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FIGURE 6. Tetilla sibirica. A, C in Sponge (Porifera) fauna of Frobisher Bay, Baffin Island, Canada with the description of an Iophon rich sponge garden
No full textFIGURE 6. Tetilla sibirica. A, C. Sponge in situ with echinoderms attached, scale bars are 6 cm. B, D. Specimen collected. E, K. Anatriaenes. F. Small oxea. G, H. Sigmaspires. I. Protriaene. J. Large Oxea.Published as part of Dinn, Curtis, Edinger, Evan & Leys, Sally P., 2019, Sponge (Porifera) fauna of Frobisher Bay, Baffin Island, Canada with the description of an Iophon rich sponge garden, pp. 301-325 in Zootaxa 4576 (2) on page 316, DOI: 10.11646/zootaxa.4576.2.5, http://zenodo.org/record/262495
FIGURE 5. Mycale lingua. A. Specimen collected. B in Sponge (Porifera) fauna of Frobisher Bay, Baffin Island, Canada with the description of an Iophon rich sponge garden
No full textFIGURE 5. Mycale lingua. A. Specimen collected. B. Sponge in situ, scale bar is 6 cm. C, D. Style/mycalostyles. E–G. Anisochelae I. H–J. Anisochelae II. K. Sigma. L. Raphide.Published as part of Dinn, Curtis, Edinger, Evan & Leys, Sally P., 2019, Sponge (Porifera) fauna of Frobisher Bay, Baffin Island, Canada with the description of an Iophon rich sponge garden, pp. 301-325 in Zootaxa 4576 (2) on page 314, DOI: 10.11646/zootaxa.4576.2.5, http://zenodo.org/record/262495
Sponge (Porifera) fauna of Frobisher Bay, Baffin Island, Canada with the description of an Iophon rich sponge garden
No full textDinn, Curtis, Edinger, Evan, Leys, Sally P. (2019): Sponge (Porifera) fauna of Frobisher Bay, Baffin Island, Canada with the description of an Iophon rich sponge garden. Zootaxa 4576 (2): 301-325, DOI: 10.11646/zootaxa.4576.2.
Figure 3 in Morphology and composition of the internal axis in two morphologically contrasting deep-water sea pens (Cnidaria: Octocorallia)
No full textFigure 3. Pieces of axis showing surface texture at different sections of a same specimen of Umbellula encrinus (a, sample ID 052) and Anthoptilum grandiflorum (b) from base to distal tip. Pencil marking can be seen in red. Scale bars = 5 cm.Published as part of de Moura Neves, Bárbara, Edinger, Evan & Wareham Hayes, Vonda, 2018, Morphology and composition of the internal axis in two morphologically contrasting deep-water sea pens (Cnidaria: Octocorallia), pp. 659-685 in Journal of Natural History 52 (11-12) on page 665, DOI: 10.1080/00222933.2018.1445787, http://zenodo.org/record/517431
FIGURE 2 in Sponge (Porifera) fauna of Frobisher Bay, Baffin Island, Canada with the description of an Iophon rich sponge garden
No full textFIGURE 2. Examples of the diversity of sponges, associated animals, and of substrate types in Frobisher Bay recorded during an ROV dive near Hill Island. A. Crinoids and ophiuroids perch on a sandy bottom. B. The sponge Tetilla sibirica with seastar, crinoids, and other sponges attached. C. Solitary tunicates and loose kelp (green). D. Tunicates and the sponge Iophon koltuni with Arcturus baffini isopods attached. E. A garden of I. koltuni. F, G. Sponges growing on bedrock outcrops. Scale bars 6 cm.Published as part of Dinn, Curtis, Edinger, Evan & Leys, Sally P., 2019, Sponge (Porifera) fauna of Frobisher Bay, Baffin Island, Canada with the description of an Iophon rich sponge garden, pp. 301-325 in Zootaxa 4576 (2) on page 306, DOI: 10.11646/zootaxa.4576.2.5, http://zenodo.org/record/262495
Arctic sea-ice decline archived by multicentury annual-resolution record from crustose coralline algal proxy
