206,615 research outputs found
On a theorem of M. Fujii
No full textIn 1967 M. Fujii [21 computed the KO-i- rings of the complex projective spaces. We give a modified proof here usin
Microzoanthus Fujii & Reimer 2011
No full textGenus <i>Microzoanthus</i> Fujii & Reimer, 2011 <p> Type species. <i>Microzoanthus occultus</i> Fujii & Reimer, 2011, by original designation.</p> <p> <b>Diagnosis.</b> Identical to Microzoanthidae (diagnosis of Fujii & Reimer 2011). Colonial Microzoanthidae free-living and lacking a scleroprotein skeleton. Known from temperate and tropical cryptic habitats in the Pacific Ocean at 0– 23 m. Azooxanthellate. Polyps transparent or faintly red, expand to 3 mm wide and 10 mm long. Capitular ridges largely imperceptible because of heavy encrustations. Oral disk calathiform and edged in a distinct zig-zag pattern (diagnosis expanded using data from Fujii & Reimer 2011). Marginal musculature endodermal, 268–331 Μm in length, composed of 10–16 attachment points. Encrustations of column through ectoderm but not penetrating ectodermal surface of the mesoglea; elliptical lacunae just beneath ectodermal surface of mesoglea form an encircling sinus (diagnosis expanded using data presented here).</p> <p> <b>Remarks.</b> The phylogenetic position of <i>Microzoanthus</i>, as inferred by mitochondrial cytochrome oxidase (COI) and 16s ribosomal (mt 16S rDNA) genes (see Fujii & Reimer 2011; Figs 7 & S1), is near the base of the Zoanthidea and as the sister clade to <i>Isozoanthus</i> (in the COI tree) or all Zoanthidea except <i>Isozoanthus</i> (in the 16S tree). Although these phylogenies are incongruent (with each other and other published hypotheses, <i>e.g.</i>, Sinniger <i>et al.</i> 2005, Swain 2010) and poorly supported (both problems may be resolved by multigene analysis applied to comprehensive taxon sampling), they suggest that <i>Microzoanthus</i> may occupy a critical position near the origin of Zoanthidea and could provide insight into the evolution of <i>Isozoanthus</i> and clarify relationships between the genera of Zoanthidea.</p>Published as part of <i>Swain, Timothy D. & Swain, Laura M., 2014, Molecular parataxonomy as taxon description: examples from recently named Zoanthidea (Cnidaria: Anthozoa) with revision based on serial histology of microanatomy, pp. 81-107 in Zootaxa 3796 (1)</i> on page 99, DOI: 10.11646/zootaxa.3796.1.4, <a href="http://zenodo.org/record/251140">http://zenodo.org/record/251140</a>
Antipathozoanthus hickmani Reimer & Fujii 2010
No full text<i>Antipathozoanthus hickmani</i> Reimer & Fujii, 2010 <p>Figure 3. Morphbank species collection 829705.</p> <p> <b>Material examined.</b> USNM 1134064, paratype.</p> <p> <b>Diagnosis.</b> <i>Antipathozoanthus</i> with endodermal marginal musculature; marginal muscle to 585 Μm in length, composed of as many as 63 unbranched mesogleal pleats. Mesenterial arrangement macrocnemic. Columnar mesoglea adjacent siphonoglyph to 80 Μm width. Occuring at 12–35 m near the Galapagos Islands, symbiotic with <i>Antipathes galapagensis</i> Diechmann, 1941. Coenenchyme, polyps, and tentacles red, yellow, or cream; often contrasting each other. Tentacles and mesenteries to 40, oral disk slightly concave when expanded, capitular ridges to 28. Largest expanded polyps 15 mm long, 12 mm diameter.</p> <p> <b>Description.</b> Colony. Coenenchyme red, yellow, or cream and completely enveloping branches of <i>A. galapagensis</i>; infiltrated with sediment (Reimer & Fujii 2010).</p> <p>Polyp. Capitular ridges conspicuous, 23–28 (Morphbank 830698). Tentacles, oral disk, and column of expanded polyps red, yellow, or cream (Reimer & Fujii 2010). Polyps of diameter 4–12 mm (expanded) extend 4–15 mm from the coenenchyme; body wall infiltrated with sediment (Reimer & Fujii 2010). Tentacles to 40, dicyclic, expand in length greater than diameter of oral disk (Reimer & Fujii 2010).</p> <p>Internal Anatomy. In longitudinal section (Morphbank collection 829723), marginal musculature endodermal with muscle fibers anchored to 30–63 (x = 44, n sections = 10) unbranched mesogleal pleats that decrease in size proximally (Fig. 3A). Fibers enclosed in lacunae in few sections as muscles traverse mesenteries (Fig. 3A). Length of marginal musculature (Fig. 3A) 352–585 Μm (x = 417, n sections= 10); width at widest point (Fig. 3A) 38–109 Μm (x = 79, n sections = 10). Length of largest pleats supporting muscle fibers (Fig. 3A) 26–56 Μm (x = 37, n sections = 10). Scattered lacunae in ectoderm and ectodermal surface of mesoglea are result of dissolved encrustations (Fig. 3B). In region of capitulum (proximal to terminus of marginal musculature; Fig. 3A) ectoderm is 8–40 Μm (x = 21, n sections = 10), mesoglea 26–55 Μm (x = 41, n sections = 10) and endoderm 15–41 Μm (x = 24, n sections = 10) width.