Phoronidea From the Pacific Coast of North America

Marsden, Joan R.

doi:10.1139/z59-012

Cited by 21 publications

(24 citation statements)

References 2 publications

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“…Two taxa presented particular taxonomic problems. The difficult differentiation of P. architecta (from the west coast of North America) and P. psammophila (from Europe) has been reported (Marsden, 1959), and the former has been described as a junior synonym of P. psammophila (Emig, 1982). This assessment is currently reflected in the GenBank taxonomy records for accessions derived from specimens collected in Florida as ‘ Phoronis architecta ’ by the Gulf Specimen Supply Company.…”

Section: Methodsmentioning

confidence: 99%

“…and Phoronopsis ( Ph. ) (Marsden, 1959; Emig, 1979, 1982, and references therein). Most phoronid embryos form long‐lived, planktotrophic (actinotroch) larvae that settle and undergo a distinctive metamorphosis (Herrmann, 1979; Santagata, 2002).…”

Section: Introductionmentioning

confidence: 99%

“…Until recently, relationships amongst phoronids had been inferred only from morphology (Marsden, 1959; Emig, 1974, 1979, 1982, 1985) and by analyses of SSU rDNA sequences from a limited taxon sample (Cohen et al. , 1998; Cohen, 2000), but a cladistic analysis of morphological characters and another phylogenetic reconstruction based on SSU rDNAs have recently appeared (Grobe, 2008).…”

Section: Introductionmentioning

confidence: 99%

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Phoronid phylogenetics (Brachiopoda; Phoronata): evidence from morphological cladistics, small and large subunit rDNA sequences, and mitochondrialcox1

Santagata¹,

Cohen²

2009

Zoological Journal of the Linnean Society

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A matrix of 24 morphodevelopmental characters and an alignment of small subunit (SSU) and large subunit (LSU) rDNA nuclear and cox1 mitochondrial gene sequences (~4500 sites) were compiled from up to 12 phoronids including most named taxa, but probably constituting only a portion of worldwide diversity. Morphological data were analysed by weighted parsimony; sequence data by maximum and Bayesian likelihood, both with Phoronis ovalis as the local outgroup. Morphological and sequence-based phylogenies were similar, but not fully congruent. Phoronid rDNAs were almost free from mutational saturation, but cox1 showed strong saturation unless distant outgroups and P. ovalis were omitted, suggesting that many phoronid divergences are old (Ն100 Myr). rDNA divergence between named phoronid taxa is generally substantial, but Phoronopsis harmeri (from Vladivostock) and Phoronopsis viridis (from California) are genetically close enough to be conspecific. In another alignment, of 24 taxa, phoronid rDNAs were combined with data from brachiopods and distant (molluscan) outgroups. The relative ages of divergence between phoronids and their brachiopod sister-groups, of the split between the P. ovalis and non-ovalis lineages, and of other phoronid splits, were estimated from this alignment with a Bayesian lognormal uncorrelated molecular clock model. Although confidence limits (95% highest probability density) are wide, the results are compatible with an Early Cambrian split between phoronids and brachiopods and with the Upper Devonian latest age suggested for the P. ovalis/non-ovalis split by the putative phoronid ichnofossil, Talpina. Most other ingroup splits appear to be~50-200 Myr old. Inclusion of phoronids with brachiopods in the crown clade pan-Brachiopoda suggests that a distinctive metamorphosis and absence of mineralization are ancestral phoronid apomorphies. Worldwide diversity and possible associations between character-states and life-history attributes deserve comprehensive further study.

