| 1. |
- Anderberg, Arne A., et al.
(författare)
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Evolutionary relationships in the Asteraceae tribe Inuleae (incl. Plucheeae) evidenced by DNA sequences of ndhF; with notes on the systematic positions of some aberrant genera
- 2005
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Ingår i: Organisms Diversity & Evolution. - : Elsevier BV. - 1439-6092 .- 1618-1077. ; 5:2, s. 135-146
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Tidskriftsartikel (refereegranskat)abstract
- The phylogenetic relationships between the tribes Inuleae sensu stricto and Plucheeae are investigated by analysis of sequence data from the cpDNA gene ndhF. The delimitation between the two tribes is elucidated, and the systematic positions of a number of genera associated with these groups, i.e. genera with either aberrant morphological characters or a debated systematic position, are clarified. Together, the Inuleae and Plucheeae form a monophyletic group in which the majority of genera of Inuleae s.str. form one clade, and all the taxa from the Plucheeae together with the genera Antiphiona, Calostephane, Geigeria, Ondetia, Pechuel-loeschea, Pegolettia, and Iphionopsis from Inuleae s.str. form another. Members of the Plucheeae are nested with genera of the Inuleae s.str., and support for the Plucheeae clade is weak. Consequently, the latter cannot be maintained and the two groups are treated as one tribe, Inuleae, with the two subtribes Inulinae and Plucheinae. The genera Asteriscus, Chrysophthalmum, Inula, Laggera, Pentanema, Pluchea, and Pulicaria are demonstrated to be non-monophyletic. Cratystylis and Iphionopsis are found to belong to the same clade as the taxa of the former Plucheeae. Caesulia is shown to be a close relative of Duhaldea and Blumea of the Inuleae-Inulinae. The genera Callilepis and Zoutpansbergia belong to the major clade of the family that includes the tribes Heliantheae sensu lato and Inuleae (incl. Plucheeae), but their exact position remains unresolved. The genus Gymnarrhena is not part of the Inuleae, but is either part of the unresolved basal complex of the paraphyletic Cichorioideae, or sister to the entire Asteroideae.
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| 2. |
- Chiocchio, Andrea, et al.
(författare)
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Unveiling cryptic diversity among Müllerian co-mimics : insights from the Western Palaearctic Syntomis moths (Lepidoptera: Erebidae: Arctiinae)
- 2021
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Ingår i: Organisms Diversity and Evolution. - : Springer Science and Business Media LLC. - 1439-6092 .- 1618-1077. ; 21:1, s. 119-133
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Tidskriftsartikel (refereegranskat)abstract
- Accurate species delimitation is of primary importance in biodiversity assessments and in reconstructing patterns and processes in the diversification of life. However, the discovery of cryptic species in virtually all taxonomic groups unveiled significant gaps in our knowledge of biodiversity. Mimicry complexes are good candidates to source for cryptic species. Indeed, members of mimicry complexes undergo selective pressures on their habitus, which results in strong resemblance even between distantly related species. In this study, we used a multi-locus genetic approach to investigate the presence of cryptic diversity within a group of mimetic day-flying moths whose systematics has long been controversial, the Euro-Anatolian Syntomis. Results showed incongruence between species boundaries and the currently accepted taxonomy of this group. Both mitochondrial and nuclear markers indicate the presence of four, well-distinct genetic lineages. The genetic distance and time of divergence between the Balkan and Italian populations of S. marjana are the same as those found between S. phegea and S. ragazzii, the last two being well-distinct, broadly sympatrically occurring species. The divergence between the two lineages of S. marjana dates back to the Early Pleistocene, which coincided with substantial changes in climatic conditions and vegetation cover in Southern Europe that have likely induced geographic and ecological vicariance. Syntomis populations belonging to the taxa kruegeri (s. str.), albionica and quercii are now considered a separate species from marjana s. str. and are thus distinguished as Syntomis quercii Verity, 1914, bona sp., stat. nov. Our results show that the species richness of mimicry complexes inhabiting temperate regions might still be severely underestimated.
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| 3. |
- Erséus, Christer, 1951, et al.
(författare)
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The popular model annelid Enchytraeus albidus is only one species in a complex of seashore White Worms (Clitellata, Enchytraeidae)
- 2019
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Ingår i: Organisms Diversity & Evolution. - : Springer Science and Business Media LLC. - 1439-6092 .- 1618-1077. ; 19:2, s. 105-133
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Tidskriftsartikel (refereegranskat)abstract
- The white worm Enchytraeus albidus Henle, 1837 (Clitellata, Enchytraeidae) is easy to keep in laboratory cultures, and has therefore been employed as a model organism in basic and applied biological research. Its natural habitat includes terrestrial composts and wrack beds on seashores. However, the name E. albidus is currently used for a complex of morphologically similar and closely related species. We here revise the components of the E. albidus species complex based on a sample of 100 Enchytraeus specimens from 56 sites, most of which are across Europe. These samples were DNA-barcoded for the mitochon- drial COI gene. A subset of them was sequenced for the nuclear ITS2 and H3 markers. Six species were delimited with strong support by the COI and ITS2 gene trees, as well as by a multi-locus species delimitation analysis. These species are identified morphologically and described as E. albidus s. str. (with designation of a neotype); Enchytraeus moebii (Michaelsen, 1885); Enchytraeus albellus Klinth, Erséus and Rota, sp. nov., E. cf. krumbachi (Čejka, 1913), E. sp. 1 (unnamed), and Enchytraeus polatdemiri Arslan and Timm, 2018. The last-mentioned species is a soda lake specialist, whereas E. albidus s. str. is both terrestrial and marine littoral; all other species occur only in seashores. The phylogeny of this group was estimated using the multi-species coalescent model. Monophyly of the E. albidus complex was recovered. Within this complex, three groups were recovered as monophyletic, but the relationship between them is unclear. One group comprises E. albidus s. str., E. albellus, and E. moebii; the second group E. cf. krumbachi and the unnamed E. sp. 1, and the third consists of only E. polatdemiri. This study serves as a framework for genetic identification of white worms used for experimental purposes.
