themselves. We further reconstructed the phylogeny of the genera Geomalacus and Letourneuxia using partial sequences of the mitochondrial cytochrome oxidase subunit I (COI) and the nuclear ribosomal small subunit (18S rRNA), and applied an independent evolutionary rate method, the indicator vectors correlation, to evaluate the existence of cryptic diversity within species. The five nominal species of Geomalacus and Letourneuxia comprise 14 well-supported cryptic lineages. Letourneuxia numidica was retrieved as a sister group of G. malagensis. G. oliveirae is paraphyletic with respect to G. anguiformis. According to our dating estimates, the most recent common ancestor of Geomalacus dates back to the Middle Miocene (end of the Serravallian stage). The major lineage splitting events within Geomalacus occurred during the dry periods of the Zanclean stage (5.3-3.6 million years) and some lineages were confined to more humid mountain areas of the Iberian Peninsula, which lead to a highly geographically structured mitochondrial genetic diversity. The major findings of this are the following: (1) provides updated species distribution maps for the Iberian Geomalacus expanding the known geographic distribution of the concerned species, (2) unravels the cryptic diversity within the genera Geomalacus and Letourneuxia, (3) Geomalacus oliveirae is paraphyletic with G. anguiformis and (4) Letourneuxia numidica is sister group of G. malagensis.

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Background: Symbiotic relationships have contributed to major evolutionary innovations, the maintenance of fundamental ecosystem functions, and the generation and maintenance of biodiversity. However, the exact nature of host/symbiont associations, which has important consequences for their dynamics, is often poorly known due to limited understanding of symbiont taxonomy and species diversity. Among classical symbioses, figs and their pollinating wasps constitute a highly diverse keystone resource in tropical forest and savannah environments. Historically, they were considered to exemplify extreme reciprocal partner specificity (one-to-one host-symbiont species relationships), but recent work has revealed several more complex cases. However, there is a striking lack of studies with the specific aims of assessing symbiont diversity and how this varies across the geographic range of the host. Results: Here, we use molecular methods to investigate cryptic diversity in the pollinating wasps of a widespread Australian fig species. Standard barcoding genes and methods were not conclusive, but incorporation of phylogenetic analyses and a recently developed nuclear barcoding gene (ITS2), gave strong support for five pollinator species. Each pollinator species was most common in a different geographic region, emphasising the importance of wide geographic sampling to uncover diversity, and the scope for divergence in coevolutionary trajectories across the host plant range. In addition, most regions had multiple coexisting pollinators, raising the question of how they coexist in apparently similar or identical resource niches. Conclusion: Our study offers a striking example of extreme deviation from reciprocal partner specificity over the full geographical range of a fig-wasp system. It also suggests that superficially identical species may be able to co-exist in a mutualistic setting albeit at different frequencies in relation to their fig host’s range. We show that comprehensive sampling and molecular taxonomic techniques may be required to uncover the true structure of cryptic biodiversity underpinning intimate ecological interactions.

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Molecular genetic date was used to test the taxonomic hypothesis of a single species of the freshwater shrimp, Paratya australiensis. While the results identified significant cryptic diversity, clear species boundaries could not be defined. The results of this study defy a simple taxonomic conclusion but are suggestive of incipient speciation.

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Capreolia is a monospecific genus of gelidioid red algae and has been considered to be endemic to Australasia. This is the first report on the occurrence of Capreolia implexa outside of Australasian waters, based on investigations of fresh collections in southern Chile as well as Australia and New Zealand. Thalli are prostrate and form entangled turfs, growing on high intertidal rocks at three locations in Chile. Analyses of rbcL and cox1 revealed that C. implexa was of Australasian origin and also distinct from its relatives. Analyses of 1356. bp of cox1 revealed cryptic diversity, consisting of two genealogical groups within C. implexa; one present in Australia and New Zealand, and the other in Chile and Stewart Island, New Zealand. The extremely low genetic diversity found in C. implexa in Chile and the absence of shared haplotypes between Chile and Australasia suggest genetic bottleneck possibly as a result of colonization after dispersal by rafting from Stewart Island, New Zealand to Chile. © 2014 Elsevier B.V.