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Section: Methodsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

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Phoronid phylogenetics (Brachiopoda; Phoronata): evidence from morphological cladistics, small and large subunit rDNA sequences, and mitochondrialcox1

Santagata¹,

Cohen²

2009

Zoological Journal of the Linnean Society

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“…Phoronis emigi differs from Phoronis psammophila in the number of longitudinal muscle bundles in the body wall (56–72 vs. 25–50 in Phoronis psammophila ) and the position of the right nephridiopores (at the same level as the anus vs. lower than the anus in Phoronis psammophila ) (cf. Andrews 1890, Selys-Longchamps 1907, Marsden 1959, Long 1960, Emig 1968, 1971b, 1979). …”

Section: Taxonomymentioning

confidence: 99%

Description and molecular phylogeny of a new species of Phoronis (Phoronida) from Japan, with a redescription of topotypes of P. ijimai Oka, 1897

Hirose¹,

Fukiage²,

Katoh³

et al. 2014

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We describe Phoronis emigi sp. n. as the eighth member of the genus based on specimens collected from a sandy bottom at 33.2 m depth in Tomioka Bay, Amakusa, Japan. The new species is morphologically similar to P. psammophila Cori, 1889, but can be distinguished from the latter by the number of longitudinal muscle bundles in the body wall (56–72 vs. 25–50 in P. psammophila) and the position of the nephridiopores (situated level with the anus vs. lower than the anus in P. psammophila). Using sequences of the nuclear 18S and 28S rRNA genes and the mitochondrial cytochrome c oxidase subunit I (COI) gene, we inferred the relationship of P. emigi to other phoronids by the maximum likelihood method and Bayesian analysis. The analyses showed that P. emigi is closely related to P. hippocrepia Wright, 1856 and P. psammophila Cori, 1889. We describe the morphology of the topotypes and additional material for P. ijimai Oka, 1897. Neither our morphological observations of P. ijimai, nor the phylogenetic analyses based on 18S and COI sequences, contradicts that P. vancouverensis Pixell, 1912 is conspecific with P. ijimai, a synonymy that has long been disputed.

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“…In Bodega Harbor, and other bays in California, the phoronid studied has been called Phoronopsis viridis (Hilton 1930); it has been synonymized with P. harmeri (Pixell 1912) by Marsden (1959). Although currently considered the same species, the relationship appears uncertain; here we use the name P. viridis in the case that the northeastern Pacific populations are indeed distinct from the more cosmopolitan P. harmeri.…”

Section: Methodsmentioning

confidence: 99%

Chemical defense of a soft-sediment dwelling phoronid against local epibenthic predators

Larson¹,

Stachowicz²

2009

Mar. Ecol. Prog. Ser.

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Chemical defenses are thought to be infrequent in most soft-sediment systems because organisms that live beneath the sediment rely more on avoidance or escape to reduce predation. However, selection for chemical deterrence might be strong among soft-sediment organisms that are sessile and expose at least part of their body above the surface. The phoronid Phoronopsis viridis is a tube-dwelling lophophorate that reaches high densities (26 500 m -2 ) on tidal flats in small bays in California, USA. We found that P. viridis is broadly unpalatable, and that this unpalatability is most apparent in the anterior section, including the lophophore, which is exposed to epibenthic predators as phoronids feed. Experimental removal of lophophores in the field increased the palatability of phoronids to predators; deterrence was regained after 12 d, when the lophophores had regenerated. Extracts of P. viridis deterred both fish and crab predators. Bioassay-guided fractionation suggested that the active compounds are relatively non-polar and volatile. Although we were unable to isolate the deterrent metabolite(s), we were able to rule out brominated phenols, a group of compounds commonly reported from infaunal organisms. One predator, juvenile Scorpaenichthys marmoratus, consumed all P. viridis extracts and whole P. viridis. However, over time, this predator rejected phoronids when fed a diet that included 2 to 3 phoronids d -1. The broadly effective defenses possessed by phoronids, which may be unusual among soft-sediment invertebrates, may play a key role in allowing them to reach high densities.

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Phoronidea From the Pacific Coast of North America

Cited by 21 publications

References 2 publications

Phoronid phylogenetics (Brachiopoda; Phoronata): evidence from morphological cladistics, small and large subunit rDNA sequences, and mitochondrialcox1

Phoronid phylogenetics (Brachiopoda; Phoronata): evidence from morphological cladistics, small and large subunit rDNA sequences, and mitochondrialcox1

Description and molecular phylogeny of a new species of Phoronis (Phoronida) from Japan, with a redescription of topotypes of P. ijimai Oka, 1897

Chemical defense of a soft-sediment dwelling phoronid against local epibenthic predators

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