Protomelission is an early dasyclad alga and not a Cambrian bryozoan.

The animal phyla and their associated body plans originate from a singular burst of evolution occurring during the Cambrian period, over 500 million years ago1. The phylum Bryozoa, the colonial 'moss animals', have been the exception: convincing skeletons of this biomineralizing clade have been absent from Cambrian strata, in part because potential bryozoan fossils are difficult to distinguish from the modular skeletons of other animal and algal groups2,3. At present, the strongest candidate4 is the phosphatic microfossil Protomelission5. Here we describe exceptionally preserved non-mineralized anatomy in Protomelission-like macrofossils from the Xiaoshiba Lagerstätte6. Taken alongside the detailed skeletal construction and the potential taphonomic origin of 'zooid apertures', we consider that Protomelission is better interpreted as the earliest dasycladalean green alga-emphasizing the ecological role of benthic photosynthesizers in early Cambrian communities. Under this interpretation, Protomelission cannot inform the origins of the bryozoan body plan; despite a growing number of promising candidates7-9, there remain no unequivocal bryozoans of Cambrian age.

Fossil evidence unveils an early Cambrian origin for Bryozoa.

Bryozoans (also known as ectoprocts or moss animals) are aquatic, dominantly sessile, filter-feeding lophophorates that construct an organic or calcareous modular colonial (clonal) exoskeleton1-3. The presence of six major orders of bryozoans with advanced polymorphisms in lower Ordovician rocks strongly suggests a Cambrian origin for the largest and most diverse lophophorate phylum2,4-8. However, a lack of convincing bryozoan fossils from the Cambrian period has hampered resolution of the true origins and character assembly of the earliest members of the group. Here we interpret the millimetric, erect, bilaminate, secondarily phosphatized fossil Protomelission gatehousei9 from the early Cambrian of Australia and South China as a potential stem-group bryozoan. The monomorphic zooid capsules, modular construction, organic composition and simple linear budding growth geometry represent a mixture of organic Gymnolaemata and biomineralized Stenolaemata character traits, with phylogenetic analyses identifying P. gatehousei as a stem-group bryozoan. This aligns the origin of phylum Bryozoa with all other skeletonized phyla in Cambrian Age 3, pushing back its first occurrence by approximately 35 million years. It also reconciles the fossil record with molecular clock estimations of an early Cambrian origination and subsequent Ordovician radiation of Bryozoa following the acquisition of a carbonate skeleton10-13.

A broadly resolved molecular phylogeny of New Zealand cheilostome bryozoans as a framework for hypotheses of morphological evolution.

Larger molecular phylogenies based on ever more genes are becoming commonplace with the advent of cheaper and more streamlined sequencing and bioinformatics pipelines. However, many groups of inconspicuous but no less evolutionarily or ecologically important marine invertebrates are still neglected in the quest for understanding species- and higher-level phylogenetic relationships. Here, we alleviate this issue by presenting the molecular sequences of 165 cheilostome bryozoan species from New Zealand waters. New Zealand is our geographic region of choice as its cheilostome fauna is taxonomically, functionally and ecologically diverse, and better characterized than many other such faunas in the world. Using this most taxonomically broadly-sampled and statistically-supported cheilostome phylogeny comprising 214 species, when including previously published sequences, and 17 genes (2 nuclear and 15 mitochondrial) we tested several existing systematic hypotheses based solely on morphological observations. We find that lower taxonomic level hypotheses (species and genera) are robust while our inferred trees did not reflect current higher-level systematics (family and above), illustrating a general need for the rethinking of current hypotheses. To illustrate the utility of our new phylogeny, we reconstruct the evolutionary history of frontal shields (i.e., a calcified body-wall layer in ascus-bearing cheilostomes) and ask if its presence has any bearing on the diversification rates of cheilostomes.

The Phylum Bryozoa: From Biology to Biomedical Potential.

