Endre Willassen

University of Bergen

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Torbjørn Ekrem

Norwegian University of Science and Technology

Gaute Velle

NORCE Norwegian Research Centre

Jon Anders Kongsrud

University of Bergen

H. J. B. Birks

Bjerknes Centre for Climate Research

Trond R. Oskars

University of Bergen

Steffen Roth

University Hospital Heidelberg

Kenneth Meland

University of Bergen

Klaus Reinhardt

University of Sheffield

Nataliya Budaeva

University of Bergen

Ondřej Balvín

Czech University of Life Sciences Prague

Cooperative Institutions

University of Bergen

Norwegian Institute of Marine Research

Natural History Museum

Norwegian University of Science and Technology

University of Łódź

Centre National de la Recherche Scientifique

University of Duisburg-Essen

UiT The Arctic University of Norway

Vitensenteret i Trondheim

Naturalis Biodiversity Center

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DNA-barcoding Decapoda and Stomatopoda from West-Africa

Endre Willassen E. García-Isarch S.S. de Matos-Pita

DNA Barcoding

Ciguatera

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Lumping lumpsuckers: molecular and morphological insights into the taxonomic status of Eumicrotremus spinosus (Fabricius, 1776) and Eumicrotremus eggvinii Koefoed, 1956 (Teleostei: Cyclopteridae)

Journal of Fish Biology (2007)

Ingvar Byrkjedal D. Rees Endre Willassen

The genus Eumicrotremus comprises 16 lumpsucker species distributed in the Arctic and northern Atlantic and Pacific Oceans. The most common species in the North Atlantic is Eumicrotremus spinosus , described in 1776, and characterized partly by numerous bony tubercles on the head and body. Another Atlantic species, Eumicrotremus eggvinii , described in 1956, remained known only from a single specimen until additional specimens were recently recovered. To reassess the status of E. eggvinii , 21 meristic and 32 morphometric characters were analysed for a total of 83 specimens of E. spinosus and E. eggvinii . Mitochondrial (COI, COII and cyt‐ b ) and nuclear ( Tmo‐4C4 ) genes were also sequenced for both species, along with Eumicrotremus derjugini . The results indicate that although E. spinosus and E. eggvinii are clearly separated by a considerable number of morphological characters, they in fact constitute a single, sexually dimorphic species. Thirteen specimens of E. eggvinii (including the holotype) and 59 E. spinosus could be sexed; all individuals of E. eggvinii turned out to be males and all E. spinosus were females. Identical DNA sequences were found in all E. eggvinii and E. spinosus for COI, COII and Tmo‐4C4 , and a single shared synonymous substitution found in cyt‐ b . In contrast, E. spinosus , E. eggvinii and E. derjugini differed by 5·9% for COI and COII, 1·2% for Tmo‐4C4 and 8·3% for cyt‐ b .

Meristics

Teleostei

10.1111/j.1095-8649.2007.01550.x

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Citations (27)

A new oriental speciesof Diamesameigen (Diptera: Chironomidae)

Aquatic Insects (1988)

Endre Willassen

The male and female imagines of Diamesa cranstoni sp.n. collected on Mt. Kinabalu, Sabah, Borneo, are described.

10.1080/01650428809361333

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Citations (1)

Redescription of Micropsectra borealis (Kieffer, 1922) n.comb. (Diptera: Chironomidae)

Insect Systematics & Evolution (1980)

Endre Willassen Lars Säwedal

Abstract The first description of the pupa of Micropsectra borealis (Kieffer, 1922) and a redescription of the imago ♂ is presented. The genus Oeklandia Kieffer, 1922 is synonymised with the genus Micropsectra Kieffer, 1909. The possible synonymy between Oeklandia and the genus Himatendipes Tokunaga, 1959 is indicated. Together with M. coracina (to be treated in a future paper by the senior author) and the atrofasciata-bidentata-group, the species form a monophyletic group within the genus Micropsectra. The pupa of M. borealis shows great variation in the number of lateral setae on the margin of the segments. Often the numbers differ between the two sides of the segment, a state of character not previously reported from the Tanytarsini. The ecology of M. borealis is discussed.

