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All eight extant species ofRhabdopleuradescribed between 1869 and 2018 are provisionally accepted as valid based on a review of the literature and new data on two little-known species from the Azores. Additionally, four new species are described from the New Zealand region, increasing global diversity by 50%, and a dichotomous key to all 12 described species is provided based on morphological criteria. The distinction between colony morphologies based on erect-tube inception is regarded as particularly helpful in initial characterization of species. Erect ringed tubes are either produced directly from the surface of creeping-tubes or indirectly, i.e. a short adherent side branch from a creeping tube is interpolated between the creeping tube and an erect tube; such side branches are blind-ending. These two modes of erect-tube origination are here respectively termeddirectandindirect. Species with indirect erect-tube budding are predominant in the North Atlantic whereas species with direct erect-tube budding dominate in New Zealand waters. The only indirect-erect species from New Zealand, Rhabdopleura chathamica n. sp., was discovered on deepwater coral from 10081075 m, constituting the deepest record of the genus to date. Rhabdopleura emancipata n. sp., collected only in a detached state, constitutes a three-dimensional tangled growth that grew freely into the water columna unique morphology hitherto unknown among extant species. Owing to this growth mode, it provided a substratum for epibionts from several phyla. Rhabdopleura francesca n. sp. and Rhabdopleura decipula n. sp. are morphologically very similar but are distinguishable by their distinct placements in a phylogeny based on 16S mitochondrial and 18S nuclear rRNA genes. Phylogenetic reconstructions based on rRNA and mitochondrial genome data contribute to an updated phylogeny of all Rhabdopleura species sequenced thus far, some of which require more molecular sequences and morphological analyses for taxonomic determination.
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Mitocondrias , Animales , Filogenia , Nueva Zelanda , ARN Ribosómico 18S/genética , Secuencia de Bases , Mitocondrias/genéticaRESUMEN
Pachyzoidae is a little-known family of deep-sea ctenostome Bryozoa that until now was monospecific for Pachyzoon atlanticum. Originally described from the Atlantic Ocean, the genus was also found off southeastern New Caledonia in deep waters of the geological continent of Zealandia. Pachyzoon atlanticum forms globular to flat round colonies, living on soft, muddy to sandy bottoms with a few rhizoidal cystid appendages extending from the basal, substrate-oriented side. In this study, we investigate additional pachyzoids, collected between 1965 and 2015 from over 40 sites around New Zealand, by means of detailed morphological and histological investigations. In total, several hundred colonies were encountered in the NIWA Invertebrate Collection, comprising two new species of the genus Pachyzoon, P. grischenkoi sp. nov. and P. pulvinaris sp. nov., and the new genus and species Jeanloupia zealandica gen. et sp. nov.. The genus Jeanloupia is characterized by small disc-shaped colonies with highly elongated peristomes and a quadrangular aperture, distinct from the round apertures of the genus Pachyzoon. Pachyzoid species differ in colony structure and shape, apertural papillae and polypide features such as tentacle number or digestive-tract details. Cystid appendages are non-kenozooidal, but may originate from laterally flanking kenozooids. Based on published images, alleged P. atlanticum from New Caledonia is re-interpreted as P. pulvinaris n. sp.. Morphological characters support alcyonidioidean relationships, as previously suggested. First observations on pachyzoid reproduction show macrolecithal oocytes and brooding of embryos, which seems to be the general pattern for this family. The occurrence of three new Zealandian species in a comparatively small geographical area far from the Atlantic indicates a high possibility of more species to discovered.