</p> <p>In cross section at actinopharynx (Morphbank collection 829707), mesenteries 32, fifth mesenteries macrocnemic (Fig. 3C). Dorsal directives with rounded free border (distal to the mesenterial filament), similar to non-directive imperfect mesenteries (Fig. 3C). Ventral directives (Fig. 3D) supported by mesoglea 199–292 Μm (x = 256, n sections = 10) from column to siphonoglyph, 3–11 Μm (x = 7, n sections = 10) width, 10–21 Μm (x = 17, n sections = 10) width at retractor muscles, and heteromorphic at column 11–24 Μm (x = 15, n sections = 10) width; similar to nondirective perfect mesenteries (Fig. 3D). Actinopharynx deeply furrowed (Fig. 3C). Siphonoglyph distinct and Ushaped (Fig. 3D); ectoderm is 19–38 Μm (x = 27, n sections = 10), mesoglea 14–32 Μm (x = 24, n sections = 10) and endoderm 8–33 Μm (x = 16, n sections = 10) width. Adjacent siphonoglyph (Fig. 3D), column ectoderm is 8–26 Μm (x = 15, n sections = 10), mesoglea 44–80 Μm (x = 60, n sections = 10) and endoderm 23–52 Μm (x = 36, n sections = 10) width. Encircling sinus and mesogleal canals imperceptible, small lacunae resulting from dissolution of encrustations throughout ectoderm and outer quarter width of mesoglea in column (Fig. 3C, D).</p> <p> <b>FIGURE 3</b>. Histology of <i>Antipathozoanthus hickmani</i> (10 Μm sections). Labeled features include actinopharynx (A), column wall (CW), dorsal directives (DD), endodermal marginal musculature (EMM), fifth mesentery (5th), oral disk (OD), siphonoglyph (S), tentacles (T), ventral directives (VD); measurements of capitular tissue width made at black arrow, measurements of column tissue width made at broken arrow, measurements of siphonoglyph tissue width made at gray arrow. <b>A.</b> Longitudinal section of contracted polyp at capitulum showing endodermal marginal musculature. <b>B.</b> Longitudinal section of contracted polyp. <b>C.</b> Cross-section of contracted polyp at level of actinopharynx showing dorsal directives and fifth mesentery. <b>D.</b> Cross-section of contracted polyp at level of actinopharynx showing ventral directives and siphonoglyph.</p> <p>Cnidae. Tentacles and pharynx: basitrichs, mastigophores, holotrichs, spirocysts; filaments: mastigophores, holotrichs; column: holotrichs (see Reimer & Fujii 2010 for size and frequency).</p> <p> <b>Distribution.</b> Associated with <i>A. galapagensis</i> at 12–35 m near Galapagos Islands, Ecuador (Reimer & Fujii 2010).</p> <p> <b>Remarks.</b> <i>Antipathozoanthus hickmani</i> was erected to recognize differences in color (can be red or cream), distribution (Galapagos as opposed to Macaronesia), and host (<i>A. galapagensis</i> as opposed to <i>Tanacetipathes cavernicola</i> Opresko, 2001) from the type species of the genus, <i>A. macaronesicus</i> (Reimer & Fujii 2010).</p>Published as part of <i>Swain, Timothy D. & Swain, Laura M., 2014, Molecular parataxonomy as taxon description: examples from recently named Zoanthidea (Cnidaria: Anthozoa) with revision based on serial histology of microanatomy, pp. 81-107 in Zootaxa 3796 (1)</i> on pages 89-91, DOI: 10.11646/zootaxa.3796.1.4, <a href="http://zenodo.org/record/251140">http://zenodo.org/record/251140</a>
Functional effects of the hadal sea cucumber Elpidia atakama (Echinodermata: Holothuroidea, Elasipodida) reflect small-scale patterns of resource availability
No full textHolothuroidea represent the dominant benthic megafauna in hadal trenches (similar to 6,000-11,000 m), but little is known about their behaviour and functional role at such depths. Using a time-lapse camera at 8,074 m in the Peru-Chile Trench (SE Pacific Ocean), we provide the first in situ observations of locomotory activity for the elasipodid holothurian Elpidia atakama Belyaev in Shirshov Inst Oceanol 92: 326-367, (1971). Time-lapse sequences reveal 'run and mill' behaviour whereby bouts of feeding activity are interspersed by periods of locomotion. Over the total observation period (20 h 25 min), we observed a mean (+/- SD) locomotion speed of 7.0 +/- 5.7 BL h(-1), but this increased to 10.9 +/- 7.2 BL h(-1) during active relocation and reduced to 4.8 +/- 2.9 BL h(-1) during feeding. These observations show E. atakama translocates and processes sediment at rates comparable to shallower species despite extreme hydrostatic pressure and remoteness from surface-derived food
Terrazoanthus sinnigeri Reimer & Fujii 2010