No full textNorthern Hemisphere sea ice has been declining sharply over the past decades and 2012 exhibited the lowest Arctic summer sea-ice cover in historic times. Whereas ongoing changes are closely monitored through satellite observations, we have only limited data of past Arctic sea-ice cover derived from short historical records, indirect terrestrial proxies, and low-resolution marine sediment cores. A multicentury time series from extremely long-lived annual increment-forming crustose coralline algal buildups now provides the first high-resolution in situ marine proxy for sea-ice cover. Growth and Mg/Ca ratios of these Arctic-wide occurring calcified algae are sensitive to changes in both temperature and solar radiation. Growth sharply declines with increasing sea-ice blockage of light from the benthic algal habitat. The 646-y multisite record from the Canadian Arctic indicates that during the Little Ice Age, sea ice was extensive but highly variable on subdecadal time scales and coincided with an expansion of ice-dependent Thule/Labrador Inuit sea mammal hunters in the region. The past 150 y instead have been characterized by sea ice exhibiting multidecadal variability with a long-term decline distinctly steeper than at any time since the 14th century
Enigmatic deep-water mounds on the Orphan Knoll, Labrador Sea
Full text linkDeep-sea mounds can have a variety of origins and may provide hard-substrate features in depths that are normally dominated by mud. Orphan Knoll, a 2 km high bedrock horst off northeast Newfoundland, hosts more than 200 mounds, or mound complexes, of unknown composition, in water depths of 1720–2500 m. Most mounds are 10–600 m high, with average mound height 187 m, and 1–3 km wide. The study objective was to characterize the size, shape, orientation, and composition of the enigmatic Orphan Knoll mounds, in order to determine their age and origin. Archival ship-based side-scan sonar, multibeam sonar, airgun, high-resolution sparker and 3.5 kHz acoustic sub-bottom profiling, and newly acquired ship-based multibeam sonar, video transects by remotely operated vehicle (ROV), rock samples, and near-bottom multibeam sonar data were analyzed. Four mounds were studied during two ROV dives. Archival sidescan sonar data show > 200 mounds. Sparker profiles show that the mound crests are covered by condensed stratified Quaternary sediment and airgun seismic data show faults reaching near the seafloor. New multibeam sonar data show mounds are dominantly conical to elliptical in shape, but without preferred orientation or alignment. Remotely operated vehicle (ROV) transects and near-bottom multibeam showed that three mounds were rounded and symmetrically arranged, while a fourth was more asymmetrical, with steep faces on the southwestern and southeastern flanks, where finely bedded to massive sedimentary bedrock outcropped dipping 15–45°SW. Rock samples from the mounds include Eocene calcareous ooze and mid-Miocene bedded pelagic limestone. Thick ferromanganese crusts were found on many surfaces, obscuring possible outcrops from physical sampling. Polymetallic nodules were found on the slope of one mound. Ice-rafted detritus, including igneous and metamorphic rocks and Paleozoic limestone and dolostone, was common in the sediments immediately surrounding the mounds. Quaternary sub-fossil solitary scleractinian corals accumulated over a span of at least 0.18 Ma at the base of one mound. The presence of uplifted condensed Eocene-Miocene rocks on the mounds and faulting in seismic profiles suggest uplift during reactivation of old rift-related faults during the Neogene, with seabed mass wasting creating residual mounds, which were then draped by Quaternary proglacial muds. Sculpting of hemipelagic Quaternary sediment by bottom currents probably contributed to mound morphology
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Mycale (Mycale) lingua Bowerbank 1866
