403 research outputs found
Six new species of Macellicephala (Annelida: Polynoidae) from the Southern Ocean and south Atlantic with re-description of type species
No full textNeal, Lenka, Brasier, Madeleine J., Wiklund, Helena (2018): Six new species of Macellicephala (Annelida: Polynoidae) from the Southern Ocean and south Atlantic with re-description of type species. Zootaxa 4455 (1): 1-34, DOI: 10.11646/zootaxa.4455.1.
Ophryotrocha mammillata Ravara, Marcal, Wiklund & Hilario 2015
No full text<i>Ophryotrocha mammillata</i> Ravara, Marçal, Wiklund & Hilário, 2015 <p> <i>Ophryotrocha mammillata</i> Ravara <i>et al.</i>, 2015: 5, figs 4–12 (type locality: Setúbal Canyon, W Portugal, NE Atlantic).</p> Material examined <p>MOROCCO • 2 specs (ethanol), 1 spec. (slide preparation); GoC, Mercator MV, 35°17.916′ N, 06°38.709′ W; 354 m depth; 2 Mar. 2008; Stn 64PE284_12750W; wood substrata; DBUA0002279.01 • 1 spec. (ethanol); GoC, Meknès MV; 34°59.091′ N, 07°04.424′ W; 698 m depth; 20 May 2009; Stn B09- 14b_03A; alfalfa substratum; DBUA0002280.01 • 1 spec. (ethanol); GoC, Darwin MV; 35°23.523′ N, 07°11.513′ W; 1100 m depth; 19 May 2009; Stn B09-14b_02W; wood substratum; DBUA0002280.02 •</p> <p>2 specs (formalin), 3 specs (paragenophores, in ethanol); same collection data as for preceding; 19 May 2009; Stn B09-14b_02A; alfalfa substrata; DBUA 0002280.03.</p> <p> <b>Additional material</b></p> <p>PORTUGAL • 2 specs (ethanol); WIM, Setúbal Canyon; 38°16.856′ N, 09°06.734′ W; 1000 m depth; 22 Aug. 2012; on bone material from an experimentally deployed cow carcass; DBUA0001555.04.</p> Remarks <p> This species was recently described from an experimentally deployed mammal carcass for a similar amount of time (approximately 18 months) at the Setúbal Canyon (WIM) (Ravara <i>et al.</i> 2015). The morphological identification was confirmed with molecular analyses (Fig. 2). This study extends its distribution to the Gulf of Cadiz where it occurred associated with experimentally deployed wood and alfalfa substrata. Curiously, <i>O. mammillata</i> was not found in the wood-fall collected at Estremadura Spur (WIM), a site very close to its type locality. It is worth mentioning here that in the GoC only five specimens of <i>O. mammillata</i> were retrieved, compared to 198 specimens previously reported from the Setúbal Canyon (Ravara <i>et al</i>. 2015).</p> Ecology and distribution <p> NE Atlantic: from Setúbal Canyon (West Iberian Margin) to the Gulf of Cadiz. Found in experimentally deployed organic falls (mammal carcasses, wood and alfalfa substrata), at a depth of 354–1100 m (Ravara <i>et al.</i> 2015; present study).</p>Published as part of <i>Ravara, Ascensão, Wiklund, Helena & Cunha, Marina R., 2021, Four new species and further records of Dorvilleidae (Annelida, Polychaeta) from deep-sea organic substrata, NE Atlantic, pp. 44-81 in European Journal of Taxonomy 736</i> on pages 63-64, DOI: 10.5852/ejt.2021.736.1251, <a href="http://zenodo.org/record/4570204">http://zenodo.org/record/4570204</a>
Ophryotrocha scutellus Wiklund, Glover & Dahlgren 2009