Less than one percent of marine natural products characterized since 1963 have been obtained from the phylum Bryozoa which, therefore, still represents a huge reservoir for the discovery of bioactive metabolites with its ~6000 described species. The current review is designed to highlight how bryozoans use sophisticated chemical defenses against their numerous predators and competitors, and which can be harbored for medicinal uses. This review collates all currently available chemoecological data about bryozoans and lists potential applications/benefits for human health. The core of the current review relates to the potential of bryozoan metabolites in human diseases with particular attention to viral, brain, and parasitic diseases. It additionally weighs the pros and cons of total syntheses of some bryozoan metabolites versus the synthesis of non-natural analogues, and explores the hopes put into the development of biotechnological approaches to provide sustainable amounts of bryozoan metabolites without harming the natural environment.

A genome-skimmed phylogeny of a widespread bryozoan family, Adeonidae.

BACKGROUND: Understanding the phylogenetic relationships among species is one of the main goals of systematic biology. Simultaneously, credible phylogenetic hypotheses are often the first requirement for unveiling the evolutionary history of traits and for modelling macroevolutionary processes. However, many non-model taxa have not yet been sequenced to an extent such that statistically well-supported molecular phylogenies can be constructed for these purposes. Here, we use a genome-skimming approach to extract sequence information for 15 mitochondrial and 2 ribosomal operon genes from the cheilostome bryozoan family, Adeonidae, Busk, 1884, whose current systematics is based purely on morphological traits. The members of the Adeonidae are, like all cheilostome bryozoans, benthic, colonial, marine organisms. Adeonids are also geographically widely-distributed, often locally common, and are sometimes important habitat-builders. RESULTS: We successfully genome-skimmed 35 adeonid colonies representing 6 genera (Adeona, Adeonellopsis, Bracebridgia, Adeonella, Laminopora and Cucullipora). We also contributed 16 new, circularised mitochondrial genomes to the eight previously published for cheilostome bryozoans. Using the aforementioned mitochondrial and ribosomal genes, we inferred the relationships among these 35 samples. Contrary to some previous suggestions, the Adeonidae is a robustly supported monophyletic clade. However, the genera Adeonella and Laminopora are in need of revision: Adeonella is polyphyletic and Laminopora paraphyletically forms a clade with some Adeonella species. Additionally, we assign a sequence clustering identity using cox1 barcoding region of 99% at the species and 83% at the genus level. CONCLUSIONS: We provide sequence data, obtained via genome-skimming, that greatly increases the resolution of the phylogenetic relationships within the adeonids. We present a highly-supported topology based on 17 genes and substantially increase availability of circularised cheilostome mitochondrial genomes, and highlight how we can extend our pipeline to other bryozoans.

Phylogenomics of Lophotrochozoa with Consideration of Systematic Error.

Phylogenomic studies have improved understanding of deep metazoan phylogeny and show promise for resolving incongruences among analyses based on limited numbers of loci. One region of the animal tree that has been especially difficult to resolve, even with phylogenomic approaches, is relationships within Lophotrochozoa (the animal clade that includes molluscs, annelids, and flatworms among others). Lack of resolution in phylogenomic analyses could be due to insufficient phylogenetic signal, limitations in taxon and/or gene sampling, or systematic error. Here, we investigated why lophotrochozoan phylogeny has been such a difficult question to answer by identifying and reducing sources of systematic error. We supplemented existing data with 32 new transcriptomes spanning the diversity of Lophotrochozoa and constructed a new set of Lophotrochozoa-specific core orthologs. Of these, 638 orthologous groups (OGs) passed strict screening for paralogy using a tree-based approach. In order to reduce possible sources of systematic error, we calculated branch-length heterogeneity, evolutionary rate, percent missing data, compositional bias, and saturation for each OG and analyzed increasingly stricter subsets of only the most stringent (best) OGs for these five variables. Principal component analysis of the values for each factor examined for each OG revealed that compositional heterogeneity and average patristic distance contributed most to the variance observed along the first principal component while branch-length heterogeneity and, to a lesser extent, saturation contributed most to the variance observed along the second. Missing data did not strongly contribute to either. Additional sensitivity analyses examined effects of removing taxa with heterogeneous branch lengths, large amounts of missing data, and compositional heterogeneity. Although our analyses do not unambiguously resolve lophotrochozoan phylogeny, we advance the field by reducing the list of viable hypotheses. Moreover, our systematic approach for dissection of phylogenomic data can be applied to explore sources of incongruence and poor support in any phylogenomic data set. [Annelida; Brachiopoda; Bryozoa; Entoprocta; Mollusca; Nemertea; Phoronida; Platyzoa; Polyzoa; Spiralia; Trochozoa.].