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Parental care is considered crucial for the enhanced survival of offspring and evolutionary success of many metazoan groups. Most bryozoans incubate their young in brood chambers or intracoelomically. Based on the drastic morphological differences in incubation chambers across members of the order Cheilostomatida (class Gymnolaemata), multiple origins of incubation were predicted in this group. This hypothesis was tested by constructing a molecular phylogeny based on mitogenome data and nuclear rRNA genes 18S and 28S with the most complete sampling of taxa with various incubation devices to date. Ancestral character estimation suggested that distinct types of brood chambers evolved at least 10 times in Cheilostomatida. In Eucratea loricata and Aetea spp. brooding evolved unambiguously from a zygote-spawning ancestral state, as it probably did in Tendra zostericola, Neocheilostomata, and 'Carbasea' indivisa. In two further instances, brooders with different incubation chamber types, skeletal and non-skeletal, formed clades (Scruparia spp., Leiosalpinx australis) and (Catenicula corbulifera (Steginoporella spp. (Labioporella spp., Thalamoporella californica))), each also probably evolved from a zygote-spawning ancestral state. The modular nature of bryozoans probably contributed to the evolution of such a diverse array of embryonic incubation chambers, which included complex constructions made of polymorphic heterozooids, and maternal zooidal invaginations and outgrowths.
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Briozoos , Invertebrados , Animales , Filogenia , Reproducción/genéticaRESUMEN
Ctenostome bryozoans are unmineralized and mostly marine. Their lack of calcified skeletal features requires other characters to be considered for systematic and phylogenetic considerations. As a continuation of an ongoing series of studies, we herein investigate the morphology of Amphibiobeania epiphylla, a unique bryozoan inhabiting mangrove leaves that are highly exposed to tidal cycles and regular dry events according to the tidal cycle. Besides this interesting mode of life, the species was originally interpreted to be a weakly mineralized cheilostome bryozoan, whereas molecular data place it among ctenostome bryozoans. To elucidate the systematic and phylogenetic position of the genus and also find morphological adaptations to an extreme habitat, we investigated the morphology of A. epiphylla in detail. Zooids show a lophophore with eight tentacles and a simple gut with a prominent caecum, lophophoral anus and most notably a distinct gizzard in the cardiac region. Gizzard teeth are multiple, simple homogeneous cuticular structures. The cuticle of the zooid is rather uniform and shows no respective thickenings into opercular flaps or folds. Likewise, apertural muscles are represented by a single pair of muscles. There are no specific closing muscles in the apertural area like the operculum occlusors of cheilostomes. Most prominent within zooids is a spongiose tissue filling most of the body cavity. Although not properly understood, this tissue may aid in keeping animals moist and hydrated during prolonged dry times. In summary, all morphological characters support a ctenostome rather than a cheilostome affinity, possibly with Vesicularioidea or Victorelloidea. In addition, we provide new molecular data that clearly supports such a closer relationship.
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Briozoos , Animales , Filogenia , Briozoos/anatomía & histología , Ecosistema , Canal Anal , MúsculosRESUMEN
Twenty-four Recent species of the boreal-Arctic and Pacific cheilostome bryozoan genus Rhamphostomella are described. The species R. tatarica and R. pacifica are transferred to Rhamphostomella from Posterula and Porella, respectively. Eight species are new: R. aleutica n. sp., R. aspera n. sp., R. commandorica n. sp., R. echinata n. sp., R. microavicularia n. sp., R. morozovi n. sp., R. multirostrata n. sp. and R. obliqua n. sp. Neotypes are selected for six species, and lectotypes for eight species. Mixtoscutella n. gen. is established for several Rhamphostomella-like species, including M. androsovae [formerly Smittina androsovae Gontar], M. cancellata [formerly Escharella porifera forma cancellata Smitt], M. harmsworthi [formerly Schizoporella harmsworthi Waters], M. ovata [formerly Cellepora ovata (Smitt)], and M. ussowi [formerly Schizoporella ussowi (Kluge)]. In addition to taxonomic revision, the morphology (frontal shields, ovicells and multiporous septula), ecology and zoogeography of these cheilostomes are discussed, and identification keys are presented. Most species of Rhamphostomella have broad bathymetric distributions. Some have long protuberances on their basal walls that allow them to grow elevated above allelopathically active substrates such as sponges. The diversity of Rhamphostomella peaks in the northwestern Pacific.