Imago

Monophyly

Entomology

10.1163/187631280x00365

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Citations (6)

A molecular phylogeny of the gastropod family Haminoeidae sensu lato (Heterobranchia: Cephalaspidea): a generic revision

Invertebrate Systematics (2019)

Trond R. Oskars Chin Chin Too D. Rees Paula M. Mikkelsen Endre Willassen

Haminoeidae is the most diverse family of Cephalaspidea with 13 to 17 genera commonly recognised as valid and with 46 genera that historically have been moved back and forth between Haminoeidae and other families. Due to poor definition of most genera the family is plagued by extensive taxonomic confusion and its generic composition and internal relationships remain uncertain. In this work we have integrated the study of type material, original descriptions, shells, morpho-anatomical data, and molecular phylogenetics (Bayesian, maximum likelihood, and maximum parsimony) based on five genetic markers (the mitochondrial genes cytochrome c oxidase subunit I and 16SrRNA and the nuclear genes 18SrRNA, 28SrRNA, and histoneH3) to delimit the valid genera, define synapomorphic traits, and establish synonym lists. Three hundred and ninety novel sequences were generated. In total 14 genera were recognised; one genus (Vellicolla gen. nov.) is here described as new and an additional fifteenth group was identified, but no species could be formally ascribed to it and therefore remains unnamed (here designated informally as mini-haminoeids). The relationships of genera are discussed and seven deep clades have been identified but are not formally named because of lack of recognisable synapomorphies for several of them. A new classification for Haminoeidae is proposed including 14 valid genera and one informal group.

Synapomorphy

Sensu

PhyloCode

Molecular Phylogenetics

10.1071/is18051

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Citations (23)

Molecular phylogeny of Caudofoveata (Mollusca) challenges traditional views

Molecular Phylogenetics and Evolution (2018)

Nina T. Mikkelsen Christiane Todt Kevin M. Kocot Kenneth M. Halanych Endre Willassen

Monophyly

Molecular Phylogenetics

Sister group

10.1016/j.ympev.2018.10.037

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Citations (17)

Mitogenomic sequences and evidence from unique gene rearrangements corroborate evolutionary relationships of myctophiformes (Neoteleostei)

BMC Evolutionary Biology (2013)

Jan Yde Poulsen Ingvar Byrkjedal Endre Willassen D. Rees Hirohiko Takeshima

A skewed assemblage of two epi-, meso- and bathypelagic fish families makes up the order Myctophiformes – the blackchins Neoscopelidae and the lanternfishes Myctophidae. The six rare neoscopelids show few morphological specializations whereas the divergent myctophids have evolved into about 250 species, of which many show massive abundances and wide distributions. In fact, Myctophidae is by far the most abundant fish family in the world, with plausible estimates of more than half of the oceans combined fish biomass. Myctophids possess a unique communication system of species-specific photophore patterns and traditional intrafamilial classification has been established to reflect arrangements of photophores. Myctophids present the most diverse array of larval body forms found in fishes although this attribute has both corroborated and confounded phylogenetic hypotheses based on adult morphology. No molecular phylogeny is available for Myctophiformes, despite their importance within all ocean trophic cycles, open-ocean speciation and as an important part of neoteleost divergence. This study attempts to resolve major myctophiform phylogenies from both mitogenomic sequences and corroborating evidence in the form of unique mitochondrial gene order rearrangements. Mitogenomic evidence from DNA sequences and unique gene orders are highly congruent concerning phylogenetic resolution on several myctophiform classification levels, corroborating evidence from osteology, larval ontogeny and photophore patterns, although the lack of larval morphological characters within the subfamily Lampanyctinae stands out. Neoscopelidae is resolved as the sister family to myctophids with Solivomer arenidens positioned as a sister taxon to the remaining neoscopelids. The enigmatic Notolychnus valdiviae is placed as a sister taxon to all other myctophids and exhibits an unusual second copy of the tRNA-Met gene – a gene order rearrangement reminiscent of that found in the tribe Diaphini although our analyses show it to be independently derived. Most tribes are resolved in accordance with adult morphology although Gonichthyini is found within a subclade of the tribe Myctophini consisting of ctenoid scaled species. Mitogenomic sequence data from this study recognize 10 reciprocally monophyletic lineages within Myctophidae, with five of these clades delimited from additional rearranged gene orders or intergenic non-coding sequences. Mitogenomic results from DNA sequences and unique gene orders corroborate morphology in phylogeny reconstruction and provide a likely scenario for the phylogenetic history of Myctophiformes. The extent of gene order rearrangements found within the mitochondrial genomes of myctophids is unique for phylogenetic purposes.

