Species Of Cheilostome Bryozoans Research Articles

Encrusting bryozoan attached to terrestrial plant leaves from brackish deposits of the Lefipán Formation (Patagonia, Argentina), close to the K/Pg boundary

Cretaceous bryozoans from South America have received limited attention despite their sporadic documentation. The K/Pg boundary has been identified in numerous fossil-rich basins in Patagonia, where bryozoans are frequent components of the faunas. Material recovered from upper Maastrichtian outcrops of the Lefipán Formation in the Cañadón Asfalto Basin (Patagonia, Argentina) includes a unique species of cheilostome bryozoan, Conopeum foliorum n. sp., attached to leaf remains of terrestrial plants and associated with scarce euryhaline bivalves. It likely thrived in a warm climate, shallow, well-lit brackish environment influenced by tides, located along the northwest margin of the Paso del Sapo embayment. Conopeum foliorum n. sp. is currently among the earliest known bryozoans from brackish water environments, and the second oldest documented instance of a bryozoan encrusting leaves of terrestrial plants, representing the first of such finding in South America. Based on our findings and available sedimentological and paleoecological data from previous studies, we interpreted Conopeum foliorum n. sp. as a fast-growing opportunistic taxon displaying euryhaline habits and prone to colonize terrestrial plant leaves deposited in a brackish-water nearshore environment.

One new genus and five new species of deep-sea bryozoans from the subantarctic Southwest Atlantic

In this study we introduce one new genus and five new species of cheilostome bryozoans based on material collected mainly at bathyal depths in the Subantarctic Southwest Atlantic by the vessels ARA Bahía Blanca, BO Puerto Deseado and RV Meteor. Bathyanasca incubatrix gen. nov., sp. nov., Chondriovelum perforatum sp. nov., Aspidostoma adeoniforme sp. nov., Talivittaticella bathyalis sp. nov. and Turritigera formidabilis sp. nov. are described and illustrated. Bathyanasca incubatrix, characterized by the lack of ovicells and the incubation of embryos within the autozooidal cavity, is tentatively classified in the family Calloporidae. Present results contribute to support the hypothesis of close faunal affinities between Antarctica and relatively deep areas around southern South America.

Scanning electron microscopy study of Lars Silns cheilostome bryozoan type specimens in the historical collections of natural history museums in Sweden.

The type specimens of 42 cheilostome bryozoan species introduced by Lars Siln between 1938 and 1954 and housed at three different Swedish institutions (the Swedish Museum of Natural History in Stockholm, the Biological Museum in Lund and the Museum of Evolution in Uppsala) are here revised using scanning electron microscopy, with two exceptions, for the first time. As a result of this revision, new morphological observations were made for some species, such as ooecia in Antropora erecta, a costal pseudopore in Jullienula hippocrepis, intracolonial variation in the number of intracostal windows in Costaticella gisleni, and oral spines in Triphyllozoon mauritzoni. Some other observations confirmed the presence of structures/polymorphs in type material that had previously only been noted in non-type specimens, such as spinose interzooidal kenozooids in Retevirgula triangulata and putative brooding zooids in Bugulina kiuschiuensis. Structures originally interpreted as hydroid tube openings on the dorsal side of Triphyllozoon microstigmatum were confirmed to be avicularia, while the supposed kenozooidal attachment rootlet of Fedora nodosa might be the polypide tube of a coronate scyphozoan. In addition, the original combination Heliodoma goesi is here reinstated after Lagaaij assigned the species to Setosellina in 1963. The following new combinations are also proposed: Labioporella aviculifera for Siphonoporella aviculifera; Mangana canui and Mangana incrustata for Callopora canui and Tegella incrustata, respectively; Sphaerulobryozoon ovum for Fedora ovum. Lectotypes were selected when appropriate. This work clarifies the exact identity of some species that have never been recorded after their first description, such as Stylopoma magnovicellata and three species of Triphyllozoon, and contributes to the current increasing effort to digitize historical key specimens in natural history museum collections.

Enhancing georeferenced biodiversity inventories: automated information extraction from literature records reveal the gaps.