No full text<i>Terrazoanthus sinnigeri</i> Reimer & Fujii, 2010 <p>Figure 6, Table 1. Morphbank species collection 829711.</p> <p> <b>Material examined.</b> USNM 1134067, paratype.</p> <p> <b>FIGURE 6</b>. Histology of <i>Terrazoanthus sinnigeri</i> (10 Μm sections). Labeled features include actinopharynx (A), column wall (CW), dorsal directives (DD), encircling sinus (ES), fifth mesentery (5th), oral disk (OD), siphonoglyph (S), tentacles (T), transitional (mesogleal–endodermal) marginal musculature (TMM), ventral directives (VD); measurements of capitular tissue width made at black arrow, measurements of column tissue width made at broken arrow, measurements of siphonoglyph tissue width made at gray arrow. <b>A.</b> Longitudinal section of contracted polyp at capitulum showing transitional (mesogleal–endodermal) marginal musculature. <b>B.</b> Longitudinal section of contracted polyp. <b>C.</b> Cross-section of contracted polyp at level of actinopharynx showing dorsal directives and fifth mesentery. <b>D.</b> Cross-section of contracted polyp at level of actinopharynx showing ventral directives and siphonoglyph.</p> <p> <b>Diagnosis.</b> Colonial <i>Terrazoanthus</i> with transitional (mesogleal–endodermal) and distinctly curved marginal musculature; marginal muscle to 1021 Μm length, composed of as many as 39 lacunae and 38 mesogleal pleats. Mesenterial arrangement macrocnemic. Columnar mesoglea adjacent siphonoglyph to 141 Μm width. Occurring at 7–27 m near Galapagos Islands, free-living. Coenenchyme and polyps brown or white. Tentacles and mesenteries 30–36, oral disk calathiform when expanded, capitular ridges imperceptible due to extreme encrustations. Largest expanded polyps 10 mm long, 8 mm diameter.</p> <p> <b>Description.</b> Colony. Coenenchyme brown or white and connects polyps as stolons; infiltrated with sediment. Not known associate of other invertebrates. Colonies usually composed of <50 polyps. (Reimer & Fujii 2010).</p> <p>Polyp. Capitular ridges imperceptible (Morphbank 830700). Tentacles and oral disk brown, white, or transparent; column same color as coenenchyme (Reimer & Fujii 2010). Polyps of 2–8 mm in diameter (expanded) rarely extend more than 10 mm from coenenchyme; column wall infiltrated with sediment (Reimer & Fujii 2010). Tentacles 30–36, dicyclic, and expand in length longer than diameter of the calathiform oral disk; (Reimer & Fujii 2010).</p> <p>Internal Anatomy. In longitudinal section (Morphbank collection 829713), marginal musculature mesogleal distally, transitioning through distinct constriction and crescent-curve to endodermal proximally (Fig. 6A). Approximately two-thirds length of marginal muscle enclosed within 25–39 (x = 32, n sections = 10) elliptical or lachrymiform lacunae that occupy full diameter of mesoglea distally, reducing diameter prior to shifting toward endoderm proximally, with half of muscle attachment sites opening to endoderm and forming 23–38 (x = 30, n sections = 10) unbranched mesogleal pleats (Fig. 6A). Length of marginal musculature (Fig. 6A) 808–1021 Μm (x = 903, n sections= 10), width at widest point (Fig. 6A) 114–181 Μm (x = 140, n sections = 10). Diameter of largest lacuna enveloping muscle fibers (Fig. 6A) 84–168 Μm (x = 106, n sections = 10). Large lacunae throughout ectoderm and outer half diameter of mesoglea resulting from dissolution of encrustations (Fig. 6B). In the region of capitulum (proximal to terminus of marginal musculature; Fig. 6A) ectoderm is 27–96 Μm (x = 56, n sections = 10), mesoglea 61–84 Μm (x = 75, n sections = 10) and endoderm is 10–21 Μm (x = 14, n sections = 10) width.</p> <p>In cross section at actinopharynx (Morphbank collection 829712), mesenteries 32, fifth mesenteries macrocnemic (Fig. 6C). Dorsal directives lachrymiform, similar to non-directive imperfect mesenteries (Fig. 6C). Ventral directives (Fig. 6D) supported by mesoglea 94–244 Μm (x = 175, n sections = 5) from column to siphonoglyph, 3–10 Μm (x = 7, n sections = 5) width, at retractor muscles 3–33 Μm (x = 25, n sections = 5) width, and homomorphic at column; similar to non-directive perfect mesenteries (Fig. 6D). Actinopharynx without esophageal furrows (Fig. 6C). Siphonoglyph distinct and U-shaped (Fig. 6D); ectoderm is 15–67 Μm (x = 34, n sections = 5), mesoglea 8–30 Μm (x = 21, n sections = 5), and endoderm 7–27 Μm (x = 17, n sections = 5) width. Adjacent siphonoglyph (Fig. 6D), column ectoderm is 43–94 Μm (x = 63, n sections = 5), mesoglea 62–141 Μm (x = 115, n sections = 5), and endoderm 19–34 Μm (x = 29, n sections = 5) width. Sparse mesogleal canals form an indistinct encircling sinus (Fig. 6C, D). Lacunae resulting from dissolution of encrustations scattered in ectoderm and outer third diameter of mesoglea in column (Fig. 6C, D).</p> <p>Cnidae. Tentacles and pharynx: basitrichs, mastigophores, holitrichs, spirocysts; filaments: mastigophores, holotrichs; column: holotrichs (see Reimer & Fujii 2010 for size and frequency).</p> <p> <b>Distribution.</b> Colonies free-living under rubble at 7–27 m near Galapagos Islands, Ecuador (Reimer & Fujii 2010).</p> <p> <b>Remarks.