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Briozoos , AnimalesRESUMEN
Ctenostome bryozoans are a small group of gymnolaemates that comprise only a few hundred described species. Soft-tissue morphology remains the most important source for analysing morphological characters and inferring relationships within this clade. The current study focuses on the genus Sundanella, for which morphological data is scarce to almost absent. We studied two species of the genus, including one new to science, using histology and three-dimensional reconstruction techniques and confocal laser scanning microscopy. Sundanella generally has a thick, sometimes arborescent cuticle and multiporous interzooidal pore plates. The lophophore is bilateral with an oral rejection tract and generally has 30 or 31 tentacles in both species. The digestive tract shows a large cardia in S. floridensis sp. nov. and an extremely elongated intestine in Sundanella sibogae. Both terminate via a vestibular anus. Only parietodiaphragmatic muscles are present and four to six duplicature bands. Both species show a large broad frontal duplicature band further splitting into four individual bands. The collar is vestibular. Sundanella sibogae shows highly vacuolated cells at the diaphragm, whereas S. floridensis sp. nov. has unique glandular pouches at the diaphragmal area of the tentacle sheath. Such apertural glands have never been encountered in other ctenostomes. Both species of Sundanella are brooders that brood embryos either in the vestibular or cystid wall. Taken together, the current analysis shows numerous characteristics that refute an assignment of Sundanella to victorellid ctenostomes, which only show superficial resemblance, but differ substantially in most of their soft-body morphological traits. Instead, a close relationship with other multiporate ctenostomes is evident and the families Pherusellidae, Flustrellidrae and Sundanellidae should be summarized as clade 'Multiporata' in the future.
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Briozoos , Canal Anal , Animales , Briozoos/anatomía & histología , Tracto Gastrointestinal , Microscopía Confocal , Músculos/anatomía & histologíaRESUMEN
Phylogenetic relationships and the timing of evolutionary events are essential for understanding evolution on longer time scales. Cheilostome bryozoans are a group of ubiquitous, species-rich, marine colonial organisms with an excellent fossil record but lack phylogenetic relationships inferred from molecular data. We present genome-skimmed data for 395 cheilostomes and combine these with 315 published sequences to infer relationships and the timing of key events among c. 500 cheilostome species. We find that named cheilostome genera and species are phylogenetically coherent, rendering fossil or contemporary specimens readily delimited using only skeletal morphology. Our phylogeny shows that parental care in the form of brooding evolved several times independently but was never lost in cheilostomes. Our fossil calibration, robust to varied assumptions, indicates that the cheilostome lineage and parental care therein could have Paleozoic origins, much older than the first known fossil record of cheilostomes in the Late Jurassic.
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Originally described from Greenland, Juxtacribrilina annulata (Fabricius, 1780) (previously known as Cribrilina annulata) has long been regarded as having a circumpolar, Arctic-boreal distribution. The genus Juxtacribrilina Yang, Seo, Min, Grischenko Gordon, 2018 accommodated J. annulata and three related North Pacific species formerly in Cribrilina Gray, 1848 that lack avicularia, have a reduced (hood-like, cap-like, or vestigial) ooecium closely associated with modified latero-oral spines to form an ooecial complex, and produce frontally or marginally positioned dwarf ovicellate zooids. While the recently described NW Pacific species J. mutabilis and J. flavomaris, which have a vestigial ooecium like a short, flattened spine, clearly differ from J. annulata, the differences between J. annulata and other Pacific populations remained unclear. Here we provide descriptions for five species from the North Pacific region. We identified a specimen from the Sea of Okhotsk as J. annulata. Among the other four species, J. ezoensis n. sp. has a trans-Pacific distribution (abundant at Akkeshi, Hokkaido, Japan; also detected in the Commander Islands and at Ketchikan, Southeast Alaska); J. pushkini n. sp. was found only at Ketchikan; J. dobrovolskii n. sp. was found only at Shikotan Island in the Lesser Kuril Chain; and J. tumida n. sp. was found only at Kodiak, Gulf of Alaska. These four species all differ from J. annulata in having one or two frontal pore chambers on the proximal gymnocyst of most zooids; in budding frontal dwarf ovicellate zooids from these chambers rather than from basal pore chambers; in producing dwarf zooids more abundantly; and in having ooecia that are somewhat to markedly more reduced (cap-like rather than hood-like) and more closely integrated with the modified latero-oral spines. Furthermore, in the Pacific species, the ooecium in basal zooids arises from the roof of the distal pore chamber of the maternal zooid; ovicellate zooids can thus also bud a distal autozooid and are often arranged in columnar series with other zooids. In J. annulata, the hood-like kenozooidal ooecium budded from the maternal zooid replaces the distal autozooid, and ovicellate zooids are thus usually not embedded in a columnar series.
