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Fig. 2. A in A new deep-water Tethya (Porifera, Tethyida, Tethyidae) from the Great Australian Bight and an updated Tethyida phylogeny
No full textFig. 2. A. Freshly collected specimens (lot SAMA S2096) of Tethya irisae sp. nov. B. Paratype (QM G305000) showing single apical oscule (arrow), and tessellated plate-like polygonal tubercules. C–D. Holotype (SAMA S3387), entire specimen and SEM showing surface tubercules with emerging megascleres. E. Section of UPSZTY 178608, showing the well-developed cortex and cortical canals around the tubercules.Published as part of Sorokin, Shirley J., Ekins, Merrick G., Yang, Qi & Cárdenas, Paco, 2019, A new deep-water Tethya (Porifera, Tethyida, Tethyidae) from the Great Australian Bight and an updated Tethyida phylogeny, pp. 1-26 in European Journal of Taxonomy 529 on page 7, DOI: 10.5852/ejt.2019.529, http://zenodo.org/record/323996
Fig. 3 in A new deep-water Tethya (Porifera, Tethyida, Tethyidae) from the Great Australian Bight and an updated Tethyida phylogeny
No full textFig. 3. Tethya irisae sp. nov. spicules. A–B. Straight style/strongyloxeas. C. Subtylostyle. D. Long-rayed oxyspheraster. E. Short-rayed oxyspheraster with small acanthooxyspheraster. F. Acanthooxyspheraster.Published as part of Sorokin, Shirley J., Ekins, Merrick G., Yang, Qi & Cárdenas, Paco, 2019, A new deep-water Tethya (Porifera, Tethyida, Tethyidae) from the Great Australian Bight and an updated Tethyida phylogeny, pp. 1-26 in European Journal of Taxonomy 529 on page 8, DOI: 10.5852/ejt.2019.529, http://zenodo.org/record/323996
Theonellidae Lendenfeld 1903
No full textFamily Theonellidae Lendenfeld, 1903 Diagnosis (after Pisera and Lévi 2002; Fromont and Pisera, 2011): polymorphic, choanosomal spicules as tetraclone desmas; ectosomal spicules as phyllo- to discotriaenes; large choanosomal oxeas sometimes present; megascleres sometimes completely absent (some Theonella); microscleres characteristically as small, acanthose microrhabds, sometimes centrangulate or with slight curve, sometimes as streptasters and microrhabds (Manihinea) or streptasters only (Racodiscula). Type-genus: Theonella Gray, 1868.Published as part of Hall, Kathryn A., Ekins, Merrick G. & Hooper, John N. A., 2014, Two new desma-less species of Theonella Gray, 1868 (Demospongiae: Astrophorida: Theonellidae), from the Great Barrier Reef, Australia, and a re-evaluation of one species assigned previously to Dercitus Gray, 1867, pp. 451-477 in Zootaxa 3814 (4) on page 455, DOI: 10.11646/zootaxa.3814.4.1, http://zenodo.org/record/491927
Theonella Gray 1868
No full textKey to those species of Theonella Gray, 1868, which lack desmas and other megascleres 1a. Encrusting species, forms thin sheets which cement detritus; desmas absent; megascleres absent; microrhabds very small, ~ 15 µm in length (ranging from 7 to 21 µm)................................................................... 2. 1b. Encrusting species, forms thin sheets which cement detritus; desmas absent; megascleres absent; microrhabds large, conspicuous, ~ 38 µm in length (ranging from 18 to 52 µm).............................................. T. maricae n. sp. 2a. Thin sheets cement exclusively Tenagodus shells into discrete clumps; microrhabds slender, usually curved, sharply hastate at ends, spines conspicuous, long, sharp.......................................................... T. deliqua n. sp. 2b. Thin sheets cement a variety of detritus, including quartz sand, foraminifera, algae and coral fragments; microrhabds robust, generally straight, rounded at ends, spines small, blunt, numerous.... T. xantha (Sutcliffe, Hooper & Pitcher, 2010) n. comb.Published as part of Hall, Kathryn A., Ekins, Merrick G. & Hooper, John N. A., 2014, Two new desma-less species of Theonella Gray, 1868 (Demospongiae: Astrophorida: Theonellidae), from the Great Barrier Reef, Australia, and a re-evaluation of one species assigned previously to Dercitus Gray, 1867, pp. 451-477 in Zootaxa 3814 (4) on page 464, DOI: 10.11646/zootaxa.3814.4.1, http://zenodo.org/record/491927
Theonella maricae Hall & Ekins & Hooper 2014, n. sp.