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© 2015 The Linnean Society of London. Although important advances have been made in recent years in the taxonomy of different families and subfamilies of Malagasy bats, those belonging to the Vespertilioninae remain partially unresolved. Herein using a mitochondrial marker (cytochrome b) as the point of departure for 76 specimens of Malagasy vespers and appropriate African taxa, we diagnose the six taxa of this subfamily on the island by overlaying different morphological and bioacoustic characters on the clade structure of sequenced animals. The species include: endemic Neoromicia matroka, which is sister to African N. capensis; endemics N. malagasyensis and N. robertsi, which form sister species; a member of the genus Hypsugo, which is sister to African H. anchietae and described herein as new to science; Pipistrellus hesperidus for which Madagascar animals are genetically close but distinct from African populations of the same species; and endemic P. raceyi, which shows segregation of eastern (mesic) and western (dry) populations and its sister species relationships are unresolved. While the external and craniodental measurements, as well as bioacoustic variables, allow only partial differentiation of these six species of Vespertilioninae, molecular characters provide definitive separation of the taxa, as do male bacular morphology.

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As serpentes atuais são tradicionalmente divididas em dois grupos: Alethinophidia, taxonômica e ecologicamente mais diverso e Scolecophidia, grupo de serpentes fossoriais popularmente conhecidas como cobras-cegas, sendo Typhlopidae a família que possui maior número de espécies. Em função do hábito fossorial, os Typhlopidae são pouco representados em coleções cientificas e a escassez de amostras de tecido tem sido um fator limitante para realização de estudos moleculares dessa família. Por isso aspectos da biologia evolutiva como modos de especiação, padrão de diversificação e estruturação geográfica que devido o hábito fossorial e a pouca diferenciação morfológica intra e interespecífica são ainda pouco entendidos. Esse trabalho teve como objetivo analisar a variação morfológica e molecular de Typhlops reticulatus. Para isso foram analisados 314 exemplares de Typhlops, sendo 192 de T. reticulatus. Para análise morfológica foram utilizados caracteres morfométricos, morfológicos (folidose, hemipênis e osteologia craniana). Nas análises moleculares foram sequenciados 21 amostras de T. reticulatus dos genes mitocondriais Coi e Cyt b de diferentes localidades. As árvores filogenéticas foram feitas usando os métodos de Máxima Parcimônia e Máxima Verossimilhança e as relações entre os grupos foram inferidos através de rede de haplótipos. Através da combinação de caracteres moleculares e morfológicos foi possível observar a presença de duas linhagens evolutivas distintas de T. reticulatus: uma ao norte do Rio Amazonas e outra ao sul, esta última descrita como nova espécie nesse trabalho. Durante a análise dos exemplares de Typhlops para esse trabalho foi possível identificar duas novas espécies: Typhlops sp nov. 1 presente no Estado do Maranhão e Typhlops sp nov. 2 proveniente de Manaus, Amazonas. Os resultados desse estudo corroboram a afirmação que espécies com ampla distribuição geográfica podem apresentar diversidade críptica considerável e uma história evolutiva mais complexa do que se imagina.

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This paper is part of an extensive study on the biodiversity of the macroalgal flora of So Paulo state, SE Brazil. Previous assessments were based only on morphological descriptions. Here, we tested the effectiveness of DNA barcoding, in comparison with morphological observations for the recognition and cataloging of species. The focus of this study is the genus Porphyra, which is a conspicuous component of the upper intertidal on rocky shores of this region. With five currently accepted species, we have sequenced three short markers: cox1, cox2-3 spacer and UPA to establish the first DNA barcode database for the Porphyra species from the Brazilian coast. The three markers, although with different evolution rates, recovered a cryptic species (Porphyra sp. 77), grouped two different species (Porphyra drewiana and Porphyra spiralis) that are being synonymized, and finally indicated that varieties within P. acanthophora and P. spiralis are merely morphological, with no sequence divergence in the studied molecular markers.