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| 4. |
- Guggolz, Theresa, et al.
(författare)
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High diversity and pan-oceanic distribution of deep-sea polychaetes: Prionospio and Aurospio (Annelida: Spionidae) in the Atlantic and Pacific Ocean
- 2020
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Ingår i: Organisms Diversity & Evolution. - : Springer Science and Business Media LLC. - 1439-6092 .- 1618-1077.
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Tidskriftsartikel (refereegranskat)abstract
- Prionospio Malmgren 1867 and Aurospio Maciolek 1981 (Annelida: Spionidae) are polychaete genera commonly found in the deep sea. Both genera belong to the Prionospio complex, whose members are known to have limited distinguishing characters. Morphological identification of specimens from the deep sea is challenging, as fragmentation and other damages are common during sampling. These issues impede investigations into the distribution patterns of these genera in the deep sea. In this study, we employ two molecular markers (16S rRNA and 18S) to study the diversity and the distribution patterns of Prionospio and Aurospio from the tropical North Atlantic, the Puerto Rico Trench and the central Pacific. Based on different molecular analyses (Automated Barcode Gap Discovery, GMYC, pairwise genetic distances, phylogenetics, haplotype networks), we were able to identify and differentiate 21 lineages (three lineages composed solely of GenBank entries) that represent putative species. Seven of these lineages exhibited pan-oceanic distributions (occurring in the Atlantic as well as the Pacific) in some cases even sharing identical 16S rRNA haplotypes in both oceans. Even the lineages found to be restricted to one of the oceans were distributed over large regional scales as for example across the Mid-Atlantic Ridge from the Caribbean to the eastern Atlantic (> 3389 km). Our results suggest that members of Prionospio and Aurospio may have the potential to disperse across large geographic distances, largely unaffected by topographic barriers and possibly even between oceans. Their high dispersal capacities are probably explained by their free-swimming long-lived planktonic larvae.
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| 5. |
- Kånneby, Tobias, 1981-, et al.
(författare)
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The phylogenetic position of Neogosseidae (Gastrotricha: Chaetonotida) and the origin of planktonic Gastrotricha
- 2015
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Ingår i: Organisms Diversity & Evolution. - : Springer Berlin/Heidelberg. - 1439-6092 .- 1618-1077. ; 15:3, s. 459-469
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Tidskriftsartikel (refereegranskat)abstract
- Planktonic forms of Gastrotricha have been known since the 1850s, despite the fact that they are rather uncommon and difficult to collect. They are characterized by a round sack-shaped body, an absence of furcal adhesive tubes, and a different distribution of the locomotory ciliation compared to epibenthic and periphytic gastrotrichs. Today, planktonic gastrotrichs are classified into the three taxa—Dasydytidae, Neogosseidae, and Undula—but their origin and whether they share a recent common ancestor remain largely unknown. A long-held view is that planktonic taxa are derived from benthic ancestors related to Chaetonotus (Zonochaeta), but the hypothesis has never been properly tested. Here, in order to elucidate the phylogeny and origin of planktonic Gastrotricha, we provide the first molecular data on the very rare genera Kijanebalola and Neogossea, both members of the family Neogosseidae. We use Bayesian and maximum likelihood phylogenetics to analyze sequences of 18S rDNA, 28S rDNA, and COI mtDNA spanning 71 taxa in total. We find high support for a common origin of planktonic gastrotrichs, with monophyly of both Dasydytidae and Neogosseidae. Planktonic forms have evolved from epibenthic or periphytic ancestors, and the closest extant clade comprises members of Chaetonotus (Zonochaeta) + Chaetonotus heteracanthus Remane, 1927. These results further imply that the motile spines and underlying muscle patterns that control them in species of Dasydytidae are adaptations to the planktonic environment that evolved independently of those in other species of Gastrotricha.
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| 6. |
- Larsson, Karolina, et al.