No full textOphryotrocha scutellus Wiklund, Glover & Dahlgren, 2009 Figs 11–12 Material examined MOROCCO • 11specs (plus2cf.)(formalin), 2specs (slide preparation);GoC,Mercator MV; 35°17.916′N, 06°38.709′ W; 354 m; 2 Mar. 2008; Stn 64PE284_12750W; wood substrata; DBUA0002288.01 • 1 spec. cf. (formalin); same locality as for preceding; 3 Mar. 2008; Stn 64PE284_12752A; alfalfa substratum; DBUA0002288.02 • 1 spec. (ethanol); same collection data as for preceding; 19 May 2009; Stn B09- 14b_01W; wood substratum; DBUA0002287.05 • 1 spec. (ethanol), 7 specs (formalin), 3 specs (slide preparation); GoC, Meknès MV; 34°59.091′ N, 07°04.424′ W; 698 m; 20 May 2009; Stn B09-14b_03W; wood substrata; DBUA0002287.03 • 3 specs (ethanol), 1 spec. (formalin); same locality and date as for preceding; Stn B09-14b_03A; alfalfa substrata; DBUA0002287.04 • 4 specs (ethanol), 1 spec. (formalin), 1 spec. (slide preparation, hologenophore); GoC, Darwin MV; 35°23.523′ N, 07°11.513′ W; 1100 m; 19 May 2009; Stn B09-14b_02A; alfalfa substrata; DBUA0002287.01 • 1 spec. (ethanol); same locality and date as for preceding; Stn B09-14b_02C; carbonate substratum; DBUA0002287.02. Additional material PORTUGAL • 6 specs (ethanol); WIM, Setúbal Canyon; 38°16.856′ N, 09°06.734′ W; 1000 m depth; 22 Aug. 2012; on bone material from a cow carcass; DBUA0001557.01-02. SWEDEN • 12 specs (ethanol); coastal Skagerrak; 58°53.1′ N, 11°06.4′ E; 125 m depth; on bone material from a minke whale carcass; DBUA0002348. Description (amended) Size of WIM and GoC specimens varies within 1.55–2.70 mm long and 0.24–0.39 mm wide for 18–24 chaetigers. Skagerrak specimens are larger, up to 3.60 mm long and 0.75 mm wide for 31 chaetigers (Fig. 3). Body dorso-ventrally flattened, with similar width throughout the body, abruptly ending with pygidium in smaller specimens (Fig. 11A) or tapering slightly at posterior end in larger ones. Prostomium broadly rounded, dorso-ventrally flattened, with a transverse ridge between the antennae, without eyes (Fig. 11A). Antennae and palps long, digitiform; antennae inserted mid-dorsally on the prostomium; palps inserted laterally. Peristomium achaetous, with two rings slightly narrower and shorter than the following segments. Jaw apparatus heavily sclerotized, well visible through the specimen body, usually with an apparent rhombus shape (Fig. 11 A–B).The morphology of mandibles and maxillary forceps varies with the specimen size (Fig. 12 A–J). Mandibles rod-like; smaller specimens with straight and clearly dentate anterior end and long apophyse, well surpassing the cutting edge, with a diagonal connection to the shaft (Fig. 12A); with growth, the teeth wear out (Fig. 12B) and the cutting edge becomes short and more curved forward, without teeth, the apophyse becomes thicker with an almost vertical connection to the shaft (Fig. 12 D–E). Maxillae of P-type; forceps falcate, comb-like, slightly wider with up to 20 large teeth on the right side, and narrower with up to 26 thinner teeth on the left side (Fig. 12 F–G); with growth, the teeth of the left forcep become irregular (Fig. 12H) resulting in a clear alternation in size in larger specimens (Figs 11D, 12 I–J); eleven free denticles (D1–11), D1 similar to forceps (always with even teeth), D2 to D11 shovel-like, D4 to D11 usually directed inwards (Fig. 11 H–I); carrierlike structure with a toothed ridge on each side near the forceps (see details in Fig. 11D) and with a posteriorly fimbriate handle (Fig. 11D). Parapodia uniramous (Fig. 11C); pre-chaetal lamellae of median parapodia very long, cirriform; dorsal and ventral cirri digitiform, long (dorsal longer than ventral); sub-acicular lobes conical, about two-thirds the length of pre-chaetal lamellae in smaller specimens, becoming shorter in larger specimens (Fig. 12 K–N), with a needle-like acicula (Fig. 11E). Chaetae long and stiff; supra-acicular chaetae simple, slightly flattening and tapering distally to a fine tip, very lightly serrated, 7 per fascicle (Fig. 11G); sub-acicular chaetae compound with