</b> <i>Terrazoanthus sinnigeri</i> was erected to recognize differences from <i>T. onoi</i> in polyp morphology (smaller oral disk diameter and polyp height), colony size (smaller colonies), color (brown rather than red), microhabitat (cryptic spaces rather than exposed surfaces), cnidae (identity and location), and mutations in nucleotide sequences (Reimer & Fujii 2010). Although the nucleotide sequences (ITS, but not COI or 16S) used in the phylogenetic analyses of Reimer & Fujii (2010) appear to differentiate <i>T. sinnigeri</i> from <i>T. onoi</i> (see Figure 6 of Reimer & Fujii 2010), examination of nucleotide sequences culled from Genbank do not confirm a consistent difference. Nucleotide sequences of the most variable gene (and therefore most likely to detect independently evolving species) commonly used in Zoanthidea phylogenetics (ITS) cannot reliably distinguish between <i>T. sinnigeri</i> and <i>T. onoi or E. patagonichus,</i> and a single nucleotide mutation differentiates <i>E. californicus</i> (Table 1). It is possible that the nucleotide sequences that are identical (or nearly identical) between <i>T. sinnigeri</i> and <i>T. onoi</i> are actually all derived from <i>T. onoi</i> as Genbank accessions EU333803 – EU333810 are labeled <i>T. sinnigeri</i> in Genbank (last accessed on March 14, 2014) and <i>T. onoi</i> in Table 1 of Reimer & Fujii (2010). If the labeling of Table 1 in Reimer & Fujii (2010) is correct, than <i>T. sinnigeri</i> and <i>T. onoi</i> can be distinguished from each other with the use of ITS nucleotide sequences, but <i>T. sinnigeri</i> is differentiated by 5–6 nucleotide mutations from <i>E. californicus</i> (a level of variation in a hypervariable gene that is considered intraspecific in some zoanthid species; <i>e.g.</i>, <i>P. swiftii</i> or <i>Parazoanthus parasiticus</i> (Duchassaing de Fonbressin & Michelotti, 1860): Swain 2009b). Out of these species, <i>T. sinnigeri</i> and <i>E. californicus</i> appear to be the most morphologically similar with many features indistinguishable (<i>e.g.</i>, tentacle count and marginal muscle form) between the two species except for several characters that assess polyp size (<i>e.g.</i>, the tissue thicknesses and marginal muscle dimensions) of the <i>T. sinnigeri</i> paratype are 60–140% of those of <i>E. patagonichus</i> specimens used in Swain (2010). It is unclear if these differences are sufficient to differentiate species or if the apparent differences between specimens would withstand broader sampling.</p>Published as part of <i>Swain, Timothy D. & Swain, Laura M., 2014, Molecular parataxonomy as taxon description: examples from recently named Zoanthidea (Cnidaria: Anthozoa) with revision based on serial histology of microanatomy, pp. 81-107 in Zootaxa 3796 (1)</i> on pages 96-98, DOI: 10.11646/zootaxa.3796.1.4, <a href="http://zenodo.org/record/251140">http://zenodo.org/record/251140</a>
Parazoanthus darwini Reimer & Fujii 2010
No full textParazoanthus darwini Reimer & Fujii, 2010 Figure 4. Morphbank species collection 830697. Material examined. USNM 1134065, paratype. Diagnosis. Colonial Parazoanthus with endodermal marginal musculature; marginal muscle to 529 Μm in length, composed of as many as 27 mesogleal pleats. Mesenterial arrangement macrocnemic. Columnar mesoglea adjacent siphonoglyph to 357 Μm width. Occurring at 2–30 m near the Galapagos Islands, symbiotic with Poecilosclerida and Hadromerida. Coenenchyme and polyps tan, pink, or cream. Tentacles and mesenteries 24–30, oral disk concave when expanded, capitular ridges inconspicuous. Largest expanded polyps 6 mm long, 6 mm diameter. Description. Colony. Coenenchyme light tan, light pink, or cream-colored and covering portions of the surface of sponge hosts with meandering bands and sheets; infiltrated with sediment (Reimer & Fujii 2010). Facultative symbionts of Demospongiae of orders Poecilosclerida and Hadromerida (Reimer & Fujii 2010). Independent of sponge hosts, colonies can cover areas of 0.02 to> 1 m 2 (Reimer & Fujii 2010). Polyp. Capitular ridges inconspicuous (Morphbank 830699). Tentacles yellow, orange, or cream; oral disk red or yellow; column same color as coenenchyme (Reimer & Fujii 2010). Polyps of diameter 3–6 mm (expanded) extend 2–6 mm from the coenenchyme and retract nearly flush with surface of the coenenchyme; body wall infiltrated with sediment (Reimer & Fujii 2010). Tentacles 24–30, dicyclic, and expand in length greater than diameter of oral disk (Reimer & Fujii 2010). FIGURE 4. Histology of Parazoanthus darwini (10 Μm sections). Labeled features include actinopharynx (A), column wall (CW), dorsal directives (DD), endodermal marginal musculature (EMM), encircling sinus (ES), fifth mesentery (5 th), oral disk (OD), peristome (P), siphonoglyph (S), tentacles (T), ventral directives (VD); measurements of capitular tissue width made at black arrow, measurements of column tissue width made at broken arrow, measurements of siphonoglyph tissue width made at gray arrow. A. Longitudinal section of contracted polyp at capitulum showing endodermal marginal musculature. B. Longitudinal section of contracted polyp. C. Cross-section of contracted polyp at level of actinopharynx showing dorsal directives and fifth mesentery. D. Cross-section of contracted polyp at level of actinopharynx showing ventral directives and siphonoglyph. Internal Anatomy. In longitudinal section (Morphbank collection 829710), marginal musculature endodermal with muscle fibers anchored to 14–27 (x = 20, n sections = 10) unbranched mesogleal pleats that decrease in size proximally (Fig. 4 A). Fibers enclosed in lacunae in few sections as muscles transverse mesenteries. Length of marginal musculature (Fig. 4 A) 403–529 Μm (x = 480, n sections= 10); width at widest point (Fig. 4 A) 67–84 Μm (x = 76, n sections = 10). Length of largest pleats supporting muscle fibers (Fig. 4 A) 41–57 Μm (x = 51, n sections = 10). Copious large lacunae throughout ectoderm and outer three-quarters diameter of mesoglea resulting from dissolution of encrustations (Fig. 4 B). In the region of capitulum (proximal to terminus of marginal musculature; Fig. 4 A) ectoderm is 42–119 Μm (x = 78, n sections = 10), mesoglea 95–258 Μm (x = 162, n sections = 10) and endoderm 13–28 Μm (x = 19, n sections = 10) width. In cross section at actinopharynx (Morphbank collection 829709), mesenteries 20, fifth mesenteries macrocnemic (Fig. 4 C). Dorsal directives with bulbous free border (distal to the mesenterial filament), similar to non-directive imperfect mesenteries (Fig. 4 C). Ventral directives (Fig. 4 D) supported by mesoglea 189–218 Μm (x = 196, n sections = 7) from column to siphonoglyph, 4–6 Μm (x = 5, n sections = 7) width, same at retractor muscles, and heteromorphic at column 10–14 Μm (x = 12, n sections = 7) width; similar to non-directive perfect mesenteries (Fig. 4 D). Actinopharynx without esophageal furrows (Fig. 4 C). Siphonoglyph distinct and V-shaped (Fig. 4 D); ectoderm is 13–20 Μm (x = 17, n sections = 7), mesoglea 8–24 Μm (x = 12, n sections = 7), and endoderm 56–155 Μm (x = 82, n sections = 7) width. Adjacent siphonoglyph (Fig. 4 D), column ectoderm is 76–165 Μm (x = 115, n sections = 8), mesoglea 222–357 Μm (x = 280, n sections = 8), and endoderm 15–28 Μm (x = 20, n sections = 8) width. Encircling sinus composed of oval and flattened lacunae just beneath the endodermal surface of the mesoglea (Fig. 4 C, D). Large lacunae resulting from dissolution of encrustations throughout ectoderm and outer four-fifths width of mesoglea in column (Fig. 4 C, D). Cnidae. Tentacles and pharynx: basitrichs, mastigophores, holotrichs, spirocysts; filaments: mastigophores, holotrichs; column: holotrichs (see Reimer & Fujii 2010 for size and frequency). Distribution. Facultatively associated with Demospongiae of orders Poecilosclerida and Hadromerida at 2–30 m near Galapagos Islands, Ecuador (Reimer & Fujii 2010). Remarks. With notable similarity in genetics (Swain 2010), morphology, intimacy with host sponge (sensu Swain & Wulff 2007), and specificity to Poecilosclerida and Hadromerida; Pacific members of P. darwini could easily be mistaken for Caribbean Parazoanthus swiftii (Duchassaing de Fonbressin & Michelotti, 1860) if the distributions overlapped. Of named Parazoanthus with available nucleotide sequences, no species are more closely related (Swain 2010). Parazoanthus darwini was erected (in part) to recognize differences from P. swiftii in polyp morphology (larger polyps with greater numbers of tentacles and mesenteries), obligation to host (commonly observed without its sponge host), and distribution (Reimer & Fujii 2010).Published as part of Swain, Timothy D. & Swain, Laura M., 2014, Molecular parataxonomy as taxon description: examples from recently named Zoanthidea (Cnidaria: Anthozoa) with revision based on serial histology of microanatomy, pp. 81-107 in Zootaxa 3796 (1) on pages 91-93, DOI: 10.11646/zootaxa.3796.1.4, http://zenodo.org/record/25114
Microzoanthus kagerou Fujii & Reimer 2011
No full textMicrozoanthus kagerou Fujii & Reimer, 2011 Figure 7, 8. Morphbank species collection 829717. Material examined. USNM 1150463, paratype. Diagnosis. Colonial Microzoanthus with endodermal marginal musculature; marginal muscle to 331 Μm length, composed of as many as 16 mesoglea pleats. Mesenterial arrangement macrocnemic. Columnar mesoglea adjacent siphonoglyph to 21 Μm width. Occurring at 1–20 m throughout the temperate and tropical Pacific Ocean, free-living, and lacking scleroprotein skeleton. Coenenchyme and polyps transparent or faintly red. Tentacles and mesenteries 20–26, oral disk may have fluorescent green pigments and is calathiform when expanded, capitular ridges 10–13 when discernible. Largest expanded polyps 10 mm long, 3 mm diameter. FIGURE 7. Histology of Microzoanthus kagerou (10 Μm sections). Labeled features include actinopharynx (A), column wall (CW), dorsal directives (DD), endodermal marginal musculature (EMM), encircling sinus (ES), fifth mesentery (5 th), oral disk (OD), peristome (P), siphonoglyph (S), tentacles (T), ventral directives (VD); measurements of capitular tissue width made at black arrow, measurements of column tissue width made at broken arrow, measurements of siphonoglyph tissue width made at gray arrow. A. Longitudinal section of