No full textTheonella maricae n. sp. Figs 1, 4–5 Material examined. Holotype: QM G331427 (=SBD513035), Australia, Great Barrier Reef, inter-reef sea floor, south-east of Guthrie Shoal, 23.095°S 151.875°E, 28.0 m (depth), coll. CSIRO Great Barrier Reef Seabed Biodiversity Project on RV Lady Basten, 22.Sep.2004, epibenthic sled. Description. Based on examination of holotype; specimen post-fixed in ethanol (70%) after initial frozen storage. Growth form and gross morphology: s ponge consists of very thin sheets, thickness ~ 50 µm; sheets encrust over assorted non-specific substrates, cements a variety of unidentified broken gastropod shells, diatoms, broken coral debris into single mass; incorporates large amounts of filamentous algae, quartz sand and debris; holotype in three small ovoid masses, largest mass measures ~ 2 × 2 × 1 cm (total mass dimensions) (Figs 1B, 5A–B). Colour: unknown in life; pale orange to yellow portions of sponge mixed with green algae and dirty cream to brown snail shells, sand and debris when frozen; colour retained in ethanol; stains ethanol pale golden yellow; yellow pigment greasy. Oscules: unobserved macroscopically in frozen and fixed material; also unobserved microscopically. Texture: difficult to determine because of large amounts of debris in sponge mass; sponge soft, fragile, friable, granular, flaccid, limp, highly compressible, slowly resilient, spongy. Surface ornamentation: even, lightly granular. Ectosomal skeleton: indistinguishable from choanosome. Choanosomal skeleton: lax, vague; rigid skeleton entirely absent; skeleton consists only of confused arrangement of interstitial microscleres scattered throughout mesohyl; microscleres sparse in patches, distributed singularly, concentrated in other regions, forming moderately dense carpet; collagen homogenous, slightly granular in appearance; occasional foreign spicules (oxeas, rods from ascidians) incorporated into mesohyl (Figs 5B–C). Megascleres: nil. Microscleres: single category of microrhabd; microrhabds as highly spined microxeas, robust, large, slightly curved, curvature irregular, tapering at ends, tips pointed, shaft covered with numerous, fine, short, conical spines, tips unspined; spines shorter than rhabd width, raised obviously from spicule shaft, arise perpendicular to axis; shaft straight, lacks torsion; dimensions 18.1–51.6 (37.5) × 2.2–4.4 (3.4) µm (Fig 5D). Etymology. This species is named for Mary Kay Harper, College of Pharmacy, University of Utah, who is a close and extensive collaborator on the chemistry of these sponges, and whose painstaking chemical and morphometric observations on theonellids are helping to uncover suites of cryptic species. The chemical complement that Ms Harper has found in specimens of Theonella from the western Pacific may be of taxonomic importance and we honour her contribution to sponge chemotaxonomy in naming this species for her. DNA sequence data. 1 COI barcode sequence was obtained for the holotype (GenBank Accession: KJ494356; see Table 1); this sequence was 709 bp in length (including primers). Ecology and distribution. The single specimen of T. maricae was found in the inter-reef region of the Great Barrier Reef, within the Capricorn Bunker group. Remarks. We have, to date, found only one specimen of T. maricae in our collection. This species is difficult to isolate macroscopically, and it is likely that more specimens remain yet to be identified. Our examination of the holotype specimen shows that, like specimens of T. deliqua, large amounts of foreign sponge and non-sponge debris are incorporated into the structure of T. maricae (Figs 5A–B). Large amounts of filamentous algae, or possibly filamentous bacteria, can be observed within the overall mass of the holotype. Measurements of the microrhabds of the holotype of T. maricae are in one class, with an average length of 37.5 µm and covering a range from 18.1 to 51.6 µm. This range follows a broadly normal distribution (Fig. 4), although it is skewed slightly towards the larger measurements, with the most frequent length approximately reaching 48.0 µm; the 95% confidence interval for the median measurement is 35.9–40.2 µm. Detailed examination of the range of the spicules indicates that although the smallest recorded microrhabd measured 18.1 µm, the majority of the spicules is much larger, with the microrhabs typically exceeding 36 µm in length. Comments. The description of T. maricae adds a second species which does not contain megascleres to Theonella. As with specimens