We use natural language processing (NLP) to retrieve location data for cheilostome bryozoan species (text-mined occurrences (TMO)) in an automated procedure. We compare these results with data combined from two major public databases (DB): the Ocean Biodiversity Information System (OBIS), and the Global Biodiversity Information Facility (GBIF). Using DB and TMO data separately and in combination, we present latitudinal species richness curves using standard estimators (Chao2 and the Jackknife) and range-through approaches. Our combined DB and TMO species richness curves quantitatively document a bimodal global latitudinal diversity gradient for extant cheilostomes for the first time, with peaks in the temperate zones. A total of 79% of the georeferenced species we retrieved from TMO (N = 1,408) and DB (N = 4,549) are non-overlapping. Despite clear indications that global location data compiled for cheilostomes should be improved with concerted effort, our study supports the view that many marine latitudinal species richness patterns deviate from the canonical latitudinal diversity gradient (LDG). Moreover, combining online biodiversity databases with automated information retrieval from the published literature is a promising avenue for expanding taxon-location datasets.

Bryozoans Associated with Gastropod Shells in the Early Miocene of Patagonia (Argentina)

This study describes two new species of cheilostome bryozoans associated with gastropod shells from the Monte León Formation (Burdigalian, early Miocene), Argentine Patagonia. Burdwoodipora griffini sp. nov. is the second known species and the first fossil representative of the genus, whose geographic distribution is so far restricted to the Magellan region in the southern Southwest Atlantic. It differs from the type species, B. paguricola, in lacking suboral adventitious avicularia in most autozooids. Odontoporella miocenica sp. nov. is morphologically very close to the type species, the Recent O. adpressa, from which it differs in having smaller zooids with fewer areolae and relatively wider orifices. The stratigraphic range of Odontoporella is here extended from the Pleistocene to the early Miocene. Its geographic distribution includes southern South America, New Zealand, and New Caledonia, suggesting an austral origin of the genus in the Paleogene of former Gondwana. The possible association of these two species with paguroid crabs is discussed.

Two new species of cheilostomate Bryozoa from Iberian waters

Two new species of cheilostomate bryozoans are described from material preserved in museums: Cradoscrupocellaria severoi sp. nov., from Iberian Mediterranean waters, and Setosella margaritae sp. nov., from shallow waters along the Atlantic coast of Europe. Moreover, the Mediterranean species Setosella cyclopensis Rosso, Di Martino & Gerovasileiou, 2020 is reported in Iberian waters for the first time.

Pleistocene Bryozoans from the Clyde Clay Formation of Scotland, and the Holocene Retreat of Cold-Water Species

Although bryozoans are a diverse phylum of aquatic invertebrates with a rich fossil record, very little has been written about bryozoan faunas from the latest Pleistocene at a time of rapid global change when temperatures increased dramatically and the sea-level rose. Two species of cyclostome and eight species of cheilostome bryozoans are here described from the late Devensian Clyde Clay Formation of Greenock, Scotland, based on historical material in the collections of the NHM, UK. All are illustrated for the first time from this deposit using scanning electron microscopy. Three of the species (Tubulipora cf. marisalbi, Rhamphostomella radiatula and Schizomavella porifera) are unknown from the seas around Scotland at the present-day but occur in colder waters to the north. This is consistent with the poleward retreat of cold-water species as seawater temperatures increased at the end of the Pleistocene.

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.

First record of an abyssal and hadal bryozoan fauna from the Kuril-Kamchatka Trench

Benthic samples collected during cruise SO250 of the RV Sonne along the Kuril-Kamchatka Trench from three abyssal stations, at depths of 5134–5478 m, and one hadal station, at depths of 7241–7245 m, yielded one ctenostome and three cheilostome bryozoan species. The species encountered represent the deepest records of each genus. The record of Aethozoon pellucidum is the first hadal and the deepest for any species in the order Ctenostomata, increasing the number of known hadal bryozoan species to five. Our records of Aethozoon pellucidum and Atlantisina pacifica sp. nov. are the first for these genera in the Pacific Ocean, and that of Smithsonius quadratus sp. nov. is the first record for the northwestern Pacific. Bathymetrically, the fauna is equally represented by widespread eurybathic and abyssal stenobathic elements. Colony morphology is atypically diverse for the deep-water environment and includes four different forms, with A. pellucidum and Kinetoskias mitsukuri living on soft bottoms, and A. pacifica and S. quadratus colonizing hard substrata. No species was found on biotic substrata. The low degree of biomineralization of zooids in K. mitsukuri and A. pacifica coupled with their large size may reflect the synergistic effects of the deep-sea phenomena ‘rachitism’ and ‘gigantism’.