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Briozoos , Arañas , AnimalesRESUMEN
A new abyssal cyclostome bryozoan genus and species, Vasopora ceramica n. gen., n. sp., is described from the eastern Russian exploration area of the ClarionClipperton Fracture Zone based on newly collected material from Yuzhmorgeologiya GLD419 station 421 (13.23408 N, 134.22180 W, 4809 m depth). Generic characters include an erect pedunculate colony with a distinct boundary between column and flared capitulum, short autozooidal peristomes in a single whorl, numerous alveoli, a central unidirectional sac-like gonozooid covered by a surficial network of crossed ridges continuous with adjacent rims of alveoli, a laterally opening ooeciopore, and the entire capitulum surface being minutely densely granular to subspinulate. Whereas the skeletal microstructure of the capitulum surface comprises irregular imbricated crystallites, the column has a planar-spherulitic fabric of acicular crystallites in fan-like arrays, and there are no pseudopores. The sharp boundary between capitulum and column, with their different microstructure separates Vasopora n. gen. from the two existing genera of Alyonushkidae that are found in the same environment. Vasopora n. gen. has a stalk formed of calcified exterior wall, whereas it is interior-walled in Alyonushka and Calyssopora.
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Briozoos , Lepidópteros , Thoracica , Animales , Océano Pacífico , Federación de RusiaRESUMEN
Here we describe a new hornerid, Hornera currieae n. sp. (Bryozoa: Cyclostomatida) from bathyal depths across the New Zealand region. Colonies are irregular, finely branched fans attaining ~40 mm or more in height. Key characters include: (1) thick, semi-hyaline porcellanous skeleton; (2) loss or reduction of nervi (longitudinal striae) away from growing tips; (3) sparse, threadlike cancelli; and (4) small (6187 m), widely spaced autozooidal apertures. Diagnostic hornerid traits possessed by H. currieae n. sp. include vertical ancestrular tube, periancestrular budding of daughter zooids, and skeletal ultrastructure dominated by hexagonal semi-nacre grading to pseudofoliated fabric. The abfrontal incubation chamber develops from a cryptic tube arising from the frontally positioned aperture of the fertile zooid. We used SEM, micro-CT and electron backscatter diffractometry (EBSD) to investigate the ultrastructure and internal architecture of H. currieae n. sp. EBSD reveals that crystalline c-axes of laminated crystallites are perpendicular to skeletal walls. Threadlike cancelli, which traverse secondary calcification, connect autozooidal chambers to the colony-wide hypostegal cavity. Micro-CT reveals that abfrontal cancelli usually bend proximally towards the base, but turn distally towards reproductively active regions of the colony in synchrony with gonozooid development. The zone of affected cancelli extends for 47 branch internodes below the gonozooid. We assessed whether skeletal ultrastructure was similarly affected, but neither cancellus direction, nor gonozooid proximity, were predictive of the crystallite imbrication direction. We hypothesise that (1) hornerid cancelli are active conduits for colonial metabolite transport and (2) that changes in gradients of metabolites and/or reproductive morphogens within the hypostegal cavity affect cancellus morphogenesis. Potentially, H. currieae n. sp. skeletons may preserve a record of intra-colony metabolite translocation dynamics over time.