No full textMycale (Mycale) lingua Bowerbank, 1866 Figure 5; Table 5 Synonymy: Hymeniacidon lingua Bowerbank, 1866: 187 –190. Desmacidon constrictus Bowerbank, 1866: 187 –190. Esperella vosmaeri Levinsen, 1887: 358 –359 pl.XXX fig 11–14. Esperia lucifera Schmidt 1873: 148. Esperia placoides Carter 1876: 316 –317; pl XIII fig 12, pl XV fig 32. Mycale (Mycale) lingua: Topsent 1924: 85 –88, Ackers et al. 1992: 111 –112., Boury-Esnault et al. 1994: 96, fig. 70. Van Soest et al. 2014: 99. Material examined. CMNI 2018-0167, s pecimen in 95% ethanol. Collected by Agassiz Trawl July 14, 2017, 402 m depth (62° 57.232’ N, 67° 08.360’ W). Specimens collected outside of Frobisher Bay: CMNI 2018-0053, specimen in 95% ethanol. Collected by Curtis Dinn with BX 650 MK III box core July 15, 2016, 459m depth (63° 06.67’ N, 67°31.10’ W). CMNI 2018 - 0 0 71, s pecimen in 95% ethanol. Collected by ROV hydraulic manipulator July 19, 2016, 631 m depth (61° 26.417’ N, 60° 39.8484’ W). CMNI 2018-0152, specimen in 95% ethanol. Collected by Curtis Dinn by ROV hydraulic manipulator July 25, 2016, depth 876 m (67° 58.0424’ N, 59° 29.0396’ W). CMNI 2018-0196, specimen in 95% ethanol. Collected by Agassiz trawl July 25, 2017, 333 m depth (76° 19.020’ N, 75° 46.225’ W). All operations performed from the CCGS Amundsen in Frobisher Bay and Davis Strait, Canada. Description. Specimens are bright yellow with a characteristic fibrous root and soft, furrowed distal portion (Fig. 5 A–B). Spicules (Fig. 5 C–L) consist of styles/mycalostyles 514 (400–590) x 16 (12–20) µm; sigmas 20 (14.5–26) µm, anisochelae I 73 (52–88) µm; anisochelae II 37.5 (28.5–50) µm; and raphides which were rare and did not form conspicuous trichodragmas in the Frobisher Bay specimens 43 (30–53) µm n=16. Interestingly, some modified anisochelae were present where the alae were not fully developed (Fig. 5G, H). These spicules occurred in both size categories, but only in the Frobisher Bay specimens. Taxonomic Remarks. The spicule sizes of this specimen correspond to descriptions of M. lingua by Ackers et al. (1992). Descriptions by Boury-Esnault et al. (1994) and Van Soest et al. (2014) are also similar except that a third category of small anisochelae described in those publications is not present in this specimen (Table 5); however, those specimens were found in more southern latitudes. Trichodragmas are not common, but often 2–3 raphides are seen attached to one another. In situ photos of specimens agree with descriptions by Ackers (1992) of a sulcate, furrowed surface that resembles the “tongue of a sheep”. Discussion. This is the first record of Mycale lingua in Frobisher Bay. The species was collected once from Baffin Bay/Davis Strait by Lundbeck (1905) (70° 24 N, 63° 35 W, 497 m depth), further south on the southern Grand Banks (46° 4.6667 N, 49° 2.5 W, 1267 m depth) by Topsent (1892) and in the Gulf of Saint Lawrence (Brunel et al. 1998), and the Bay of Fundy (Goodwin 2017). The spicules of the Frobisher Bay specimens are slightly smaller than those of separate specimens collected at 631 m (61° 26.417 N, 60° 39.8784 W) and 876 m (67° 58.0382N, 59° 29.0396 W) in Baffin Bay. The styles of these specimens are ~600 µm long and the anisochelae occur in two sizes (~87 µm and ~40 µm long). Ackers (1992) states that the furrowed grooves on the surface of the sponge are highly characteristic, and so despite the slight spicule variations, both specimens are best assigned to M. lingua.Published as part of Dinn, Curtis, Edinger, Evan & Leys, Sally P., 2019, Sponge (Porifera) fauna of Frobisher Bay, Baffin Island, Canada with the description of an Iophon rich sponge garden, pp. 301-325 in Zootaxa 4576 (2) on pages 313-315, DOI: 10.11646/zootaxa.4576.2.5, http://zenodo.org/record/262495
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