(författare)
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DNA taxonomy of Swedish Catenulida (Platyhelminthes) and a phylogenetic framework for catenulid classification
- 2008
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Ingår i: Organisms Diversity & Evolution. - : Elsevier BV. - 1439-6092 .- 1618-1077. ; 8:5, s. 399-412
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Tidskriftsartikel (refereegranskat)abstract
- Specimens of Catenulida were collected at 34 localities in Sweden. We used 18S rDNA. 28S rDNA, ITS-5.8S. and cytochrome oxidase I (COI) nucleotide sequences to infer phylogeny from parsimony jackknifing and Bayesian analysis. Our dataset contained 74 ingroup terminals and 5111 characters. The results show it basal split between it clade consisting of the marine Retronectidae + the limnic Catenulidae. and it second clade consisting, of the limnic Stenostomidae. The hypothesis of the marine Retronectidae as the Sister group of the limnic Catenulida is rejected. The recently introduced genus Anokkostenostomum Norena, Damborenea & Brusa, 2005 results its non-monophyletic, and Suomina Marcus. 1945 its it group inside Catenula Duges, 1832. Therefore, we propose to render Anokkostenostomum a new junior synonym of Stenostomum Schmidt, 1848. and Suomina it new junior synonym of Catenula. Consequently, the new combinations Catenula evelinae (Marcus, 1945), Catenula sawayai (Marcus. 1945), and Catenula turgida (Zacharias. 1902) are proposed. and 14 species are returned to their original genus, Stenostomum. The molecular phylogenetic hypothesis is used to identify and discriminate catenulid species. In Our material. we found 12 species of Catenulida new to Sweden, and four Species new to science. all of which are distinguishable by morphological characters.
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| 7. |
- Larsson, Karolina, et al.
(författare)
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Phylogeny of Catenulida and support for Platyhelminthes
- 2008
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Ingår i: Organisms Diversity & Evolution. - : Elsevier BV. - 1439-6092 .- 1618-1077. ; 8:5, s. 378-387
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Tidskriftsartikel (refereegranskat)abstract
- Molecular studies have shown that Platyhelminthes is polyphyletic, placing Rhabditophora within Lophotrochozoa, whereas Acoela and Nemertodermatida are separate early bilaterian branches. However, there has been little evidence to support the position of Catenulida, a group that was traditionally classified within Platyhelminthes. In Ehlers' pioneering cladistic system of the Platyhelminthes they were placed as the earliest clade. Other morphologists have considered the Catenulida as an early bilaterian clade separate from Rhabditophora, a position that was supported in an early molecular study. Subsequent molecular phylogenetic studies, which placed Catenulida as the sister group of Rhabditophora with no or low branch support, included 18S rDNA data from only one or two catenulid species. The aims of the present study were (1) to test the putative sister-group relationship of Catenulida and Rhabditophora by improving the taxon sampling of molecular data spanning a larger part of catenulid taxonomic diversity and (2) to provide a phylogenetic framework for the systematization of Catenulida. Twelve catenulid species were sampled around Sweden. Both the 18S rDNA gene and the 28S rDNA gene were sequenced and analysed in a Metazoa-wide data set within parsimony and Bayesian frameworks. The results unambiguously support Catenulida as the sister group of Rhabditophora within Lophotrochozoa. Parsimony-based inferences about the common ancestor of Catenulida and Rhabditophora are presented. A definition of the name Platyhelminthes is suggested.
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| 8. |
- Liu, Yingkui, et al.
(författare)
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Extensive cryptic diversity in the cosmopolitan sludge worm Limnodrilus hoffmeisteri (Clitellata, Naididae)
- 2017
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Ingår i: Organisms Diversity and Evolution. - : Springer Science and Business Media LLC. - 1439-6092 .- 1618-1077. ; 17:2, s. 477-495
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Tidskriftsartikel (refereegranskat)abstract
- Limnodrilus hoffmeisteri Claparède, 1862 is a common freshwater worm, often regarded as an indicator of organic pollution. The taxonomic status of this species is controversial due to great variation in morphological features. Numerous morphological forms of L. hoffmeisteri are recorded in the literature, especially from Europe and North America. Today, DNA-based species delimitation assumes that species boundaries can be more objectively and effectively estimated using genetic data rather than with morphological data alone. To investigate if L. hoffmeisteri is a single species, 295 worms identified as either L. hoffmeisteri or other similar (congeneric) morphospecies, using currently accepted morphological criteria, were collected from 82 locations in the northern hemisphere. The number of primary species hypotheses (PSHs) was first explored with cytochrome oxidase subunit I (COI), the proposed DNA barcode for animal species, and with data for all specimens. Both automatic barcoding gap discovery (ABGD) and the Bayesian general mixed Yule coalescent (bGMYC) model revealed the existence of ≥25 distinct PSHs (COI lineages) in our dataset. Then, smaller samples of individuals representing major COI lineages were used for exploration of a nuclear locus, the internal transcribed spacer (ITS) region. In the ITS gene tree (81 sequences), generated by BEAST, 16 well-supported terminal groups were found, but not all of these groups were congruent with the PSHs found in the COI tree. As results across these different analyses were inconsistent, we resorted to analyzing reciprocal monophyly between gene trees and used a minimum consensus of all evidence, suggesting that there are 13 separately evolving lineages (=13 species) within our sample. The smallest uncorrected COI p-distance between these species is 12.1%, and the largest intraspecific p-distance is 16.4%, illustrating the problem of species delimitation with a DNA-barcoding gap as the sole criterion. Ten of these species are morphologically identified as “L. hoffmeisteri,” the remaining three can be attributed to morphologically distinct congeneric species. An individual from the type locality in Switzerland was designated as a neotype of L. hoffmeisteri sensu stricto. This worm belongs to one of the ten species, and this lineage is widely distributed in Europe, Asia, and North America. The remaining nine species show a mixed distribution pattern; some appear to be endemic to a restricted area, others are Holarctic. Our results provide clues to the future revalidation of some of the nominal species today placed in synonymy with L. hoffmeisteri. A BEAST analysis, based on previously published and newly generated 16S data, suggested that this complex contains also other species than those studied by us. By integrating additional genetic data, it will be possible to identify these and additional specimens in future studies of Limnodrilus, and the neotype provides a baseline for further revisions of the taxonomy of the L. hoffmeisteri complex.