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Anomuros , Briozoos , AnimalesRESUMEN
This short account is an invited contribution to the Zootaxa special volume 'Twenty years of Zootaxa.' Zootaxa was first published on 28 May 2001. Between this date and December 2020, 116 papers were published in Zootaxa that mention Bryozoa, comprising mostly descriptions of new species and higher taxa, but also including molecular sequencing (e.g. Fehlauer-Ale et al. 2011; Taylor et al. 2011; Franjevic et al. 2015), invasive-species research (e.g. Ryland et al. 2014; Vieira et al. 2014), checklists (e.g. Vieira et al. 2008), classification (e.g. Bock Gordon 2013), bryozoans as associates of other organisms (e.g. Rudman 2007; Chatterjee Dovgal 2020; Chatterjee et al. 2020), metazoan phylogeny (e.g. Giribet et al. 2013), biographies of historical figures who worked on bryozoans (e.g. Calder Brinkmann-Voss 2011; Calder 2015) and a catalogue of the fossil invertebrate taxa described by William Gabb (including 67 bryozoan species) (Groves Squires 2018). Of the 116 papers, 15 (13%) were open-access.
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Briozoos/clasificación , Animales , Fósiles , Publicaciones Periódicas como Asunto , FilogeniaRESUMEN
Resolution of relationships at lower taxonomic levels is crucial for answering many evolutionary questions, and as such, sufficiently varied species representation is vital. This latter goal is not always achievable with relatively fresh samples. To alleviate the difficulties in procuring rarer taxa, we have seen increasing utilization of historical specimens in building molecular phylogenies using high throughput sequencing. This effort, however, has mainly focused on large-bodied or well-studied groups, with small-bodied and under-studied taxa under-prioritized. Here, we utilize both historical and contemporary specimens, to increase the resolution of phylogenetic relationships among a group of under-studied and small-bodied metazoans, namely, cheilostome bryozoans. In this study, we pioneer the sequencing of air-dried cheilostomes, utilizing a recently developed library preparation method for low DNA input. We evaluate a de novo mitogenome assembly and two iterative methods, using the sequenced target specimen as a reference for mapping, for our sequences. In doing so, we present mitochondrial and ribosomal RNA sequences of 43 cheilostomes representing 37 species, including 14 from historical samples ranging from 50 to 149 years old. The inferred phylogenetic relationships of these samples, analyzed together with publicly available sequence data, are shown in a statistically well-supported 65 taxa and 17 genes cheilostome tree, which is also the most broadly sampled and largest to date. The robust phylogenetic placement of historical samples whose contemporary conspecifics and/or congenerics have been sequenced verifies the appropriateness of our workflow and gives confidence in the phylogenetic placement of those historical samples for which there are no close relatives sequenced. The success of our workflow is highlighted by the circularization of a total of 27 mitogenomes, seven from historical cheilostome samples. Our study highlights the potential of utilizing DNA from micro-invertebrate specimens stored in natural history collections for resolving phylogenetic relationships among species.
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Collections from relatively deep waters around the New Zealand Exclusive Economic Zone have revealed new species in the cheilostome bryozoan genus Cellaria sensu lato. We describe here seven new species: C. calculosa n. sp., C. curiosa n. sp., C. gracillima n. sp., C. major n. sp., C. spatulifera n. sp., C. stenorhyncha n. sp. and C. macricula n. sp. previously misidentified as C. humilis Moyano, 1983. Four additional species (here called spp. 1, 2, 3, 4) are left in open nomenclature since not enough key taxonomic characteristics were observed to define them as new. Furthermore, some of the newly described species have combinations of taxonomic characters that overlap with those said to characterise Paracellaria and Euginoma. The New Zealand region holds the highest species diversity of Cellaria sensu lato in the world.