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Die Phylogenie der Westpaläarktischen Langohren (Mammalia, Chiroptera, Plecotus) – eine molekulare Analyse Die Langohren stellen eine Fledermausgattung dar, die fast alle westpaläarktischen Habitate bist zum Polarkreis hin besiedeln und in vielerlei Hinsicht rätselhaft sind. In der Vergangenheit wurden zahlreiche Formen und Varietäten beschrieben. Trotzdem galt für lange Zeit, dass nur zwei Arten in Europa anerkannt wurden. Weitere Arten waren aus Nordafrika, den Kanaren und Asien bekannt, aber auch deren Artstatus wurde vielfach in Frage gestellt. In der vorliegenden Dissertation habe ich mittels molekularer Daten,der partiellen Sequenzierung mitochondrialer Gene (16S rRNA und ND1), sowie der mitochondrialen Kontrollregion, eine molekular Analyse der phylogenetischen Verwandtschaftsverhältnisse innerhalb und zwischen den Linien der westpaläarktischen Langohren durchgeführt. Die besten Substitutionsmodelle wurden berechnet und phylogenetische Bäume mit Hilfe vier verschiedener Methoden konstruiert: dem neighbor joining Verfahren (NJ), dem maximum likelihood Verfahren (ML), dem maximum parsimony Verfahren (MP) und dem Bayesian Verfahren. Sechs Linien der Langohren sind genetisch auf einem Artniveau differenziert: Plecotus auritus, P. austriacus, P. balensis, P. christii, P. sardus, und P. macrobullaris. Im Falle der Arten P. teneriffae, P. kolombatovici und P. begognae ist die alleinige Interpretation der genetischen Daten einzelner mitochondrialer Gene für eine Festlegung des taxonomischen Ranges nicht ausreichend. Ich beschreibe in dieser Dissertation drei neue Taxa: Plecotus sardus, P. kolombatovici gaisleri (=Plecotus teneriffae gaisleri, Benda et al. 2004) and P. macrobullaris alpinus [=Plecotus alpinus, Kiefer & Veith 2002). Morphologische Kennzeichen, insbesondere für die Erkennung im Feld, werden hier dargestellt. Drei der sieben Arten sind polytypisch: P. auritus (eine west- und ein osteuropäische Linie, eine sardische Linie und eine aktuell entdeckte kaukasische Linie, Plecotus kolombatovici (P. k. kolombatovici, P. k. gaisleri und P. k. ssp.) und P. macrobullaris (P. m. macrobullaris und P. m. alpinus). Die Verbreitungsgebiete der meisten Arten werden in dieser Arbeit erstmals ausschließlich anhand genetisch zugeordneter Tiere dargestellt.Die Untersuchung der ökologischen Einnischung der nun anerkannten Formen, insbesondere in Gebieten sympatrischer Verbreitung, bietet ein spannendes und lohnendes Feld für zukünftige Forschungen. Nicht zuletzt muss sich die Entdeckung eines beachtlichen Anteils kryptischer Diversität innerhalb der westpaläarktischen Langohren auch bei der Entwicklung spezieller Artenschutzkonzepte widerspiegeln.