Sister group

Subfamily

10.1186/1471-2148-13-111

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Citations (67)

Kunnskapsstatus for bruk av molekylære verktøy i kartlegging og overvåkning av biologisk mangfold i marine miljø

76 (2021)

Glenn Dunshea Luis Martell Torkild Bakken Nataliya Budaeva Torbjørn Ekrem

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Vibrio tapetis-like strain isolated from introduced Manila clams Ruditapes philippinarum showing symptoms of brown ring disease in Norway

Diseases of Aquatic Organisms (2008)

Christine Paillard Kjetil Korsnes Patrick Le Chevalier C. Le Boulay Lisbeth S. Harkestad

The Manila clam Ruditapes philippinarum was introduced to Norway in 1987 and was produced in 2 hatcheries until 1991. Clam seed was planted at 6 sites. Two sites were on the Island of Tysnes, south of Bergen. Surviving adult Manila clams were recovered in 1995 and 1996. In the present study, Manila clams from the original seeding that displayed morphological signs of brown ring disease (BRD) were recovered in June 2003 (n=7) and in June 2004 (n=17). Samples from extrapallial fluid, tissues and haemolymph were inoculated on marine agar. Replicate subcultures on selective media were used to select potential Vibrio tapetis strains, and in total, 190 bacterial strains were isolated. One of these strains clustered within the V tapetis clade and was named NRP 45. DNA:DNA hybridisation with the type strain CECT4600 showed 52.7 and 57.3% DNA:DNA similarity. Hybridisation of NRP 45 and the V tapetis LP2 strain, isolated from corkwing wrasse Symphodus melops, produced 46.6 and 44.4% re-association. Partial gene segments encoding 16S rRNA, gyrase B protein (GyrB) and chaperonin 60 protein (Cpn60) were characterised and compared to CECT 4600. NRP 45 showed 5 differences in the 1416 nucleotides (nt) of the 16S rRNA encoding gene (99.6% similarity), while the GyrB encoding gene had 62 substitutions of 1181 nt compared (94.8% similarity) and the Cpn60 encoding gene had 22 substitutions out of 548 nt compared (96% similarity). This is the first finding of BRD and the first isolation of a V. tapetis-like bacterial strain from a bivalve in Norway.

Ruditapes

10.3354/dao01950

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Citations (31)

Local scale DNA barcoding of bivalves (Mollusca): a case study

Zoologica Scripta (2007)

Nina T. Mikkelsen Christoffer Schänder Endre Willassen

Divergence in cytochrome c oxidase 1 (COI), the genetic marker proposed for DNA barcoding, was investigated in marine bivalves from the genera Ennucula , Nucula , Yoldiella and Thyasira . No overlap in levels of intra‐ and interspecific variation was found. The levels of divergence found suggest that barcodes from COI will be useful in distinguishing between the species investigated in this study. The insufficiency of blast searches in GenBank to assign many of the obtained sequences to correct phylum was noted and clearly demonstrates the need for better search strategies specifically targeted at identification using DNA barcodes.

DNA Barcoding

Genetic divergence

Divergence (linguistics)

10.1111/j.1463-6409.2006.00289.x

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Citations (70)