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Briozoos , AnimalesRESUMEN
Understanding community assembly is a key goal in community ecology. Environmental filtering influences community assembly by excluding ill-adapted species, resulting in communities with similar functional traits. An RLQ (a four-way ordination) analysis incorporating spatial data was run on a data set of 642 species of cheilostomes (Bryozoa) from 779 New Zealand sites, and results were compared to trends in other sessile, epibenthic taxa. This revealed environmental filtering of colony form: encrusting-cemented taxa were predominant in shallow environments with hard substrata (<200 m), while erect-rooted taxa characterized deeper environments with soft substrata (>200 m). Furthermore, erect taxa found in shallow environments with high current speeds were typically jointed. Polymorphism also followed environmental gradients. External ovicells (brood chambers) were more common in deeper, low-oxygen water than immersed and internal ovicells. This may reflect the oxygen needs of the embryo or increased predation intensity in shallow environments. Bryozoans with costae tended to be found in deeper water as well, while bryozoans with calcified frontal shields were found in shallow environments with a higher concentration of CaCO3 . Avicularia did not appear to be related to environmental conditions, and changes in pivot bar structure with depth likely represent a phylogenetic signal. The importance of substratum type as a strict environmental filter suggests that anchoring structures, like rootlets, may be "key innovations" for other sessile, epibenthic taxa like sponges and ascidians.
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Briozoos , Animales , Briozoos/genética , Ecología , Nueva Zelanda , Filogenia , Polimorfismo GenéticoRESUMEN
Skeletal resorption - the physiological removal of mineralised parts by an organism - is an important morphogenetic process in bryozoans. Reports of its occurrence and function across the phylum are patchy, however, and have not previously been synthesised. Here we show that resorption occurs routinely across a wide range of bryozoan clades, colony sizes, growth forms, ontogenetic stages, body wall types, skeletal ultrastructures and mineralogies. Beginning in the early Paleozoic, different modes and functions of resorption have evolved convergently among disparate groups, highlighting its utility as a morphogenetic mode in this phylum. Its functions include branch renovation, formation of branch articulations, excavation of reproductive chambers, part-shedding, and creation of access portals for budding beyond previously formed skeletal walls. Bryozoan skeletons can be altered by resorption at microscopic, zooidal and colony-wide scales, typically with a fine degree of control and coordination. We classified resorption patterns in bryozoans according to the morphology and function of the resorption zone (window formation, abscission or excavation), timing within the life of the skeletal element resorbed (primary or secondary), and scale of operation (zooidal or multizooidal). Skeletal resorption is probably greatly underestimated in terms of its utility and role in bryozoan life history, and its prevalence across taxa, especially in fossil forms. It is reported proportionally more frequently in stenolaemates than in gymnolaemates. Some modes of resorption potentially alter or remove the spatial-temporal record of calcification preserved within a skeleton. Consequently, knowledge that resorption has occurred can be relevant for some common applications of skeletal analysis, such as palaeoenvironmental interpretation, or growth and ageing studies. To aid recognition we provide scanning electron microscopy, backscattered electron scanning electron microscopy and transmission electron microscopy examples of skeletal ultrastuctures modified by resorption.