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| 9. |
- Martin, D., et al.
(författare)
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The symbiotic hesionid Parasyllidea humesi Pettibone, 1961 (Annelida: Polychaeta) hosted by Scrobicularia plana (da Costa, 1778) (Mollusca: Bivalvia: Semelidade) in European waters
- 2012
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Ingår i: Organisms Diversity & Evolution. - : Springer Science and Business Media LLC. - 1439-6092 .- 1618-1077. ; 12:2, s. 145-153
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Tidskriftsartikel (refereegranskat)abstract
- Heretofore, the hesionid polychaete Parasyllidea humesi was only known from its original description, living in association with the bivalve Tellina nymphalis in mangrove swamps north of Pointe-Noire (Republic of Congo, West Africa). The discovery of a stable population in Rio San Pedro (Gulf of Cadiz, southern Atlantic coast of Iberian Peninsula) thus represents the second report for this species worldwide, and the first for European waters. Furthermore, the new population is associated with another bivalve, Scrobicularia plana. The host-symbiont relationship is characterized by a high host-specificity (the symbiont was absent from Ruditapes decussatus and Cerastoderma glaucum collected in the same habitat and location), regular distribution (one, exceptionally two symbionts per host and then being male and female), and prevalence ranging from 0.22 % (in Cao Sancti Petri) to 4.74 % (Rio San Pedro). The symbionts seem to affect the metabolism of their hosts and, thus, their normal growth, so this association may tentatively be considered as close to parasitism. Parasyllidea humesi seems to be restricted to salt marsh areas with stable marine salinities all over the year. As there is no evidence that the presence of P. humesi in the Gulf of Cadiz results from an introduction, we strongly suggest that it may be better considered as native to the region, with our finding representing the northernmost known geographical limit of its distribution.
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| 10. |
- Meyer-Wachsmuth, Inga, et al.
(författare)
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Interrelationships of Nemertodermatida
- 2016
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Ingår i: Organisms Diversity & Evolution. - : Springer Science and Business Media LLC. - 1439-6092 .- 1618-1077. ; 16:1, s. 73-84
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Tidskriftsartikel (refereegranskat)abstract
- Nemertodermatida is a small taxon of microscopic marine worms, which were originally classified within Platyhelminthes. Today they are hypothesized to be either an early bilaterian lineage or the sister group to Ambulacraria within Deuterostomia. These two hypotheses indicate widely diverging evolutionary histories in this largely neglected group. Here, we analyse the phylogeny of Nemertodermatida using nucleotide sequences from the ribosomal LSU and SSU genes and the protein coding Histone 3 gene. All currently known species except Ascoparia neglecta and Ascoparia secunda were included in the study in addition to several yet undescribed species. Ascopariidae and Nemertodermatidae are retrieved as separate clades, although not in all analyses as sister groups. Non-monophyly of Nemertodermatida was rejected by the Approximately Unbiased test. Nemertodermatid nucleotide sequences deposited in Genbank before 2013 were validated against our dataset; some of them are shown to be chimeric implying falsification of prior hypotheses about nemertodermatid phylogeny: other sequences should be assigned new names. We also show that the genus Nemertoderma needs revision.
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| 11. |
- Nygren, Arne, 1971, et al.
(författare)
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Cryptic species of Notophyllum (Polychaeta: Phyllodocidae) in Scandinavian waters
- 2010
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Ingår i: Organisms Diversity & Evolution. - : Springer Science and Business Media LLC. - 1439-6092 .- 1618-1077. ; 10:3, s. 193-204
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Tidskriftsartikel (refereegranskat)abstract
- The phyllodocid polychaete Notophyllum foliosum occurs in two colour morphs in Swedish and Norwegian waters, one palish yellow to grey form with black patches that is restricted to deeper waters and often associated with reefs of the deep-water coral Lophelia pertusa, and one usually yellow-orange form with black patches and white spots that is usually encountered on more shallow bottoms. We have sampled the two forms from sympatric occurrences in Norway, and the shallow form from the Swedish west coast. Phylogenetic and haplotype analyses based on the mitochondrial cytochrome c oxidase subunit I (COI) gene and the nuclear internal transcribed spacer region (ITS1-5.8SrDNA-ITS2) unequivocally indicate that the two forms represent different species. We apply the name N. foliosum (Sars, 1835) to the 'shallow form', and propose N. crypticum n. sp. for the 'deep form'. A lectotype is fixed for N. foliosum.