Reconstructing the muscular ground pattern of phylactolaemate bryozoans: first data from gelatinous representatives.

BACKGROUND: Phylactolaemata is commonly regarded the earliest branch within Bryozoa and thus the sister group to the other bryozoan taxa, Cyclostomata and Gymnolaemata. Therefore, the taxon is important for the reconstruction of the bryozoan morphological ground pattern. In this study the myoanatomy of Pectinatella magnifica, Cristatella mucedo and Hyalinella punctata was analysed by means of histology, f-actin staining and confocal laser-scanning microscopy in order to fill gaps in knowledge concerning the myoanatomy of Phylactolaemata. RESULTS: The retractor muscles and muscles of the aperture, gut, body wall, tentacle sheath, lophophore constitute the most prominent muscular subsets in these species. The lophophore shows longitudinal muscle bands in the tentacles, lophophoral arm muscles, epistome musculature and hitherto undescribed muscles of the ring canal. In general the muscular system of the three species is very similar with differences mainly in the body wall, tentacle sheath and epistome. The body wall contains an orthogonal grid of musculature. The epistome exhibits either a muscular meshwork in the epistomal wall or muscle fibers traversing the epistomal cavity. The whole tentacle sheath possesses a regular mesh of muscles in Pectinatella and Cristatella, whereas circular muscles are limited to the tentacle sheath base in Hyalinella. CONCLUSION: This study is the first to describe muscles of the ring canal and contributes to reconstructing muscular features for the last common ancestor of all bryozoans. The data available suggest that two longitudinal muscle bands in the tentacles, as well as retractor muscles and longitudinal and circular muscles in the tentacle sheath, were present in the last common bryozoan ancestor. Comparisons among bryozoans shows that several apomorphies are present in the myoanatomy of each class- level taxon such as the epistomal musculature and musculature of the lophophoral arms in phylactolaemates, annular muscles in cyclostomes and parietal muscles in gymnolaemates.

Comparative analysis of the nervous system structure of polymorphic zooids in marine bryozoans.

The nervous system structure was compared for the first time in avicularia and vibracula in seven species of the cheilostome bryozoans from six families by immunohistochemical methods and confocal scanning microscopy. Regardless of significant differences in heterozooid shape, size, and position in a colony, their muscular and nervous systems have a common structure, which suggests their parallel evolution.

The nervous system of the lophophore in the ctenostome Amathia gracilis provides insight into the morphology of ancestral ectoprocts and the monophyly of the lophophorates.

BACKGROUND: The Bryozoa (=Ectoprocta) is a large group of bilaterians that exhibit great variability in the innervation of tentacles and in the organization of the cerebral ganglion. Investigations of bryozoans from different groups may contribute to the reconstruction of the bryozoan nervous system bauplan. A detailed investigation of the polypide nervous system of the ctenostome bryozoan Amathia gracilis is reported here. RESULTS: The cerebral ganglion displays prominent zonality and has at least three zones: proximal, central, and distal. The proximal zone is the most developed and contains two large perikarya giving rise to the tentacle sheath nerves. The neuroepithelial organization of the cerebral ganglion is revealed. The tiny lumen of the cerebral ganglion is represented by narrow spaces between the apical projections of the perikarya of the central zone. The cerebral ganglion gives rise to five groups of main neurite bundles of the lophophore and the tentacle sheath: the circum-oral nerve ring, the lophophoral dorso-lateral nerves, the pharyngeal and visceral neurite bundles, the outer nerve ring, and the tentacle sheath nerves. Serotonin-like immunoreactive nerve system of polypide includes eight large perikarya located between tentacles bases. There are two analmost and six oralmost perikarya with prominent serotonergic "gap" between them. Based on the characteristics of their innervations, the tentacles can be subdivided into two groups: four that are near the anus and six that are near the mouth. Two longitudinal neurite bundles - medio-frontal and abfrontal - extend along each tentacle. CONCLUSION: The zonality of the cerebral ganglion, the presence of three commissures, and location of the main nerves emanating from each zone might have caused by directive innervation of the various parts of the body: the tentacles sheath, the lophohpore, and the digestive tract. Two alternative scenarios of bryozoan lophophore evolution are discussed. The arrangement of large serotonin-like immunoreactive perikarya differs from the pattern previously described in ctenostome bryozoans. In accordance with its position relative to the same organs (tentacles, anus, and mouth), the lophophore outer nerve ring corresponds to the brachiopod lower brachial nerve and to the phoronid tentacular nerve ring. The presence of the outer nerve ring makes the lophophore innervation within the group (clade) of lophophorates similar and provides additional morphological evidence of the lophophore homology and monophyly of the lophophorates.

