Systematics and character evolution of capitate hydrozoans.

Capitate hydrozoans are a morphologically and ecologically diverse hydrozoan suborder, currently including about 200 species. Being grouped in two clades, Corynida and Zancleida, these hydrozoans still show a number of taxonomic uncertainties at the species, genus and family levels. Many Capitata species established symbiotic relationships with other benthic organisms, including bryozoans, other cnidarians, molluscs and poriferans, as well as with planktonic dinoflagellates for mixotrophic relationships and with bacteria for thiotrophic ectosymbioses.

Multiple evolutionary transitions of reproductive strategies in a phylum of aquatic colonial invertebrates.

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.

Taxonomy, ecology and zoogeography of the Recent species of Rhamphostomella Lorenz, 1886 and Mixtoscutella n. gen. (Bryozoa, Cheilostomata).

Twenty-four Recent species of the boreal-Arctic and Pacific cheilostome bryozoan genus Rhamphostomella are described. The species R. tatarica and R.

Paleozoic origins of cheilostome bryozoans and their parental care inferred by a new genome-skimmed phylogeny.

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.

The Cribrilina annulata" problem and new species of Juxtacribrilina (Bryozoa: Cheilostomata: Cribrilinidae) from the North Pacific.

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.

Mitochondrial gene order of the freshwater bryozoan Cristatella mucedo retains ancestral lophotrochozoan features.

Bryozoans are aquatic colonial suspension-feeders abundant in many marine and freshwater benthic communities. At the same time, the phylum is under studied on both morphological and molecular levels, and its position on the metazoan tree of life is still disputed. Bryozoa include the exclusively marine Stenolaemata, predominantly marine Gymnolaemata and exclusively freshwater Phylactolaemata.

Cryptic species and host specificity in the bryozoan-associated hydrozoan Zanclea divergens (Hydrozoa, Zancleidae).

Zanclea divergens is a tropical hydrozoan living in symbiotic association with bryozoans and currently reported from Papua New Guinea, Indonesia, and Maldives. Here, we used an integrative approach to assess the morpho-molecular diversity of the species across the Indo-Pacific. Phylogenetic and species delimitation analyses based on seven mitochondrial and nuclear loci revealed four well-supported molecular lineages corresponding to cryptic species, and representing a Pacific clade, an Indian clade, and two Red Sea clades.

Global Distribution and Variation of the Invasive Cheilostome Bryozoan .

Viable populations of the cheilostome bryozoan Ito, Onishi & Dick exist in the NW Pacific (Russian Far East and northern Japan), NE Atlantic (Scandinavia and Scotland), and NW Atlantic (Maine, USA). The first NE and NW Atlantic records are from Norway (2008) and Casco Bay, Maine, USA (2018), respectively, indicating a relatively recent introduction to the region. Mitochondrial COI gene sequences from North Atlantic populations (Sweden, Norway, and Maine) showed two haplotypes differing by one substitution, but differed from two haplotypes from Akkeshi, northern Japan, by 6-8 substitutions.

Key novelties in the evolution of the aquatic colonial phylum Bryozoa: evidence from soft body morphology.

Molecular techniques are currently the leading tools for reconstructing phylogenetic relationships, but our understanding of ancestral, plesiomorphic and apomorphic characters requires the study of the morphology of extant forms for testing these phylogenies and for reconstructing character evolution. This review highlights the potential of soft body morphology for inferring the evolution and phylogeny of the lophotrochozoan phylum Bryozoa. This colonial taxon comprises aquatic coelomate filter-feeders that dominate many benthic communities, both marine and freshwater.

Sexual reproduction of the placental brooder Celleporella hyalina (Bryozoa, Cheilostomata) in the White Sea.

The evolution of parental care is a central field in many ecological and evolutionary studies, but integral approaches encompassing various life-history traits are not common. Else, the structure, development and functioning of the placental analogues in invertebrates are poorly understood. Here, we describe the life-history, sexual colony dynamics, oogenesis, fertilization and brooding in the boreal-Arctic cheilostome bryozoan Celleporella hyalina.

Morphology of the bryozoan Cinctipora elegans (Cyclostomata, Cinctiporidae) with first data on its sexual reproduction and the cyclostome neuro-muscular system.

Background: Cyclostome bryozoans are an ancient group of marine colonial suspension-feeders comprising approximately 700 extant species. Previous morphological studies are mainly restricted to skeletal characters whereas data on soft tissues obtained by state-of-the-art methods are still lacking. In order to contribute to issues related to cyclostome ground pattern reconstruction, we analyzed the morphology of the neuromuscular system Cinctipora elegans by means of immunocytochemical staining, confocal laser scanning microscopy, histological sections and microCT imaging.

Climate Warming as a Possible Trigger of Keystone Mussel Population Decline in Oligotrophic Rivers at the Continental Scale.