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| 12. |
- Obst, Matthias, 1974, et al.
(författare)
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A new species of Cycliophora from the mouthparts of the American lobster, Homarus americanus (Nephropidae, Decapoda)
- 2006
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Ingår i: Organisms Diversity and Evolution. - : Elsevier BV. - 1439-6092 .- 1618-1077. ; 6:2, s. 83-97
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Tidskriftsartikel (refereegranskat)abstract
- The present study describes a new species of Cycliophora with the aid of light- and electron microscopy. The animals live attached or free-living on the mouth appendages of the American lobster, Homarus americanus. Individuals occur in dense clusters of up to several thousand individuals. The new species is named Symbion americanus sp. nov. according to the name of its host; it can be distinguished from the previously described species Symbion pandora by the presence of a posterior pair of retractable tubular appendages or toes in the Prometheus larva. Morphological variation among cycliophorans on H. americanus collected in different localities seems to be high. In several sexual populations of S. americanus, older feeding individuals with a female typically have 5-13 rings of cuticular scars and a thicker cuticle. Moreover, attached Prometheus larvae frequently contain three males, chordoid cysts possess a distal appendix, and chordoid larval morphology varies among localities. These differences in morphology might indicate the existence of cryptic species. The presence of toes in the Prometheus larva could support a cycliophoran relationship with rotiferan taxa, although additional ultrastructural studies are needed. Considering that the genus Homarus is at least 60 My years old, and with regard to its history of speciation, it seems possible that the two Symbion species separated during the Pleistocene. © 2005 Gesellschaft für Biologische Systematik.
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| 13. |
- Pfeil, Bernard E., 1975, et al.
(författare)
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Recombination provides evidence for ancient hybridisation in the Silene aegyptiaca (Caryophyllaceae) complex
- 2017
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Ingår i: Organisms Diversity & Evolution. - : Springer Science and Business Media LLC. - 1439-6092 .- 1618-1077. ; 17:4, s. 717-726
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Tidskriftsartikel (refereegranskat)abstract
- Recombination events among distinct alleles complicate phylogenetic estimation. Various in vivo and in vitro processes can bring distinct alleles into the same genome to then undergo recombination, which may subsequently mislead phylogenetic inference if not assessed properly. Among the processes bringing divergent alleles together, hybridisation is perhaps the simplest and most likely, but alternatives need to be considered before hybridisation can be accepted as the underlying cause. Such alternatives include the presence of paralogues or deeply coalescing alleles, as well as amplification artefacts. Here, we document a recombination event that apparently took place between two divergent lineages of the Silene aegyptiaca complex in the flowering plant family Caryophyllaceae. We evaluate several possible mechanisms that might be responsible for the observed pattern. An ancient introgressive hybridisation event was the simplest explanation for the observations, compatible with geographic proximity of the affected lineages, whereas paralogy and deep coalescence are difficult to reconcile with the evidence obtained from a species tree of the group based on six different, non-recombinant genes and gene trees inferred using two partitions of the recombinant locus.
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| 14. |
- Raikova, Olga I., et al.
(författare)
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The plastic nervous system of Nemertodermatida
- 2016
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Ingår i: Organisms Diversity & Evolution. - : Springer Science and Business Media LLC. - 1439-6092 .- 1618-1077. ; 16:1, s. 85-104
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Tidskriftsartikel (refereegranskat)abstract
- Nemertodermatida are microscopic marine worms likely to be the sister group to acoels, forming with them the earliest extant branch of bilaterian animals, although their phylogenetic position is debated. The nervous system of Flagellophora cf. apelti, Sterreria spp. and Nemertoderma cf. westbladi has been investigated by immunohistochemistry and confocal microscopy using anti-tubulin, anti-5-HT and anti-FMRFamide antibodies. The nervous system of F. cf. apelti is composed of a large neuropile and a loose brain at the level of the statocysts with several nerve fibres surrounding them and innervating the broom organ. Sterreria spp. shows a commissural-like brain and several neurite bundles going frontad and caudad from this. At the level of the statocysts there is also a thicker aggregation of immunoreactive fibres. The nervous system of N. cf. westbladi consists of a nerve ring lying outside the body wall musculature at the level of the statocyst and a pair of ventro-lateral neurite bundles, from which extend thinner fibres innervating the ventral side of the animal. Numerous bottle-shaped glands were observed, innervated by fibres starting both from the brain and the neurite bundles. The nervous system of the nemertodermatids studied to date displays no common pattern; instead, there is considerable plasticity in the general morphology of the nervous system. In addition, the musculature of Sterreria spp. has been studied by phalloidin staining. It shows diagonal muscles in the anterior quarter of the body and a simple orthogonal grid in the posterior three quarters, being simpler than that of the other nemertodermatids. High-resolution differential interference contrast microscopy permitted to better visualize some morphological characters of the species studied, such as statocysts, sperm and glands and, in combination with anti-tubulin staining, describe in detail the broom organ in F. cf. apelti. Finally, we note an apparent absence of innervation of the gut in Nemertodermatida similar to the condition in Xenoturbella.