Interspecific interactions through 2 million years: are competitive outcomes predictable?

Ecological interactions affect the survival and reproduction of individuals. However, ecological interactions are notoriously difficult to measure in extinct populations, hindering our understanding of how the outcomes of interactions such as competition vary in time and influence long-term evolutionary changes. Here, the outcomes of spatial competition in a temporally continuous community over evolutionary timescales are presented for the first time. Our research domain is encrusting cheilostome bryozoans from the Wanganui Basin of New Zealand over a ca 2 Myr time period (Pleistocene to Recent). We find that a subset of species can be identified as consistent winners, and others as consistent losers, in the sense that they win or lose interspecific competitive encounters statistically more often than the null hypothesis of 50%. Most species do not improve or worsen in their competitive abilities through the 2 Myr period, but a minority of species are winners in some intervals and losers in others. We found that conspecifics tend to cluster spatially and interact more often than expected under a null hypothesis: most of these are stand-off interactions where the two colonies involved stopped growing at edges of encounter. Counterintuitively, competitive ability has no bearing on ecological dominance.

Distribution of serotonin and FMRF-amide in the nervous system of different zooidal types of cheilostome bryozoa: A case study of Arctonula arctica.

In the White Sea bryozoans Arctonula arctica, the structure of the nervous system and distribution of 5-hydroxytryptamine (5-HT) and FMRF-amide were studied for the first time using immunohistochemical methods and confocal scanning microscopy. The neurotransmitters studied have been actively involved into the integrative processes, gut functioning, and regulation of motion activity. In avicularia, 5-HT and FMRF-amide receptors are capable of performing the same functions, except for participation in the gut functioning, because they have no digestive system.

The serotonin-lir nervous system of the Bryozoa (Lophotrochozoa): a general pattern in the Gymnolaemata and implications for lophophore evolution of the phylum.

BACKGROUND: Serotonin represents an evolutionary ancient neurotransmitter that is ubiquitously found among animals including the lophotrochozoan phylum Bryozoa, a group of colonial filter-feeders. Comparatively little is known on their nervous system, and data on their serotonin-lir nervous system currently are mostly limited to the basal phylactolaemates. Previous investigations indicated a common ground-pattern of the serotonin-lir nervous system in these animals, but in order to assess this on a larger scale, 21 gymnolaemate species from 21 genera were comparatively analysed herein. METHODS: Twenty-one species from 21 gymnolaemate genera were analysed by immunocytochemical stainings and confocal laser scanning microscopy. RESULTS: In all species the serotonin-lir signal is concentrated in the cerebral ganglion from where a nerve tract emanates laterally and traverses orally to engulf the foregut. Serotonin-lir perikarya are situated at the base of the tentacles that almost always correspond to the number of tentacles minus two. The oral side in almost all species shows three serotonin-lir perikarya followed by a 'serotonergic gap' that to our knowledge is not reflected in the morphology of the nervous system. Some species show additional serotonin-lir signal in tentacle nerves, visceral innervation and pore complexes. Paludicella articulata is exceptional as it shows signal in the latero-visceral nerves with serotonin-lir perikarya in the esophagus, parts of the tentacle sheath nerves as well as the frontal body wall around the parietal muscle bundles. CONCLUSIONS: In general, the serotonin-lir nervous system in the Bryozoa shows a consistent pattern among its different clades with few deviations. Preliminary data on phylactolaemates suggest the presence of a 'serotonergic gap' similar to gymnolaemates. Both show a subset of oral tentacles and the remaining tentacles in gymnolaemates which correspond to the lateral tentacles of phylactolaemates. The lophophoral concavity lacks serotonin-lir perikarya indicating that due to their larger sizes and increased tentacle number, the horse-shoe shaped arrangement could represent an apomorphy of phylactolaemates.