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The relationship and phylogeny of the western Palearctic harvestmen family Trogulidae is investigated. The traditional system of seven genera and approximately 40 species appeared to be artificially composed but a phylogenetic approach and a comprehensive revision has long been sought after. Species are poorly characterised due to their uniform morphology and species evaluation is furthermore complicated by the variability of the few characters used for species delineation. To meet these demands a molecular genetic analysis is accomplished using the nuclear 28S rRNA gene and the mitochondrial cytochrome b gene. This analysis incorporates most genera and species of Trogulidae as well as a comprehensive set of Nemastomatidae and Dicranolasmatidae as outgroup taxa. Phylogenetic results of Bayesian analysis, Maximum Parsimony, Maximum Likelihood and Neighbor Joining are compared with distributional data, morphological characters and results of canonical discriminant analysis of morphometric characters and general congruence of these data sets is shown. To demonstrate the applicability of this method the revision of two species-groups within Trogulus is set out in detail. The Trogulus hirtus species-group and the Trogulus coriziformis species-group are revised. The former is in the central and north-western Balkan Peninsula. T. tricarinatus ssp. hirtus is raised to species level and four new species are described (T. karamanorum [man.n.], T. melitensis [man.n.], T. pharensis [man.n]; T. thaleri [man.n.]). The Trogulus coriziformis species-group is confined to the western Mediterranean area. T. coriziformis, T. aquaticus are re-described, T. cristatus and T. lusitanicus are re-established and four species are described as new (T. balearicus, T. huberi, T. prietoi, T. pyrenaicus). In both species-groups two further cryptic species probably exist but were not described. The species groups are shown to represent different phylogenetic levels and this information is used for the revisional work on the genus Trogulus as well as for the generic system of Trogulidae. Family status of Dicranolasmatidae is rejected and Dicranolasma is shown to be best incorporated within Trogulidae. Calathocratus, Platybessobius and Trogulocratus appear to be polyphyletic and are best to be united within Calathocratus, the oldest name of this set. The cryptic diversity within Trogulidae, especially in Trogulus and the composed genus Calathocratus rates to 150-235% and is thereby remarkably high for a group of the generally well researched European fauna. Genetic features of the group such as heteroplasmy, the possibility of major gene rearrangements and usability of the cytochrome b gene for phylogenetic studies in Opiliones are outlined.

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Alle Doldengewächse (Apiaceae), darunter die größte, weltweit verbreitete Unterfamilie der Apioideen, weisen in ihren Blütenständen sehr einheitliche Merkmale auf. Die ‚Doppeldolden´ werden aus kleinen, weißen oder gelben Blüten gebildet und von vielen unspezialisierten Insekten besucht. Der uniforme Eindruck, der damit erweckt wird, ist unter Umständen ein Grund, dass die zugrundeliegende Morphologie bislang wenig untersucht wurde. Gegenstand der vorliegenden Dissertation ist es daher, die ‚verborgene Diversität´ im Blütenstandsbereich der Apiaceae -Apioideen mit dem Ziel darzustellen, den Einfluss der Architektur der Pflanzen auf die Art der Blütenpräsentation in Raum und Zeit und damit auf das Reproduktionssystem der Art zu ermitteln. Im ersten Kapitel zeigt der Vergleich von neun ausgewählten Arten, dass in den selbstfertilen und unspezifisch bestäubten Pflanzen durch Synchronisation und Rhythmik in der Präsentation von Blüten Fremdbefruchtung gefördert wird. Entweder durchlaufen die Pflanzen dabei nur eine getrennte männliche und weibliche Blühphase (Xanthoselinum alsaticum) oder der moduläre Bau der Pflanzen führt zu einer Folge männlicher und weiblicher Blühphasen (multizyklische Dichogamie). Die Diözie in Trinia glauca kann in diesem Zusammenhang als eine Trennung der Blühphasen auf verschiedengeschlechtliche Individuen gesehen werden. Für die andromonözischen Arten wird gezeigt, dass der Anteil funktional männlicher Blüten mit steigender Doldenordnung nicht einheitlich zu- oder abnimmt. Dadurch fungieren die Pflanzen zu verschiedenen Zeiten und mit unterschiedlicher Stärke eher als Pollenrezeptoren oder Pollendonatoren. Es wird deutlich, dass das ‚uniforme Muster‘ der Apioideen mit Dolden verschiedener Ordnungen, dichogamen Blüten und deren diversen Geschlechtsausbildungen ein komplexes Raum-Zeit-Gefüge zur Optimierung des Reproduktionssystems darstellt. Das zweite Kapitel stellt die Ergebnisse von Manipulationsexperimenten (Handbestäubung, Bestäuberabschirmung, Entfernen von Dolden niedriger Ordnung) an Chaerophyllum bulbosum dar, die zeigen, dass das Raum-Zeit-Gefüge in der Präsentation der Blüten der Art erlaubt, flexibel auf Umwelteinflüsse zu reagieren. Es stellt sich heraus, dass mechanische Beschädigungen kaum Einfluss auf den Andromonöziegrad und prozentualen Fruchtansatz der Individuen nehmen. Grundvoraussetzung der Reaktionsfähigkeit ist wiederum deren modulärer Bau. Dieser erlaubt es den Pflanzen, zusammen mit dem andromonöziebedingten Reservoir an - geschlechtlich flexiblen - männlichen Blüten, in den später angelegten Dolden fehlenden Fruchtansatz der Blüten früh blühender Dolden zu kompensieren. Im dritten Kapitel wird eine vergleichende Merkmalsanalyse an 255 Apioideen-Arten vorgelegt, die alle Verwandtschaftskreise, Wuchsformen und Verbreitungsgebiete der Gruppe repräsentieren. Ziel der Analyse war die Identifizierung von Merkmalssyndromen, die den Zusammenhang zwischen Architektur und Reproduktionssystem verdeutlichen sollten. Interessanterweise sind die einzigen Merkmale, die miteinander einhergehen, Protogynie und die graduelle Abnahme männlicher Blüten mit steigender Doldenordnung. Alle anderen Merkmale variieren unabhängig voneinander und erzeugen auf vielen verschiedenen Wegen immer wieder das gleiche Funktionsmuster, das als ‚breeding syndrome‘ der Apioideae gedeutet werden kann. Die Arbeit leistet einen wichtigen Beitrag zum Verständnis der Blütenstände der Apiaceen und darüber hinaus zu morphologischer Variation in ‚unspezialisierten‘ Reproduktionssystemen. Offensichtlich liegt in den Apioideen der Selektionsdruck auf der Aufrechterhaltung der generalisistischen Bestäubung und überprägt alle morphologisch-phylogenetischen Merkmalsvarianten.