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| 15. |
- Riess, Kai, et al.
(författare)
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The origin and diversification of the Entorrhizales : deep evolutionary roots but recent speciation with a phylogenetic and phenotypic split between associates of the Cyperaceae and Juncaceae
- 2019
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Ingår i: Organisms Diversity & Evolution. - : SPRINGER HEIDELBERG. - 1439-6092 .- 1618-1077. ; 19:1, s. 13-30
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Tidskriftsartikel (refereegranskat)abstract
- Fungi belonging to the Entorrhizales (Entorrhizomycota) comprise biotrophic pathogens associated with roots of theCyperaceae and Juncaceae plant species. They are nearly globally distributed but rarely studied due to a hidden lifestyle without causing visible effects on host plants. Therefore, the evolutionary origin and phylogenetic relationships of the group are still poorly understood and it is not known whether species diversification was the result of co-evolution with their hosts or the result of host jumps. To infer hypotheses about the evolutionary history of the Entorrhizales, divergence times were estimated and plant-fungal tanglegrams calculated. Relaxed molecular clock analyses suggest that the Entorrhizomycota originated around the Neoproterozoic-Palaeozoic and diverged during the Late Cretaceous-Paleogene into the extant orders Entorrhizales and Talbotiomycetales. The split of the major lineages within the Entorrhizales took place in the Eocene, somewhat later than the divergence of the host families Cyperaceae and Juncaceae. Topology- and distance-based co-phylogenetic analyses of the fungi and their hosts revealed a large number of co-speciation and lineage sorting events in early fungal speciation, which resulted in a phylogenetic split corresponding to species infecting Cyperaceae or Juncaceae. Given that this split is congruent with spore differences, Entorrhiza s. str. is emended for species infecting hosts in the Cyperaceae, and a new genus Juncorrhiza is described for species restricted to hosts in the Juncaceae. Additionally, three new species are described: Entorrhiza fuirenae, Juncorrhiza maritima and J. oxycarpi.
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| 16. |
- Rota, E., et al.
(författare)
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Two new bioluminescent Henlea from Siberia and lack of molecular support for Hepatogaster (Annelida, Clitellata, Enchytraeidae)
- 2018
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Ingår i: Organisms Diversity & Evolution. - : Springer Science and Business Media LLC. - 1439-6092 .- 1618-1077. ; 18:3, s. 291-312
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Tidskriftsartikel (refereegranskat)abstract
- Two bioluminescent enchytraeids, Henlea petushkovi sp. n. and Henlea rodionovae sp. n., are described from the Krasnoyarsk and Irkutsk regions in Eastern Siberia. These large potworms exhibit the typical light-production pattern reported repeatedly in the genus and recently elucidated by Russian researchers in its main biophysical and biochemical aspects. Morphology and DNA indicate that the two species are very closely related, but clearly divergent in the strength of the body wall (thick and opaque in H. petushkovi), structure of the prostomium (in H. rodionovae unprecedentedly wrinkled and mobile), brain shape (almost equilateral in H. petushkovi), size of coelomocytes (60–85 μm in H. petushkovi) and structure of intestinal diverticula (tulip-shaped in H. petushkovi, apple-shaped in H. rodionovae). Limited hybridization seems to occur between them, supported by a single case of conflict between COI and morphology, and a few intermediate morphotypes were noted in greenhouse populations. The new species are phylogenetically distant from all known congeners so far DNA-barcoded, even those that, like them, respond to the diagnosis of the putative subgenus Hepatogaster Čejka, 1910 (multitubular gut diverticula in VIII, indented brain, dorsal blood vessel from IX, prominent spermathecal glands, and nephridia from 5/6). In fact, our phylogenetic analyses dismiss Hepatogaster as an artificial (polyphyletic) taxon. Issues related to the definition of H. nasuta (Eisen, 1878), H. ochracea (Eisen, 1878) and H. irkutensis Burov, 1929, three species originally described from Siberia, indicate that Henlea taxonomy is still in a state of flux, as regards not only species interrelationships but also species definitions.
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| 17. |
- Sawangproh, Weerachon, et al.