A new Fenestrulina (Bryozoa, Cheilostomata) commensal with tube-dwelling anemones (Cnidaria, Ceriantharia) in the tropical southwestern Atlantic.

A new species of cheilostome bryozoan, Fenestrulina commensalis n. sp., was collected in December 2008 by scuba at 5-10 meters depth at Guaibura Beach, Guarapari, Espírito Santo state, southeastern Brazil. The specimen was found associated with tubes of the cerianthid Pachycerianthus sp., representing the first commensal association between a bryozoan and a tube-dwelling anemone. Fenestrulina commensalis n. sp. is the third species of the genus found in Brazilian waters; it is distinguished from other Atlantic species of Fenestrulina by its small angular orificial condyles, a single oral spine and basal anchoring rhizoids arising from abfrontal pore chambers. Morphological adaptations to encrust the tubes of cerianthids include anchoring rootlets and weakly contiguous zooids. These morphological features allow the colony the flexibility to grow around the tube and feed relatively undisturbed by silt and detritus, being raised well above the soft-sediment substratum in which the tube-anemone grows.

Two new species of cheilostome bryozoans from the South Atlantic Ocean .

Two new species of cheilostome bryozoans are described from Bahia and Espírito Santo States, Brazil-Calyptooecia conuma n. sp. and Hippotrema fissurata n. sp. Both genera are registered for the first time in the South Atlantic Ocean. Inter alia, Calyptooecia conuma n. sp. is characterized by the presence of dimorphic brooding zooids with relatively small orifices and no perioral tubercles, contrasting with bigger non-brooding zooids having larger orifices surrounded by perioral tubercles. Hippotrema fissurata n. sp. differs from congeners in colony morphology and colour, in details of the ooecium and in zooidal metrics. Specimens were collected on varied substrata, commonly calcareous nodules and shells as well as other bryozoans and sponges. 

First occurrence of the non-native bryozoan Schizoporella japonica Ortmann (1890) in Western Europe.

Schizoporella japonica Ortmann was described from Japan but was subsequently introduced on Pacific oysters to the Pacific coast of North America, where it is now well established. In this paper we record it for the first time in European waters. The initial discovery was in a marina at Holyhead, North Wales, in July 2010 but S. japonica has since been observed abundantly in the Orkney Islands (from May 2011) and, subsequently, at other localities in northern Scotland. Introduction seems most likely to have been on an ocean-going vessel. The British material is here fully described and illustrated with SEMs and colour photographs; some unusual characters are discussed. Unlike other recently introduced bryozoans, S. japonica is a cold-water species and its breeding season in Britain extends through the winter. Extensive confusion between this and other species of Schizoporella on the west coast of Canada and the USA led us to make thorough morphometric comparisons between the species concerned (Schizoporella unicornis (Johnston in Wood), Schizoporella errata (Waters) and Schizoporella pseudoerrata Soule, Soule and Chaney). Zooid size in cheilostomate bryozoans is variable and often an unreliable character for species separation but shape (and therefore ratios between variables, which are independent of size) are often valuable: S. japonica zooids have a much greater length:width ratio than the other species. Density of frontal pseudopores provides a useful discriminatory character. Schizoporella unicornis, repeatedly reported in error from the Pacific coast of North America, does not occur there; it is a European species. Full comparisons are made between S. japonica and S. unicornis for European identification and between S. japonica, S. errata and S. pseudoerrata (which are also illustrated) for North American localities.

New phylogenomic data support the monophyly of Lophophorata and an Ectoproct-Phoronid clade and indicate that Polyzoa and Kryptrochozoa are caused by systematic bias.