bifurcate, sub-distally serrated shafts, and falcate, very lightly serrated blades (Fig. 11F), 7–9 per fascicle. Pygidium with terminal anus, a pair of cirriform anal cirri and a very short (almost imperceptible) median stylet. Remarks This species was originally described from a minke whale carcass deployed at a depth of 125 m off Sweden and organically enriched sediments beneath a fish farm in Norway, at a depth of 104 m (Wiklund et al. 2009). Later, seven specimens of the same species were retrieved from an experimentally implanted cow carcass at the Setúbal Canyon (WIM), 1000 m depth (Ravara et al. 2015). The present study extends the distribution of O. scutellus to GoC where it occurred associated with experimentally deployed alfalfa and wood substrata and control samples (carbonate cubes), at a depth of 354–1100 m. The specimens from the GoC and WIM are overall smaller than the ones originally described from Sweden and Norway (Fig. 3) and exhibit some variation in the mandibular and maxillary morphology, apparently associated with growth (Fig. 12). However, the larger specimens of the southern locations entirely match the morphology of the northern ones. The morphological identification was furthermore confirmed with molecular analyses for both the larger and the smaller specimens. The specimen from GoC (DBUA0002287.01) sequenced here falls among previously published O. scutellus sequences (Genbank accession numbers GQ415506 and KP731544 -48) with within-species K2P values from the H3 alignment of 0.009–0.01, and a K2P value of 0.10 to the nearest species in the tree, O. chemecoli sp. nov. A similar variability in length and corresponding variation in the mandible morphology has earlier been described for other species, such as O. sadina and O. lusa (Ravara et al. 2015: figs 15, 25, respectively). Differing from what was stated in the original description, the specimens of O. scutellus studied here have eleven pairs of free denticles (instead of seven) in the maxillary apparatus, and the left forcep of the larger specimens have uneven teeth. These characters were also found in the specimens from off Sweden examined here (Figs 11–12). Thus, the original description is here amended accordingly. Ecology and distribution NE Atlantic: from Norway to the Gulf of Cadiz (Moroccan Margin). Found in mammal carcasses, organically enriched sediment beneath fish farms, wood, alfalfa and carbonate substrata, at a depth of 104–1100 m (Wiklund et al. 2009; Ravara et al. 2015; present study).Published as part of Ravara, Ascensão, Wiklund, Helena & Cunha, Marina R., 2021, Four new species and further records of Dorvilleidae (Annelida, Polychaeta) from deep-sea organic substrata, NE Atlantic, pp. 44-81 in European Journal of Taxonomy 736 on pages 67-70, DOI: 10.5852/ejt.2021.736.1251, http://zenodo.org/record/457020
FIGURE 5 in A new species of Raricirrus (Annelida: Cirratuliformia) from deep-water sunken wood off California
No full textFIGURE 5. Phylogenetic tree from the Bayesian analysis of a combined dataset with 16S and COI using in total 32 cirratuliform polychaetes. Numbers on branches are posterior probability values.Published as part of Magalhães, Wagner F., Linse, Katrin & Wiklund, Helena, 2017, A new species of Raricirrus (Annelida: Cirratuliformia) from deep-water sunken wood off California, pp. 51-68 in Zootaxa 4353 (1) on page 61, DOI: 10.11646/zootaxa.4353.1.3, http://zenodo.org/record/106450
An operationalization of Stevenson’s conceptualization of entrepreneurship as opportunity-based firm behavior