Cheilostome Bryozoa of the northern Persian Gulf, Iran.

This paper describes 15 cheilostome bryozoan species obtained from 15 sampling sites along the northern coast of the Persian Gulf in Iran. Two of the cheilostomes are described as new species: Parasmittina cryptoavicularia n. sp. and Trematooecia persica n. sp. The majority of species found in this study (67%) have a tropical to subtropical Indo-Pacific distribution, while the remainder are more widely distributed. Several are fouling species known from warmer seas around the globe. Further sampling efforts are needed to obtain a better estimate of the true bryozoan diversity in the region which is almost certainly much greater than the 15 species described in this study.

Bryozoa on disarticulated bivalve shells from Todos os Santos Bay, northeastern Brazil, with the description of two new species.

As sessile organisms, bryozoans are among the commonest components of the encrusting communities on hard substrata. On unconsolidated bottoms, benthic animals and their carapaces, including mollusk shells, represent potential surfaces for encrustation. Here we describe the bryozoan fauna growing on disarticulated bivalve shells collected intertidally on Itaparica beach, Todos os Santos Bay, northeast Brazil. We examined a total of 382 valves representing seven species of bivalves, among which we found 82 valves of three bivalve species to be encrusted by bryozoans, with 109 bryozoan colonies detected overall. We identified 11 cheilostome bryozoan species, among which Phidoloporidae and Smittinidae were the most diverse, with four and two species, respectively. We redescribed two bryozoan species, Parasmittina loxoides and Rhynchozoon phrynoglossum, and describe another two, Pleurocodonellina marcusi n. sp. and Rhynchozoon itaparicaensis n. sp., as new. A new combination for Cribella triangulata Canu Bassler, 1928 is proposed, including Calyptotheca tenuata Harmer, 1957 as a new junior subjective synonym of Calyptotheca triangulata n. comb. All but one of the 11 species have encrusting colonies; Licornia aff. diadema, forms erect branching colonies. For seven of the bryozoans, ours are the first records of these species growing on shells. Although the majority of bryozoans we studied have also been reported on other substrata, Rhynchozoon brasiliensis and Parasmittina loxoides were predominant in the fauna, comprising 79 (72%) of all colonies inventoried. Due to the lack of information on the distribution of these species in northeastern Brazil, further studies are needed to determine whether they show any substratum preference.

New Cheilostomata (Bryozoa) species from sublittoral and bathyal zones off the Faroe Islands, with some comments on allied taxa.

Two new species of cheilostome Bryozoa are described from the Faroe Islands archipelago. Cinclidia aculeata n. gen. et sp. is a new cribrilinid taxon, distinguished from other cribrimorphs by the skeletal characters of the frontal shield and ooecium, and the absence of avicularia. A second new species, Turbicellepora faroensis n. sp., is distinguished by the shape of the orificial sinus, peristome, and suboral and interzooidal avicularia as well as by the presence of distolateral, tube-shaped adventitious avicularia (paired or single). Examination of new material of congeneric species supports the validity of the new taxon and further clarifies the separate status of Turbicellepora tuberosa (Smitt, 1868) sensu Hansen (1962) and T. hansenae Denisenko, 2016.

A new genus and species of cheilostome bryozoan associated with hermit crabs in the subantarctic Southwest Atlantic

Some bryozoan species occur on gastropod shells occupied by hermit crabs, often dominating the shell surface to the exclusion of other encrusters. Symbioses between bryozoans and pagurid crabs are known from a wide latitudinal range, including tropical, warm- and cold-temperate regions. Here we describe Burdwoodipora paguricola gen. et sp. nov., a cheilostome bryozoan associated with pagurized shells occupied by the hermit crab Pagurus comptus White in subantarctic waters of the Southwest Atlantic. The association seems to be obligate, as the bryozoan was always found enlarging the last whorl of its gastropod substrate. The new species, however, is not species specific with regard to its shell substrate, as it was found to be associated with 31 species of gastropods with helicoidal coiling. Well-developed colonies may project up to 360° from the outer lip of the shell. The chamber built by the bryozoan is usually larger than the whorl that would have been generated by the gastropod. This is one of the few known cases of an obligate association between a bryozoan and a pagurid crab outside the ascophoran family Hippoporidridae and is also the first bryozoan/hermit crab symbiosis documented in the subantarctic region. The inclusion of Burdwoodipora in the Pacificincolidae, a family currently represented by just four species from the Northern Hemisphere, is discussed.