contracted polyp at capitulum showing endodermal marginal musculature. B. Longitudinal section of contracted polyp. C. Cross-section of contracted polyp at level of actinopharynx showing dorsal directives and fifth mesenteries. D. Cross-section of contracted polyp at level of actinopharynx showing ventral directives and siphonoglyph. Description. Colony. Coenenchyme transparent or faintly red and connects polyps (often> 1 cm apart) as a narrow stolon; infiltrated with sediment. Not known to associate with other invertebrates (Fujii & Reimer 2011). Polyp. Capitular ridges largely imperceptible (Morphbank 830702), 10–13 when observable (Fujii & Reimer 2011). Tentacles and column transparent or faintly red; oral disk same color (but can have fluorescent green pigments) and is distinctly calathiform as margin extends above oral disk greater than one-fourth its diameter (Fujii & Reimer 2011). Polyps to 3 mm in diameter (expanded) extend to 10 mm from coenenchyme; column wall infiltrated with sediment. Tentacles 20–26, dicyclic, and expand in length to 2–3 times diameter of column (Fujii & Reimer 2011). Internal Anatomy. In longitudinal section (Morphbank collection 829719), marginal musculature endodermal, muscle fibers anchored to 10–16 (x = 13, n sections = 31) unbranched mesogleal pleats (Fig. 7 A). Mesogleal pleats decrease in size proximally. Fibers enclosed in lacunae in few sections as muscles transverse mesenteries (Fig. 7 A, 8). Length of marginal musculature (Fig. 7 A) 268–331 Μm (x = 298, n sections= 10), width at widest point (Fig. 7 A) 34–65 Μm (x = 52, n sections = 10). Length of largest mesogleal pleats supporting the muscle fibers (Fig. 7 A) 15–36 Μm (x = 27, n sections = 10). Large lacunae resulting from dissolution of encrustations throughout capitular ectoderm which occasionally distort ectodermal surface of mesoglea (Fig. 7 B). In the region of capitulum (proximal to terminus of marginal musculature; Fig. 7 A) ectoderm is 6–22 Μm (x = 12, n sections = 10), mesoglea 7–16 Μm (x = 11, n sections = 10) and endoderm 8–15 Μm (x = 12, n sections = 10) width. In cross section at actinopharynx (Morphbank collection 829718), mesenteries 22, fifth mesenteries macrocnemic (Fig. 7 C). Dorsal directives with slight flair of mesoglea at the free border, similar to non-directive imperfect mesenteries (Fig. 7 C). Ventral directives (Fig. 7 C, D) supported by mesoglea 105–164 Μm (x = 134, n sections = 10) from column to siphonoglyph, 2–4 Μm (x = 3, n sections = 10) width, at retractor muscles 6–15 Μm (x = 11, n sections = 10) width, and homomorphic at column; similar to non-directive perfect mesenteries (Fig. 7 C, D). Actinopharynx without esophageal furrows (Fig. 7 C, D). Siphonoglyph distinct and U-shaped (Fig. 7 D); ectoderm is 33–88 Μm (x = 46, n sections = 10), mesoglea 4–8 Μm (x = 6, n sections = 10), and endoderm 6–10 Μm (x = 8, n sections = 10) width. Adjacent siphonoglyph (Fig. 7 D), column ectoderm is 9–45 Μm (x = 27, n sections = 10), mesoglea 11–21 Μm (x = 14, n sections = 10), and endoderm 10–14 Μm (x = 12, n sections = 10) width. Elliptical lacunae form an encircling sinus just beneath ectodermal surface of mesoglea (Fig. 7 D). Large lacunae resulting from dissolution of encrustations throughout columnar ectoderm, which occasionally distort ectodermal surface of mesoglea (Fig. 7 C, D). Cnidae. Tentacles and pharynx: basitrichs, holotrichs, spirocysts; filament: basitrichs, mastigophores, holotrichs, spirocysts; column: holotrichs (see Table 1 of Fujii & Reimer 2011 for size and frequency). Distribution. Colonies free-living under rubble and interstices at 1–20 m throughout the temperate and tropical Pacific Ocean (Fujii & Reimer 2011). Remarks. Microzoanthus kagerou differs from Microzoanthus occultus Fujii & Reimer, 2011 in colony morphology (M. kagerou has larger colonies whose polyps are connected by well-developed stolons), cnidae (microbasic p-mastigophores are absent from the actinopharynx of M. kagerou), and nucleotide (COI, 16 S rDNA, and ITS rDNA gene) sequences (Fujii & Reimer 2011). The original description of M. kagerou included traditional (higher-taxon defining) morphological features in addition to cnidae and nucleotide sequences, but our observations of the paratypes are not entirely consistent with those of the original authors. We concur with Fuji and Reimer (2011; see Fig 6 C) on the number of marginal muscle-attachment points (16) and the lack of mesogleal encrustations. We differ from Fuji & Reimer (2011) in their interpretation of the marginal musculature as being transitional from mesogleal to endodermal, whereas we interpret it as endodermal musculature that is sporadically and partially enclosed in lacunae as muscles traverse mesenteries (Fig 8). Of the 31 serial sections we examined, 9 sections (not in a series) are completely endodermal (pleats only), 2 have attachment sites composed of more than half lacunae, and