The effects of climate change on oligotrophic rivers and their communities are almost unknown, albeit these ecosystems are the primary habitat of the critically endangered freshwater pearl mussel and its host fishes, salmonids. The distribution and abundance of pearl mussels have drastically decreased throughout Europe over the last century, particularly within the southern part of the range, but causes of this wide-scale extinction process are unclear. Here we estimate the effects of climate change on pearl mussels based on historical and recent samples from 50 rivers and 6 countries across Europe.

Novel brominated metabolites from Bryozoa: a functional analysis.

Marine invertebrates are a promising source of novel natural products with biological activities. The phylum Bryozoa is relatively under-investigated in this context, although a number of compounds with medical potential has been discovered in recent years. Here, we report on the novel group of brominated metabolites from the bryozoan Terminoflustra membranaceatruncata, including analysis of biological activities of the tribrominated terminoflustrindole A (Cm-1) and the structures of the related dibrominated variants terminoflustrindoles B and C.

Systematics and diversity of deep-water Cheilostomata (Bryozoa) from Galicia Bank (NE Atlantic).

Galicia Bank is a large seamount situated c. 200 km off NW Iberia with a minimum depth of 600 m. It was recently included in Natura 2000, an EU-wide network of nature protection areas.

Comparative morphology of the nervous system in three phylactolaemate bryozoans.

Background: Though some elements of the bryozoan nervous system were discovered 180 years ago, few studies of their neuromorphology have been undertaken since that time. As a result the general picture of the bryozoan nervous system structure is incomplete in respect of details and fragmentary in respect of taxonomic coverage.

Results: The nervous system of three common European freshwater bryozoans - Cristatella mucedo, Plumatella repens (both with a horseshoe-shaped lophophore) and Fredericella sultana (with a circular lophophore) had numerous differences in the details of the structure but the general neuroarchitecture is similar.

Matrotrophy and placentation in invertebrates: a new paradigm.

Matrotrophy, the continuous extra-vitelline supply of nutrients from the parent to the progeny during gestation, is one of the masterpieces of nature, contributing to offspring fitness and often correlated with evolutionary diversification. The most elaborate form of matrotrophy-placentotrophy-is well known for its broad occurrence among vertebrates, but the comparative distribution and structural diversity of matrotrophic expression among invertebrates is wanting. In the first comprehensive analysis of matrotrophy across the animal kingdom, we report that regardless of the degree of expression, it is established or inferred in at least 21 of 34 animal phyla, significantly exceeding previous accounts and changing the old paradigm that these phenomena are infrequent among invertebrates.

New species of Bryozoa from Madeira associated with rhodoliths.

Four new species of cheilostomate Bryozoa encrusting rhodoliths on Maërl beds are described from material collected at a single locality at Madeira Island. These are Coronellina atlantica n. sp.

From incipient to substantial: evolution of placentotrophy in a phylum of aquatic colonial invertebrates.

Matrotrophy has long been known in invertebrates, but it is still poorly understood and has never been reviewed. A striking example of matrotrophy (namely, placentotrophy) is provided by the Bryozoa, a medium-sized phylum of the aquatic colonial filter feeders. Here I report on an extensive anatomical study of placental analogues in 21 species of the bryozoan order Cheilostomata, offering the first review on matrotrophy among aquatic invertebrates.

The placental analogue and the pattern of sexual reproduction in the cheilostome bryozoan Bicellariella ciliata (Gymnolaemata).

Background: Matrotrophy or extraembryonic nutrition - transfer of nutrients from mother to embryo during gestation - is well known and thoroughly studied among vertebrates, but still poorly understood in invertebrates. The current paper focuses on the anatomy and ultrastructure of the oogenesis and placentotrophy as well as formation of the brood chamber (ovicell) in the cheilostome bryozoan Bicellariella ciliata (Linnaeus, 1758). Our research aimed to combine these aspects of the sexual reproduction into an integral picture, highlighting the role of the primitive placenta-like system in the evolution of bryozoan reproductive patterns.

Comparative anatomy of internal incubational sacs in cupuladriid bryozoans and the evolution of brooding in free-living cheilostomes.

Numerous gross morphological attributes are shared among unrelated free-living bryozoans revealing convergent evolution associated with functional demands of living on soft sediments. Here, we show that the reproductive structures across free-living groups evolved convergently. The most prominent convergent traits are the collective reduction of external brood chambers (ovicells) and the acquisition of internal brooding.

The internal-brooding apparatus in the bryozoan genus Cauloramphus (Cheilostomata: Calloporidae) and its inferred homology to ovicells.

We studied by SEM the external morphology of the ooecium in eight bryozoans of the genus Cauloramphus (Cheilostomata, Calloporidae): C. spinifer, C. variegatus, C.

Comparative anatomical study of internal brooding in three anascan bryozoans (Cheilostomata) and its taxonomic and evolutionary implications.

The anatomical structure of internal sacs for embryonic incubation was studied using SEM and light microscopy in three cheilostome bryozoans-Nematoflustra flagellata (Waters,1904), Gontarella sp., and Biflustra perfragilis MacGillivray, 1881. In all these species the brood sac is located in the distal half of the maternal (egg-producing) autozooid, being a conspicuous invagination of the body wall.