Deep-water Bryozoa from the Kuril Basin, Sea of Okhotsk

Benthic samples collected at six stations in the Kuril Basin, Sea of Okhotsk, at depths of 3301 to 3366 m, and at two northwestern Pacific stations in Bussol Strait and on the western slope of the Kuril-Kamchatka Trench, at depths 2267 and 3374 m, yielded three cyclostome, two ctenostome, and two cheilostome bryozoan species. Among these, Oncousoecia viskovae sp. nov. is the deepest record for a species in this genus. Triticella maiorovae sp. nov., a symbiont on a sipunculid worm, is the second species of the genus discovered in the northwestern Pacific. Our study yielded the deepest records for Bicrisia abyssicola and Buchneria teres, and the first records for Triticella minini and B. teres from the Sea of Okhotsk. The proportion of cheilostomes in the samples was much lower than expected from previous studies, although the sample size and total diversity were also low. Dead colonies of four cheilostome species, Einhornia arctica, Porella alba, Cryptosula zavjalovensis and Cheilopora praelucida, were found encrusting pebbles at two abyssal sites; we interpret these as allochthonic elements due to ice transport of pebbles from shallow waters to the Kuril Basin. Stenobathic and eurybathic species common to both the Kuril Basin and northwestern Pacific indicate connectivity between deep water faunas in these adjacent regions.

Bryozoa of the southern Caspian Sea, Iranian coast

Bryozoans were found attached to various natural and artificial substrates at 18 sites along the Iranian coast of the southern Caspian Sea. Two species of cheilostome bryozoans—Conopeum grimmi and Lapidosella ostroumovi—and species of ctenostomes—Amathia gracilis and Victorella pavida—are reported. Lapidosella ostroumovi is a record for the Caspian Sea.

Diversity of marine bryozoans inhabiting demosponges in northeastern Brazil

As primary or obligate sessile organisms, bryozoans depend upon a substratum resource that affects their abundance, distribution and diversity. These animals can colonize virtually any type of substratum, including other organisms and artificial structures. Associations between bryozoans and sponges are commonly reported in the literature, but there are few studies discussing the association between these two taxa in detail. Here we present data on the bryozoan community found on shallow-water sponges from Bahia coast, northeastern Brazil, including their taxonomic status, colony form and adaptative structures utilized by these bryozoans to grow on sponges. Twenty-one bryozoan species were found attached to the surface of sixteen species of sponges. Five new species of cheilostome bryozoans are described. A total of 105 colonies were studied and most of them are erect delicate branching (44 colonies) and encrusting patches (34 colonies). The majority of bryozoan colonies were attached to the surface of rugose-textured sponges (67 colonies; 61%). This suggests that bryozoans are more likely to settle on irregular and rough surfaces. Patches colonies were mainly attached to the portion of the sponge that was in contact with the seabed, and spot colonies were particularly found in spatial refuges, showing the preference of larvae to settle on shaded and less exposed substrata. Most erect bryozoans were attached to the lateral sponge surface, other colonies grew on the underside and few on the upper surface of the sponges. These colonies were attached either using anchoring rhizoids, rigid bases, or stolons. The bryozoan species and genera reported here are common in northeastern Brazil and considered generalists in terms of larval settlement requirements. The bryozoan-sponge association studied is considered a non-obligatory commensalism (inquilinism).

Bryozoan diversity around the Falkland and South Georgia Islands: Overcoming Antarctic barriers

There are a number of remote archipelagos distributed between 45 and 60 °S. The biota of these islands provide useful information to describe and understand patterns in biodiversity and biogeography as well as potential impacts of climate change on marine ecosystems. They are in key locations either side of the Polar Front but also have limited influence from human activities. Here we investigate one taxon, bryozoans, on South Atlantic shelf habitats of the Falkland (FI) and the sub-Antarctic island of South Georgia (SG). We present new data on spatial distribution in these islands, as well as an analysis of the bryozoological similarities between these and neighbouring regions. A total of 85 species of cheilostome bryozoans (351 samples) were found, belonging to 33 genera, including 18 potentially new genera and 23 new species. Remarkably 65% and 41% of species were reported for the first time at FI and SG, respectively. The highest and the lowest value of species richness and species/genus ratio were found at East (EFI) and West Falkland (WFI), respectively, likely showing a tendency for stronger intrageneric competition. New data from this study were jointly analysed with data from the literature and existing databases, revealing new bathymetric ranges in 32 species. The biogeographic affinities of the bryozoans found give further evidence of the hypothesis of sequential separation of Gondwana and support the changing concept that although the Polar Front acts as a circumpolar biogeographic barrier it is not as impermeable as originally thought. Potential dispersal mechanisms are also discussed.