most (21) have small portions of sites enclosed in lacunae (Fig. 8). The location of these lacunae appear to be randomly distributed and are observed in proximal, central, and distal portions of the marginal muscle, a situation inconsistent with the interpretation of a transitional musculature. Furthermore, Fujii & Reimer (2011) describe mesoglea in an unspecified region of the polyp as “approximately 90 Μm and show histology with mesoglea that approximates that width at the capitulum (judging by the scale bar in Fig. 6 B of Fujii & Reimer 2011) while measurements from histology reported here do not exceed 21 Μm (65 Μm if pleats of marginal musculature are included). We consider the discrepancies in measurements to expand the circumscription of morphological variation of M. kagerou.Published as part of Swain, Timothy D. & Swain, Laura M., 2014, Molecular parataxonomy as taxon description: examples from recently named Zoanthidea (Cnidaria: Anthozoa) with revision based on serial histology of microanatomy, pp. 81-107 in Zootaxa 3796 (1) on pages 99-102, DOI: 10.11646/zootaxa.3796.1.4, http://zenodo.org/record/25114
Terrazoanthus onoi Reimer & Fujii 2010
No full textTerrazoanthus onoi Reimer & Fujii, 2010 Figure 5, Table 1. Morphbank species collection 829714. Material examined. USNM 1134066, paratype. Diagnosis. Colonial Terrazoanthus with transitional (mesogleal–endodermal) and distinctly curved marginal musculature; marginal muscle to 922 Μm in length, composed of as many as 31 lacunae and 31 mesogleal pleats. Mesenterial arrangement macrocnemic. Columnar mesoglea adjacent siphonoglyph to 126 Μm width. Occurring at 1–35 m near Galapagos Islands, free-living. Coenenchyme and polyps colored reds or browns. Tentacles and mesenteries 32–40, oral disk calathiform when expanded, capitular ridges imperceptible due to extreme encrustations. Largest expanded polyps 20 mm long, 12 mm diameter. Description. Colony. Coenenchyme tan to dark brown and covers substratum as sheets; infiltrated with sediment. Not known to associate with other invertebrates. Colonies can cover areas> 1 m 2 (Reimer & Fujii 2010). Polyp. Capitular ridges inconspicuous (Morphbank 830701). Tentacles and oral disk bright red or red-brown; column and coenenchyme same color (Reimer & Fujii 2010). Polyps of 4–12 mm in diameter (expanded) rarely extend more than 20 mm from coenenchyme and cannot retract flush; body wall infiltrated with sediment (Reimer & Fujii 2010). Tentacles 32–40, dicyclic, and expand in length nearly the diameter of the calathiform oral disk (Reimer & Fujii 2010). FIGURE 5. Histology of Terrazoanthus onoi (10 Μm sections). Labeled features include actinopharynx (A), column wall (CW), dorsal directives (DD), encircling sinus (ES), fifth mesentery (5 th), oral disk (OD), peristome (P), siphonoglyph (S), tentacles (T), transitional (mesogleal–endodermal) marginal musculature (TMM), ventral directives (VD); measurements of capitular tissue width made at black arrow, measurements of column tissue width made at broken arrow, measurements of siphonoglyph tissue width made at gray arrow. A. Longitudinal section of contracted polyp at capitulum showing transitional (mesogleal–endodermal) marginal musculature. B. Longitudinal section of contracted polyp. C. Cross-section of contracted polyp at level of actinopharynx showing dorsal directives and fifth mesenteries. D. Cross-section of contracted polyp at level of actinopharynx showing ventral directives and siphonoglyph. Internal Anatomy. In longitudinal section (Morphbank collection 829716), marginal musculature mesogleal distally, transitioning through distinct constriction and crescent-curve to endodermal proximally (Fig. 5 A). Approximately two-thirds length of marginal muscle enclosed within 25–31 (x = 28, n sections = 10) elliptical or lachrymiform lacunae that occupy full diameter of mesoglea distally, reducing in diameter prior to shifting toward endoderm proximally, with half of muscle attachment sites opening to endoderm and forming 22–31 (x = 27, n sections = 10) unbranched mesogleal pleats (Fig. 5 A). Length of marginal musculature (Fig. 5 A) 756–922 Μm (x = 858, n sections= 10), width at widest point (Fig. 5 A) 116–135 Μm (x = 124, n sections = 10). Diameter of largest lacuna enveloping muscle fibers (Fig. 5 A) 86–103 Μm (x = 94, n sections = 10). Large lacunae throughout ectoderm and outer three-quarters diameter of mesoglea resulting from dissolution of encrustations (Fig. 5 B). In the region of capitulum (proximal to terminus of marginal musculature; Fig. 5 A), ectoderm is 5–51 Μm (x = 24, n sections = 10), mesoglea 50–99 Μm (x = 72, n sections = 10) and endoderm 6–23 Μm (x = 11, n sections = 10) width. In cross section at actinopharynx (Morphbank collection 829715), mesenteries 30, fifth mesenteries macrocnemic (Fig. 5 C). Dorsal directives lachrymiform, similar to non-directive imperfect mesenteries (Fig. 5 C). Ventral