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Briozoos , Animales , FósilesRESUMEN
The diversity of Hippothoidae (Bryozoa, Cheilostomata) in New Zealand is increased from 12 named species to 17 and the number of genera from three to five. New species are recognised in the genera Antarctothoa, Hippothoa, Jessethoa n. gen. and Neothoa (newly discovered in New Zealand waters). A new species of Plesiothoa from New South Wales is also described. Collectively, the new taxa encrust a range of substrata (a catenicellid bryozoan, brown and red macroalgae, rock and mollusc shell). The status of two existing species is changed-Hippothoa divaricata pacifica Gordon, 1984 is raised to full species, and Hippothoa watersi Morris, 1980 is used for putative Hippothoa flagellum in New Zealand. New data are given for these species and Hippothoa peristomata Gordon, 1984, and little-known Antarctothoa buskiana (Hutton, 1873) and Antarctothoa cancer (Hutton, 1873) are illustrated by scanning electron microscopy for the first time.
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Briozoos , Animales , Australasia , Microscopía Electrónica de RastreoRESUMEN
Marine organisms are a valuable source of bioactive natural products, yet bryozoan invertebrates have been relatively understudied. Herein, we report nelliellosides A and B, new secondary metabolites of the Pacific bryozoan Nelliella nelliiformis, found using NMR-guided isolation. Their structures, including absolute configurations, were elucidated using spectroscopic and chromatographic techniques. Total synthesis of the natural products and four analogues was also achieved, in addition to an assessment of their biological activity, especially kinase inhibition.
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Organismos Acuáticos/química , Briozoos/química , Inhibidores Enzimáticos/química , Nucleósidos/metabolismo , Animales , Productos Biológicos/química , Cromatografía/métodos , Inhibidores Enzimáticos/farmacología , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular/métodos , Nucleósidos/químicaRESUMEN
A new cyclostome bryozoan, Pandanipora fragilis n. sp., is described from 3453 m depth on the subequatorial Mid-Atlantic Ridge. It differs from the type species, P. helix Grischenko, Gordon Melnik, 2018, by a combination of colonial and zooidal characters. These include regular branching of a uniserial stem along the entire colony length; a straight or just slightly elevated and gently curved distal autozooidal peristomial component, forming a sharp angle with the frontal wall of the next zooid; the pattern of zooidal budding, achieved via development of a partition from the floor of the parent zooid in its distal quarter to third, leaving the proximal portion of daughter zooids not overlapping, so that preceding and subsequent zooids are not appressed along their proximal segments; props are uniformly straight and filiform, with their diameter much smaller than in P. helix; the exceptionally rare presence of slit-like pseudopores, restricted to props; and wedge-shaped crystallites on the internal surface of developing zooids, with irregular, ragged edges. The discovery of P. fragilis suggests that Pandanipora is most likely a relict element of a more-widespread ancient distribution that existed in tropical and boreal zones of both the Atlantic and Pacific Oceans prior to formation of the Isthmus of Panama in the Pliocene.
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Briozoos , Agua , Animales , Océano AtlánticoRESUMEN
Seven new species of Adeonellopsis MacGillivray, 1886 are described: Adeonellopsis macewindui, A. gracilis (endemic to New Zealand), A. gemina (New Zealand and Norfolk Island shelf), A. tasmanensis (Norfolk Island shelf and Gascoyne Seamount), A. periculosa Norfolk Island shelf) and A. wassi and A. minor (New South Wales shelf). All have flattened staghorn branches, which range in width from 0.8 to 5 mm, depending on species. Based on underwater photos, the largest species, A. macewindui n. sp. forms locally significant habitat on fiord walls and parts of the continental shelf in New Zealand, sometimes in association with A. gemina n. sp.. The latter can survive as isolated fragments that can regenerate from broken ends. Three species have a number of large gonozooids at selected locations on their branches and two of these species have vestigial ooecia in their gonozooids, recorded for the first time in Adeonidae. The remaining four species have among their autozooids only a few zooids that are a little larger, with larger compound spiramina. These are suggested to function as gonozooids, representing the larger end of a size spectrum for reproductive zooids, of which those at the lower end are the same size as autozooids. The encrusting Australian species known as Adeonellopsis baccata (Hutton, 1878) is transferred to Reptadeonella as Reptadeonella baccata n. comb..