of T. deliqua, the specimen of T. maricae is characterised largely by the absence of any tetractinal or monactinal structural megascleres; both species possess only microrhabds as the native spicule complement. The holotype of T. maricae is distinguished readily, however, from the specimens of T. deliqua by the size and shape of the microscleres. The microrhabds of T. maricae are typically at least twice as large as those of T. deliqua (38 µm v. 15 µm). The spines along the rhabd are small and blunt, measuring less than the width of the shaft; this is in contrast to the long and sharply pointed spines along the microrhabds of T. deliqua. The overall composition of T. maricae incorporates a variety of foreign debris and seafloor rubble, further distinguishing it from T. deliqua, which encrusts almost exclusively over the live and dead shells of a single species of Tenagodus gastropod.Published as part of Hall, Kathryn A., Ekins, Merrick G. & Hooper, John N. A., 2014, Two new desma-less species of Theonella Gray, 1868 (Demospongiae: Astrophorida: Theonellidae), from the Great Barrier Reef, Australia, and a re-evaluation of one species assigned previously to Dercitus Gray, 1867, pp. 451-477 in Zootaxa 3814 (4) on pages 458-461, DOI: 10.11646/zootaxa.3814.4.1, http://zenodo.org/record/491927
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
Theonella deliqua Hall & Ekins & Hooper 2014, n. sp.
No full textTheonella deliqua n. sp. Figs 1–4 Material examined. Holotype: QM G329195 (=SBD520375), Australia, Great Barrier Reef, inter-reef sea floor, south of Wreck Island Reef, 23.775°S 15.005°E, 41.3 m (depth), coll. CSIRO Great Barrier Reef Seabed Biodiversity Project on RV Gwendoline May, 13.Apr.2004, epibenthic sled. Paratype: QM G325567 (=SBD518107), Australia, Great Barrier Reef, inter-reef sea floor, south of Wreck Island Reef, 23.375°S 151.975°E, 43.5 m (depth), coll. CSIRO Great Barrier Reef Seabed Biodiversity Project on RV Gwendoline May, 22.Apr.2004, epibenthic sled. Description. based on examination of holotype and paratype; both specimens post-fixed in ethanol (70%) after initial frozen storage. Growth form and gross morphology: sponge consists of very thin sheets, thickness ~ 50 µm; sheets encrust exclusively over single species of Tenagodus Guettard, 1770 (Gastropoda, Caenogastropoda, Siliquariidae); sponge forms mass with snails, cements Tenagodus shells, incorporates small amounts of algae, detritus and debris; Tenagodus shells in interior of mass appear non-live, shells at perimeter of mass sometimes contain live (at time of fixation) snails; mass incorporates Tenagodus of various ages, some tiny ( 5 mm diameter); holotype mass measures ~ 5 × 7.5 × 3 cm (total mass, including shells) (Figs 1A, 2A–D). Colour: unknown in life; bright orange portions of sponge mixed with green algae and cream snail shells when frozen; colour retained in ethanol; stains ethanol pale golden yellow; yellow pigment greasy. Oscules: unobserved macroscopically in frozen and fixed material; visible microscopically, few, inconspicuous, shallow, discrete, elliptical, ~ 100–200 µm (length), distributed sparsely (Fig 3A). Texture: difficult to determine due to inclusion of large volume of snail shells; sponge very soft, fragile, friable, granular, flaccid, limp, highly compressible, slowly resilient, spongy. Surface ornamentation: even, smooth. Ectosomal skeleton: indistinguishable from choanosome. Choanosomal skeleton: lax, vague; rigid skeleton entirely absent; skeleton consists only of confused arrangement of interstitial microscleres scattered throughout mesohyl; microscleres sparse in patches, distributed singularly, concentrated in other regions, forming dense carpet; collagen homogenous; occasional foreign megascleres (oxeas, regular triacts) incorporated into mesohyl (Figs 2D, 3A–C). Megascleres: nil. Microscleres: single category of microrhabd; microrhabds as highly spined microxeas, small, isodiametric, slender, fine, slightly curved, curvature irregular, tips sharply hastate, rhabd covered with numerous, fine, narrow, conical spines; spines as long or longer than rhabd width, project prominently from spicule shaft, arise perpendicular to axis; shaft straight, lacks torsion; dimensions 7.2–21.6 (14.6) × 2.5–3.4 (3.0) µm (Fig 3D). Etymology. The specific epithet deliqua derives from the Latin deliquus (adjective), meaning lacking or wanting, and refers to the absence of desmas in this species. DNA sequence data. 1 COI barcode sequence was obtained for the holotype (GenBank Accession: KJ494355; see Table 1); this sequence was 709 bp in length (including primers). Ecology and distribution. Specimens of T. deliqua have, to date, been recovered only from the seabed of the inter-reef region of the Great Barrier Reef. Both specimens that we have examined have formed close associations with specimens of a single species of Tenagodus (Siliquariidae). Species of Tenagodus are known to occur only in obligate relationships with sponges (Bieler 2004), although species-specificity (between sponge and snail) of this obligate relationship has not been established (Pansini et al. 1999). Remarks. During examination of the holotype of Theonella deliqua n. sp., a dense mass of regular triactinal spicules (calthrops) was found; many of these calthrops were damaged and had broken rays (Fig 2D). This mass of spicules was found lying in a valley between two Tenagodus shells and incorporated broken oxeas and other spicules (from the Family Didemnidae Giard, 1872 (Class Ascidiacea) and some possibly of holothurian origin). Another similar region, containing an accumulation of monactinal spicules, was found in the broken mouth of an empty Tenagodus shell (Fig 2C). These regions overlie the thin sheets of T. deliqua, but are not incorporated intimately into the mesohyl of the sponge. The localisation of the spicule masses, in conjunction with their varied composition, indicates clearly that they are of foreign origin, and are not innate components. Further, T. deliqua itself encrusts closely over the surface of the Tenagodus shells, cementing only the shells together; detritus and debris appears to amass in rafts at low points where two shells are joined by the sponge. The microrhabds of the holotype and paratype of T. deliqua are of similar proportion, averaging 14.6 µm in length, and spanning a range from 7.1 to 21.6 µm. The range of spicule measurements was normally distributed (Fig. 4), although one spicule was detected which lay outside of this normal range, measuring only 6.7 µm. Although the range of microrhabd length is quite large, the majority of spicules ranges between 12 and 17 µm in length, and this size may be interpreted as “typical” for specimens of T. deliqua. Comments. Specimens of T. deliqua are readily distinguished from the type-species for Theonella, T. swinhoei, (and all other currently known species), by the absence of tetractinal megascleres. No desmas and no triaenes (phyllotrianes nor dichotriaenes) were observed in either specimen of T. deliqua that we examined. The spicule complement of T. deliqua comprises only microrhabds; this condition has not been observed to date in any recorded species of Theonella. Despite the lack of obvious morphological homologies with T. swinhoei and the other members of Theonella, membership of this new species to Theonella can be asserted confidently. The microrhabds of T. deliqua have a similar morphology to those observed in T. swinhoei and other species of Theonella. Although they are not noted directly in the original description by Gray (1868), we have examined material in the QM Porifera collection which is attributed to T. swinhoei, and observed that the microrhabds of T. swinhoei, like those in T. deliqua, are generally straight; although the rhabd may be bent, the central axis is free completely of any torsion, with fine, conical spines projecting perpendicularly from the spicule shaft. The lack of torsion is significant and shared between the microscleres of T. swinhoei and T. deliqua. The straightness of the rods is in contrast to the morphology seen in the streptasters of other astrophorids; this straight morphology justifies our use of the term “microrhabd”, rather than sanidaster or streptaster, to describe these microscleres. Further, and perhaps more significantly, the combination of the corroborating molecular analyses (see below) and the presence of shared chemotaxonomic characters (see below) offers strong support to the attribution of this new species to Theonella.Published as part of Hall, Kathryn A., Ekins, Merrick G. & Hooper, John N. A., 2014, Two new desma-less species of Theonella Gray, 1868 (Demospongiae: Astrophorida: Theonellidae), from the Great Barrier Reef, Australia, and a re-evaluation of one species assigned previously to Dercitus Gray, 1867, pp. 451-477 in Zootaxa 3814 (4) on pages 455-457, DOI: 10.11646/zootaxa.3814.4.1, http://zenodo.org/record/491927
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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