BACKGROUND: Within the complex metazoan phylogeny, the relationships of the three lophophorate lineages, ectoprocts, brachiopods and phoronids, are particularly elusive. To shed further light on this issue, we present phylogenomic analyses of 196 genes from 58 bilaterian taxa, paying particular attention to the influence of compositional heterogeneity. RESULTS: The phylogenetic analyses strongly support the monophyly of Lophophorata and a sister-group relationship between Ectoprocta and Phoronida. Our results contrast previous findings based on rDNA sequences and phylogenomic datasets which supported monophyletic Polyzoa (= Bryozoa sensu lato) including Ectoprocta, Entoprocta and Cycliophora, Brachiozoa including Brachiopoda and Phoronida as well as Kryptrochozoa including Brachiopoda, Phoronida and Nemertea, thus rendering Lophophorata polyphyletic. Our attempts to identify the causes for the conflicting results revealed that Polyzoa, Brachiozoa and Kryptrochozoa are supported by character subsets with deviating amino acid compositions, whereas there is no indication for compositional heterogeneity in the character subsets supporting the monophyly of Lophophorata. CONCLUSION: Our results indicate that the support for Polyzoa, Brachiozoa and Kryptrochozoa gathered so far is likely an artifact caused by compositional bias. The monophyly of Lophophorata implies that the horseshoe-shaped mesosomal lophophore, the tentacular feeding apparatus of ectoprocts, phoronids and brachiopods is, indeed, a synapomorphy of the lophophorate lineages. The same may apply to radial cleavage. However, among phoronids also spiral cleavage is known. This suggests that the cleavage pattern is highly plastic and has changed several times within lophophorates. The sister group relationship of ectoprocts and phoronids is in accordance with the interpretation of the eversion of a ventral invagination at the beginning of metamorphosis as a common derived feature of these taxa.

Brachyuran and anomuran crabs associated with Schizoporella unicornis (Ectoprocta, Cheilostomata) from southeastern Brazil.

The main goals of this investigation were to describe the community structure of anomuran and brachyuran crabs inhabiting reefs constituted by colonies of Schizoporella unicornis, and to provide a species importance ranking for this community. Collections were carried out on S. unicornis reefs at two-month intervals from May 2003 to May 2004, in the rocky sublittoral of the southeastern Brazilian coast. Relative abundance and occurrence were used to rank these species in the hierarchy importance. A total of 2,018 individuals were obtained, in 11 families, 22 genera and 31 species. Porcellanidae and Pilumnidae were the most abundant families, comprising respectively almost 60% and 15% of individuals sampled. The species ranking indicated four main groups A, B, C and D, with group A subdivided. Subgroup A1 contained 9 species, including the species of greatest ecological importance for community regarding abundance and occurrence. The great abundance of crabs associated with S. unicornis seems to be the result of its recognized importance during the crab developmental cycle, and as shelter and food for some Decapod species. These observations reveal the importance of conserving the areas occupied by these reef colonies, which appear to be an important environment for maintaining local biodiversity.

Systematics of interstitial encrusting bryozoans from southeastern Brazil.

This paper describes 22 species of marine bryozoans found in the sand-grain-encrusting interstitial epifauna of the northeast coast of Sao Paulo state, Brazil: one new cyclostome, Disporella calcitrapa sp. nov., and 21 cheilostomes. Sixteen of the cheilostomes are new species, and three represent new genera. They are Ammatophora arenacea sp. nov., Discoporella gemmulifera sp. nov., Puellina caraguata sp. nov., Puellina tuba sp. nov., Rosulapelta rosetta gen. et sp. nov., Collarina spicata sp. nov., Hippothoa calcicola sp. nov., Trypostega ilhabelae sp. nov., Reptadeonella granulosa sp. nov., Drepanophora irregularis sp. nov., Allotherenia sabulosa gen. et sp. nov., Bryopesanser tilbrooki sp. nov., Psammocleidochasma tridentatum gen. et sp. nov., Celleporina abstrusa sp. nov., Hippoporella castellana sp. nov., and Hippoporella sabulonis sp. nov. Other species found in this habitat, Alderina smitti, Cymulopora uniserialis, Vibracellina laxibasis, Akatopora leucocypha, and Smittipora sawayai, have previously been described. The family Cymuloporidae fam. nov. is erected for Cymulopora and Crepis. The occurrence in this habitat of living colonies of bryozoans more characteristic of larger subtidal shell substrata indicates the potential importance of an interstitial refuge in maintaining and dispersing encrusting bryozoan populations along continental shelves where larger substrata are absent or rare.