Cenomanian cheilostome bryozoans from Devon, England

The Cenomanian witnessed a spectacular evolutionary radiation of cheilostome bryozoans, both in terms of species diversity and morphological disparity. However, Cenomanian cheilostome faunas are inadequately known. Twelve species of cheilostome bryozoans are here described from the Cenomanian Beer Head Limestone Formation of SE Devon, England, a nearshore facies of limestones and sands. Two of the cheilostome species are new – Wilbertopora manubriformis sp. nov. and Foratella cervisia sp. nov. – and five cannot be identified beyond genus level. Syntypes of Foratella forata (d’Orbigny, 1853), the Senonian type species of Foratella Canu, 1900, are illustrated using SEM and a lectotype is chosen. All of the species present are neocheilostomes, which were larval brooders. Compared with the non-brooding malacostegans that dominate pre-Cenomanian faunas, most species have avicularia and extensive frontal walls, features probably adaptive against small predators.

Hexactinellid sponges reported from shallow waters in the Oligo-Miocene Pirabas Formation (N Brazil) are in fact cheilostome bryozoans

Although hexactinellid sponges occur exclusively in deep and/or cold waters, three species of hexactinellids have been reported from shallow and warm waters in Oligo-Miocene deposits of the Pirabas Formation in northern Brazil: Aphrocallistes estevoui, A. lobata and Manzonia aprutina. Here we re-examine these fossils and show that they are not hexactinellid sponges but instead comprise three species of cheilostome bryozoans of the genus Celleporaria (Family Lepraliellidae). Two of these are new to science, viz., Celleporaria pirabasensis sp. nov. and Celleporaria triangulavicularis sp. nov., and the third could not be identified to species level due to poor preservation. Colonies of all three species are massive and multilaminar, with irregular layers of zooids produced by frontal budding. Autozooids have marginal areolar pores and a rounded, asinuate primary orifice. All colonies also have suboral adventitious avicularia and interzooidal avicularia, although of different shapes and sizes. Celleporaria triangulavicularis sp. nov. has distinctive triangular interzooidal avicularia. The underside of the frontal shield was seen only in Celleporaria pirabasensis sp. nov. and Celleporaria sp., in which it is umbonuloid. Ovicells were only seen in Celleporaria pirabasensis sp. nov. and are cap-shaped. The three species differ among themselves mainly in the shape and position of the adventitious and interzooidal avicularia. The presence of several typical bryozoan traits and the absence of spicule traces or any other sponge features clearly demonstrate that these fossils are bryozoans, not sponges. The change in the classification of these fossils from hexactinellids to bryozoans of the genus Celleporaria eliminates the incongruence of the occurrence of deep-water species in the warm shallow water depositional environment of the Pirabas Formation.

Cheilostome Bryozoa from Penang and Langkawi, Malaysia

Twenty-three species of cheilostome bryozoans are described from the Malaysian islands of Penang and Langkawi based on a brief reconnaisance survey of shore localities. These are the first bryozoans to be formally described from either island and they demonstrate the potential for further research on these neglected suspension feeders. Of the 23 species recorded, 12 are anascans, half of which are malacostegines, and 11 are ascophorans. The new combinations Acanthodesia falsitenuis (Liu, 1992), A. perambulata (Louis & Menon, 2009) and A. irregulata (Liu, 1992) are introduced. Most of the species recorded are widespread in the Indo-Pacific, and some are apparently globally distributed in the tropics and subtropics, including the invasive fouling species Bugula neritina, Hippoporina indica and Schizoporella japonica, as well as the coral reef associates Cranosina coronata and Hippopodina feegeensis. Plastic debris and glass bottles were encrusted by Jellyella eburnea, a coloniser of floating biological and man-made objects that is becoming widespread in the tropics and subtropics of the world’s oceans.