No full textThis is the author-version of article published as: Brown, Terrence and Davidsson, Per and Wiklund, Johan (2001) An operationalization of Stevenson’s conceptualization of entrepreneurship as opportunity-based firm behavior. Strategi
FIGURE 3 in Six new species of Macellicephala (Annelida: Polynoidae) from the Southern Ocean and south Atlantic with re-description of type species
No full textFIGURE 3 Macellicephala mirabilis (holotype, BMNH 1885: 12: 1: 100; specimen in two fragments): A) anterior fragment in dorsal view; B) posterior fragment of specimen in dorsal view; C) detail of prostomium in dorsal view; D) ventral view with nephridial papillae on segments 10–12 marked by arrows; E) detail of pygidium in ventral view. All scale bars 1 mm.Published as part of Neal, Lenka, Brasier, Madeleine J. & Wiklund, Helena, 2018, Six new species of Macellicephala (Annelida: Polynoidae) from the Southern Ocean and south Atlantic with re-description of type species, pp. 1-34 in Zootaxa 4455 (1) on page 9, DOI: 10.11646/zootaxa.4455.1.1, http://zenodo.org/record/145691
FIGURE 16 in Six new species of Macellicephala (Annelida: Polynoidae) from the Southern Ocean and south Atlantic with re-description of type species
No full textFIGURE 16. Macellicephala linseae sp. nov. (holotype, NHMUK.2018.9354): A) holotype – complete specimen in dorsal view; B) detail of prostomium in dorsal view, C) DNA voucher specimen in dorsal view, showing details of circular and semicircular dorsal ridges. All scale bars: 1.5mm.Published as part of Neal, Lenka, Brasier, Madeleine J. & Wiklund, Helena, 2018, Six new species of Macellicephala (Annelida: Polynoidae) from the Southern Ocean and south Atlantic with re-description of type species, pp. 1-34 in Zootaxa 4455 (1) on page 27, DOI: 10.11646/zootaxa.4455.1.1, http://zenodo.org/record/145691
FIGURE 10 in Six new species of Macellicephala (Annelida: Polynoidae) from the Southern Ocean and south Atlantic with re-description of type species
No full textFIGURE 10. Macellicephala patersoni sp. nov. (holotype, NHMUK.2018.1009): A) mid body parapodium; B) notochaetae; C) detail of notochaetae; D–H) neurochaetae. Scale bars: A) 500 µm; B) 300 µm; C–E) 100 µm; F–G) 50 µm and H) 15 µm.Published as part of Neal, Lenka, Brasier, Madeleine J. & Wiklund, Helena, 2018, Six new species of Macellicephala (Annelida: Polynoidae) from the Southern Ocean and south Atlantic with re-description of type species, pp. 1-34 in Zootaxa 4455 (1) on page 20, DOI: 10.11646/zootaxa.4455.1.1, http://zenodo.org/record/145691
Vrijenhoekia balaenophila, a new hesionid polychaete from a whale fall off California
No full textPleijel, Fredrik, Rouse, Greg W., Ruta, Christine, Wiklund, Helena, Nygren, Arne (2008): Vrijenhoekia balaenophila, a new hesionid polychaete from a whale fall off California. Zoological Journal of the Linnean Society 152 (4): 625-634, DOI: 10.1111/j.1096-3642.2007.00360.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2007.00360.
Cryptic speciation at organic-rich marine habitats: a new bacteriovore annelid from whale-fall and fish farms in the North-East Atlantic
No full textWiklund, Helena, Glover, Adrian G., Johannessen, Per J., Dahlgren, Thomas G. (2009): Cryptic speciation at organic-rich marine habitats: a new bacteriovore annelid from whale-fall and fish farms in the North-East Atlantic. Zoological Journal of the Linnean Society 155 (4): 774-785, DOI: 10.1111/j.1096-3642.2008.00469.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2008.00469.
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