Cradoscrupocellaria, a new bryozoan genus for Scrupocellaria bertholletii (Audouin) and related species (Cheilostomata, Candidae): taxonomy, biodiversity and distribution.

A new genus, Cradoscrupocellaria n. gen., is erected for Scrupocellaria bertholletii (Audouin, 1826), reported as widespread in tropical and subtropical waters. Here we select a neotype of this species in order to establish its identity and distinguish it from morphologically similar species. We include redescriptions and figures of additional species now assigned to this new genus: Cradoscrupocellaria curacaoensis (Fransen, 1986) n. comb., Cradoscrupocellaria hirsuta (Jullien & Calvet, 1903) n. comb., and Cradoscrupocellaria macrorhyncha (Gautier, 1962) n. comb. Five additional species are as-signed to the genus: Cradoscrupocellaria ellisi (Vieira & Spencer Jones, 2012) n. comb., Cradoscrupocellaria nanshaensis (Liu, 1991) n. comb., Cradoscrupocellaria reptans (Linnaeus, 1758) n. comb., Cradoscrupocellaria serrata (Waters, 1909) n. comb., and Cradoscrupocellaria tenuirostris (Osburn, 1950) n. comb. Eighteen new species are described: Cra-doscrupocellaria aegyptiana n. sp., Cradoscrupocellaria arisaigensis n. sp., Cradoscrupocellaria atlantica n. sp., Cradoscrupocellaria calypso n. sp., Cradoscrupocellaria floridana n. sp., Cradoscrupocellaria galapagensis n. sp., Cradoscrupocellaria gautieri n. sp., Cradoscrupocellaria gorgonensis n. sp., Cradoscrupocellaria hastingsae n. sp., Cradoscrupocellaria insularis n. sp., Cradoscrupocellaria jamaicensis n. sp., Cradoscrupocellaria lagaaiji n. sp., Cradoscrupocellaria macrorhynchoides n. sp., Cradoscrupocellaria makua n. sp., Cradoscrupocellaria marcusorum n. sp., Cradoscrupocellaria normani n. sp., Cradoscrupocellaria odonoghuei n. sp., and Cradoscrupocellaria osburni n. sp.

The amathiiform Ctenostomata (phylum Bryozoa) of New Zealand--including four new species, two of them of probable alien origin.

The status of the vesiculariid ctenostome genus Amathia in New Zealand has been evaluated on the basis of all known material, including historic specimens in museums and those newly collected during formal surveillance of ports, harbours and vessels for possible alien species. Eight species are recognised, four of them new to science. Amathia gracei n. sp. and Amathia zealandica n. sp. are the only apparently endemic species. Amathia chimonidesi n. sp. appears to be a previously unrecognised alien species and is known only from shipping harbours and/or yacht marinas and some nearby beaches. Amathia similis n. sp. has been known in the Auckland area since the 1960s but was confused with A. distans Busk. Amathia bicornis (Tenison-Woods), A. biseriata Krauss, A. lamourouxi Chimonides and A. wilsoni Kirkpatrick are Australasian species that occur naturally on both sides of the Tasman Sea. Of this latter group, A. bicornis was discovered only at a single locality on the southwest coast of North Island in 1983 on a fucoid seaweed and it may be relatively re-cently self-introduced. A specimen of A. lendigera (Linnaeus) in the Museum of New Zealand, purportedly from Napier, is considered to be based on a misunderstanding or a labelling error and does not represent a failed alien introduction. The Amathia-like vesiculariid Bowerbankia citrina (Hincks) sensu lato is newly recorded for New Zealand. Keys are provided to the amathiiform (i.e. Amathia and Amathia-like) Ctenostomata of New Zealand and to the worldwide species of Amathia and Bowerbankia with zooid clusters spiralled on stoloniform axes.