(författare)
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Morphological characters and SNP markers suggest hybridization and introgression in sympatric populations of the pleurocarpous mosses Homalothecium lutescens and H. sericeum
- 2020
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Ingår i: Organisms Diversity and Evolution. - : Springer Science and Business Media LLC. - 1439-6092 .- 1618-1077. ; 20:4, s. 619-637
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Tidskriftsartikel (refereegranskat)abstract
- Hybridization in bryophytes involves a fusion of gametes produced by haploid parental gametophytes of different species. The primary hybrid is thus the short-lived diploid sporophyte, which soon undergoes meiosis prior to the formation of large amounts of haploid spores. We compared morphology of gametophytes (branch leaves) and sporophytes (capsule inclination) from sympatric populations and allopatric populations of H. lutescens and H. sericeum. In addition, we used transcriptome data to select 85 nuclear SNP markers that were fixed for alternative alleles in the two species. The SNPs were used to estimate the degree of hybridization in diploid sporophytes. Our study shows that gametophytes from sympatric populations display intermediate morphology in a number of leaf characters, with exception for leaf sizes, which are markedly smaller than those in allopatric populations. None of the 100 sporophytes appeared to be primary hybrids, but 33 displayed admixing—heterozygotic expression of SNP markers or mismatch of occasional markers in homozygous condition—suggesting that extensive introgression takes place in the sympatric populations. Most sporophytes with intermediate capsule inclination, initially classed as putative hybrids, did not display admixture of nuclear SNP markers. Sixty-seven percent of admixed sporophytes have predominantly nuclear SNPs typical for H. lutescens. Our results suggest that interspecific hybridization and bidirectional introgression are relatively common in the studied sympatric populations, giving rise to viable recombinants, but not complete mixing of the parental genomes. Our study is one of the first detailed accounts of hybridization among pleurocarpous mosses, opening for future studies of gene transfer and introgression between bryophyte lineages and its role in local adaptation and long-term evolutionary diversification.
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| 18. |
- Stålstedt, Jeanette, et al.
(författare)
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Towards resolving the double classification in Erythraeus (Actinotrichida: Erythraeidae): matching larvae with adults using 28S sequence data and experimental rearing
- 2016
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Ingår i: Organisms Diversity & Evolution. - : Springer Science and Business Media LLC. - 1439-6092 .- 1618-1077. ; 16:4, s. 761-790
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Tidskriftsartikel (refereegranskat)abstract
- The taxonomy of free-living adults and heteromorphic parasitic larvae of Parasitengona mites has in the past been treated independently resulting in a double classification. Correct linkage of names still remains unknown for many species. A holistic understanding of species is imperative for understanding their role in ecosystems. This is particularly true for groups like parasitengone mites with a radically altered lifestyle during development-parasitic to predatory. Here, we infer linkages of three nominal species of Erythraeus, using matching with 28S DNA sequence data from field-collected specimens and through laboratory rearing. The general mixed Yule coalescent method (GMYC) was used to explicitly test if field-collected specimens representing heteromorphic life instars were conspecific. The field-collected larvae were allocated to adults of Erythraeus cinereus and Erythraeus regalis, respectively. Laboratory rearing of the same two species confirmed the matching done by DNA. Rearing was also successful for Erythraeus phalangoides after eggs were treated to an imitated winter diapause. This integrative taxonomic approach of molecular, morphological, and rearing data resulted in the following synonyms: E. phalangoides (De Geer, 1778) [= Erythraeus adrastus (Southcott, 1961), syn. nov.], E. cinereus (DugSs, 1834) [= Erythraeus jowitae Haitlinger, 1987, syn. nov.], and E. regalis (C.L. Koch, 1837) [= Erythraeus kuyperi (Oudemans, 1910), syn. nov., = Erythraeus gertrudae Haitlinger, 1987, syn. nov.]. The molecular evidence confirmed the separate identity of three further members of the genus. We provide redescriptions of E. phalangoides, E. cinereus, and E. regalis after modern standards, and neotypes are designated.
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| 19. |
- Svensson, Erik
(författare)
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Non-ecological speciation, niche conservatism and thermal adaptation: how are they connected?
- 2012
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Ingår i: Organisms Diversity & Evolution. - : Springer Science and Business Media LLC. - 1618-1077 .- 1439-6092. ; 12:3, s. 229-240
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Forskningsöversikt (refereegranskat)abstract
- During the last decade, the ecological theory of adaptive radiation, and its corollary "ecological speciation", has been a major research theme in evolutionary biology. Briefly, this theory states that speciation is mainly or largely the result of divergent selection, arising from niche differences between populations or incipient species. Reproductive isolation evolves either as a result of direct selection on mate preferences (e.g. reinforcement), or as a correlated response to divergent selection ("by-product speciation"). Although there are now many tentative examples of ecological speciation, I argue that ecology's role in speciation might have been overemphasised and that non-ecological and non-adaptive alternatives should be considered more seriously. Specifically, populations and species of many organisms often show strong evidence of niche conservatism, yet are often highly reproductively isolated from each other. This challenges niche-based ecological speciation and reveals partial decoupling between ecology and reproductive isolation. Furthermore, reproductive isolation might often evolve in allopatry before ecological differentiation between taxa or possibly through learning and antagonistic sexual interactions, either in allopatry or sympatry. Here I discuss recent theoretical and empirical work in this area, with some emphasis on odonates (dragonflies and damselflies) and suggest some future avenues of research. A main message from this paper is that the ecology of species differences is not the same as ecological speciation, just like the genetics of species differences does not equate to the genetics of speciation.
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| 20. |
- Teixeira, Marcos A.L., et al.