directives (Fig. 5 D) supported by mesoglea 140–191 Μm (x = 166, n sections = 10) from column to siphonoglyph, 4–11 Μm (x = 8, n sections = 10) width, at retractor muscles 21–28 Μm (x = 24, n sections = 10) width, and homomorphic at column; similar to non-directive perfect mesenteries (Fig. 5 D). Actinopharynx without esophageal furrows (Fig. 5 C). Siphonoglyph distinct and U-shaped (Fig. 5 D); ectoderm is 23–62 Μm (x = 37, n sections = 10), mesoglea 15–28 Μm (x = 22, n sections = 10), and endoderm 7–16 Μm (x = 12, n sections = 10) width. Adjacent siphonoglyph (Fig. 5 D), column ectoderm is 23–55 Μm (x = 44, n sections = 10), mesoglea 96–126 Μm (x = 109, n sections = 10), and endoderm 17–23 Μm (x = 20, n sections = 10) width. Sparse mesogleal canals form an indistinct encircling sinus (Fig. 5 C, D). Lacunae resulting from dissolution of encrustations scattered in ectoderm and outer half width of mesoglea in column (Fig. 5 C, D). Cnidae. Tentacles, pharynx, and filament: basitrichs, mastigophores, holotrichs, spirocyst; column: holotrichs (see Reimer & Fujii 2010 for size and frequency). Distribution. Colonies free-living at 1–35 m near Galapagos Islands, Ecuador (Reimer & Fujii 2010). Remarks. Terrazoanthus onoi was erected to recognize differences from T. sinnigeri in polyp morphology (larger oral disk diameter and polyp height), colony size (larger colonies), color (red rather than brown), microhabitat (exposed surfaces rather than cryptic spaces), cnidae (identity and location), and mutations in nucleotide sequences (Reimer & Fujii 2010). Although the nucleotide sequences (ITS, but not COI or 16 S) used in the phylogenetic analyses of Reimer & Fujii (2010) appear to differentiate T. onoi from T. sinnigeri (see Figure 6 of Reimer & Fujii 2010), examination of nucleotide sequences culled from Genbank do not confirm a consistent difference. Nucleotide sequences of the most variable gene (and therefore most likely to detect independently evolving species) commonly used in Zoanthidea phylogenetics (ITS) cannot reliably distinguish between T. onoi and T. sinnigeri or E. patagonichus, and a single nucleotide mutation differentiates E. californicus (Table 1). It is possible that the nucleotide sequences that are identical (or nearly identical) between T. onoi and T. sinnigeri are actually all derived from T. onoi as Genbank accessions EU 333803 – EU 333810 are labeled T. sinnigeri in Genbank (last accessed on March 14, 2014) and T. onoi in Table 1 of Reimer & Fujii (2010). If the labeling of Table 1 in Reimer & Fujii (2010) is correct, than T. onoi and T. sinnigeri can be distinguished from each other with the use of ITS nucleotide sequences, but not T. onoi from E. patagonichus. Out of these species, T. onoi and E. patagonichus appear to be the most morphologically (and genetically) similar with many features indistinguishable (e.g., tentacle count and marginal muscle form) between the two species except for several characters that assess polyp size (e.g., the tissue thicknesses and marginal muscle dimensions) of the T. onoi paratype are 60–80 % of those of E. patagonichus specimens used in Swain (2010). It is unclear if these differences are sufficient to differentiate species or if the apparent differences between specimens would withstand broader sampling.Published as part of Swain, Timothy D. & Swain, Laura M., 2014, Molecular parataxonomy as taxon description: examples from recently named Zoanthidea (Cnidaria: Anthozoa) with revision based on serial histology of microanatomy, pp. 81-107 in Zootaxa 3796 (1) on pages 94-96, DOI: 10.11646/zootaxa.3796.1.4, http://zenodo.org/record/25114
Microzoanthidae Fujii & Reimer 2011
No full textFamily Microzoanthidae Fujii & Reimer, 2011 <p>Zoanthidea with macrocnemic mesenterial arrangement and simple endodermal marginal musculature. Species are free-living and are found attached cryptically under rubble or interstices throughout temperate and tropical Pacific. Azooxanthellate. Microzoanthidae share specific genetic characters (of the mitochondrial COI and 16S rDNA genes) and are differentiated from other Zoanthidea by encrustations that penetrate to the ectodermal surface of the mesoglea, but not into the mesoglea itself. Expanded polyps to 3 mm diameter and 10 mm length, encrusted, and connected by coenenchyme stolons. Oral disk calathiform and margin ornamented with distinct zig-zag pattern. Tentacles 20–26, 6– 9 mm long (diagnosis expanded from Fujii & Reimer 2011).</p>Published as part of <i>Swain, Timothy D. & Swain, Laura M., 2014, Molecular parataxonomy as taxon description: examples from recently named Zoanthidea (Cnidaria: Anthozoa) with revision based on serial histology of microanatomy, pp. 81-107 in Zootaxa 3796 (1)</i> on page 99, DOI: 10.11646/zootaxa.3796.1.4, <a href="http://zenodo.org/record/251140">http://zenodo.org/record/251140</a>
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