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The accurate reconstruction of sea surface temperature (SST) history in climate-sensitive regions (e.g. tropical and polar oceans) became a challenging task in palaeoceanographic research. Biogenic shell carbonate SST proxies successfully developed for tropical regions often fail in cool water environments. Their major regional shortcomings and the cryptic diversity now found within the major high latitude proxy carrier Neogloboquadrina pachyderma (sin.) highlight an urgent need to explore complementary SST proxies for these cool-water regions. Here we incorporate the genetic component into a calibration study of a new SST proxy for the high latitudes. We found that the calcium isotopic composition (δ44/40Ca) of calcite from genotyped net catches and core-top samples of the planktonic foraminifera Neogloboquadrina pachyderma (sin.) is related to temperature and unaffected by genetic variations. The temperature sensitivity has been found to be 0.17 (±0.02)‰ per 1°C, highlighting its potential for downcore applications in open marine cool-water environments. Our results further indicate that in extreme polar environments, below a critical threshold temperature of 2.0 (±0.5)°C associated with salinities below 33.0 (±0.5)‰, a prominent shift in biomineralization affects the δ44/40Ca of genotyped and core-top N. pachyderma (sin.), becoming insensitive to temperature. These findings highlight the need of more systematic calibration studies on single planktonic foraminiferal species in order to unravel species-specific factors influencing the temperature sensitivity of Ca isotope fractionation and to validate the proxies' applicability.

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The Sonne transit cruise SO226-3 DipFIP took place from March 4th (Wellington, New Zealand) to March 28th (Kaohsiung, Taiwan) in 2013. CTD data for 16 stations along the cruise track were recorded using the onboard a SEABIRD SBE 9 plus CTD down to depth of 800m. Obtained hydrographic data were binned to 1 m intervals with the available SBE software. Obvious outliers in the readings of the oxygen sensor close to the sea surface have been manually removed. Fluorospectrometer (bbe Moldaenke) pigment data measured for 24 depth intervals are available for 10 stations. Measurements were conducted in the shipboard laboratory on water samples from the CTD rosette. Data are averages of a least 30 readings per sample.