(författare)
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Revealing the diversity of the green Eulalia (Annelida, Phyllodocidae) species complex along the European coast, with description of three new species
- 2023
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Ingår i: Organisms Diversity and Evolution. - : Springer Science and Business Media LLC. - 1439-6092 .- 1618-1077. ; 23:3, s. 477-503
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Tidskriftsartikel (refereegranskat)abstract
- The green phyllodocids Eulalia clavigera and E. viridis are a known European pseudo-cryptic complex, but questions about its distribution and evidence of additional lineages in previous studies call for an investigation of the real diversity within the complex. We analyze DNA sequences (mtCOI-5P, ITS, and 28S rRNA) of different populations of E. clavigera from intertidal and subtidal marine waters along the North East Atlantic, Mediterranean Sea, theAzores and Webbnesia (Madeira, Savage islands andCanaries), and populations of E. viridis from the Scandinavia. This provided compelling evidence for the existence of six additional divergent evolutionary lineages, three of the most abundant being described here as new species: Eulalia feliciae sp. nov., intertidal and unique to the Western Mediterranean, Eulalia madeirensis sp. nov., subtidal and unique to the Madeira Island (Portugal), and Eulalia xanthomucosa sp. nov., mostly subtidal and occurring in the British Isles and southern France. Complementary morphometric analyses showed that E. feliciae sp. nov. and E. madeirensis sp. nov. formed two independent morphometric clusters, while E. xanthomucosa sp. nov. often overlapped with E. clavigera sensu stricto (s. s.), although being unique in showing a yellow coloration and parapodial cirri on median segments larger in relation to its body size. Recent biotechnological findings based on “E. clavigera” specimens highlight the importance of formally describing cryptic complexes, since each lineage chemistry might be unique and may have a range of distinct effects and applications.
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| 21. |
- Ware, Jessica, et al.
(författare)
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Evolution of reproductive strategies in libellulid dragonflies (Odonata: Anisoptera)
- 2012
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Ingår i: Organisms Diversity & Evolution. - Heidelberg : Springer Science and Business Media LLC. - 1618-1077 .- 1439-6092. ; 12:3, s. 313-323
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Tidskriftsartikel (refereegranskat)abstract
- In Libellulidae, oocyte production has been assumed to be continuous, with periods of egg-laying interspersed with periods of resting/eating; however, recent work suggests that two types of oocyte production are common: either (a) continuous or (b) step-wise. These are mirrored in the arrangement of the ovarioles in the ovaries. Likewise, two types of mate-guarding behavior have been observed in Libellulidae: (1) non-contact guarding and (2) tandem guarding in which the male either hovers above the female or is physically attached to her during oviposition. Using molecular (mitochondrial and nuclear) data we explored the evolution of female reproductive traits, focusing on ovariole morphology, as well as guarding behavior, in Libellulidae. Continuous egg production appears to have evolved more than once, as have tandem and non-contact guarding. We discuss how the evolution of different ovariole types and guarding behavior may have been influenced by habitat instability, dispersal and crowded oviposition sites; thus, migratory behavior or habitat availability may have been the driving force of ovariole evolution.
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| 22. |
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| 23. |
- Eriksson, Robert, et al.
(författare)
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Genetic evidence of phenotypic polymorphism in the aeolid nudibranch Flabellina verrucosa (M. Sars, 1829) (Opisthobranchia : Nudibranchia)
- 2006
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Ingår i: Organisms Diversity & Evolution. - : Elsevier BV. - 1439-6092. ; 6:1, s. 71-76
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Tidskriftsartikel (refereegranskat)abstract
- The conspecificity of two forms of Flabellina verrucosa (M. Sars, 1829), one form with short and one with long cerata, was tested by sequencing the mitochondrial COI and the nuclear 5.8S-ITS2 genes. We could not establish any genetic differences between the two forms and conclude that they belong to the same species. Thus, Flabellina verrucosa is polymorphic in ceratum length. (c) 2005 Gesellschaft fur Biologische Systematik. Published by Elsevier GmbH. All rights reserved.
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| 24. |
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| 25. |
- Giere, O., et al.
(författare)
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Questa (Annelida, Polychaeta, Orbiniidae) from Pacific regions – new species and a reassessment of the genus Periquesta
- 2008
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Ingår i: Organisms Diversity & Evolution. - : Elsevier BV. - 1439-6092. ; 7:4, s. 304-319
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Tidskriftsartikel (refereegranskat)abstract
- On the basis of new material from various Pacific regions we critically evaluate the characters for the taxonomy of the genus Questa and the former Questidae, a taxon now concluded to be a lineage within the family Orbiniidae. Two new species, Questa retrospermatica sp. n. from Hawaii (with similar forms also from New Caledonia and China), and Questa fijiensis sp. n. from Fiji, are described, and the morphological character patterns and phylogeny of the genus are revisited on the basis of a cladistic analysis. The finding of Hawaiian material of a new species, Levinsenia hawaiiensis sp. n., similar to Periquesta canariensis Brito & Nunez, 2002 (=Levinsenia canariensis comb. n.), challenges the view that Periquesta Brito & Nunez, 2002 is closely related to Questa; rather, it belongs to Paraonidae as a junior synonym of Levinsenia Mesnil, 1897.
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