Previous descriptions of members of Fabricia oregonica Banse, 1956, have distinguished it by the ... more Previous descriptions of members of Fabricia oregonica Banse, 1956, have distinguished it by the presence of only narrowly hooded inferior thoracic notochaetae, in contrast to the presence of pseudospatulate chaetae in median chaetigers of the type species, F. stellaris (Müller, 1774). In other respects, past descriptions of specimens to which F. oregonica refers have lacked the necessary detail to clearly determine generic placement, and the type material is in poor condition. Recently collected specimens matching earlier descriptions are used to redescribe members of the species. An exclusive sister-group relationship does not exist between F. stellaris and F. oregonica, precluding the latter species being assigned to Fabricia. Fabricia oregonica is therefore placed in a new genus, Bansella. Under the view that all taxa, whether phylogenetic or specific, are explanatory hypotheses, it is pointed out that the monotypic Bansella cannot be defined as such a hypothesis. While the Inte...
A new species of Fabricinuda Fitzhugh, F. longilabrum, is described from 60 to 70 m depth from th... more A new species of Fabricinuda Fitzhugh, F. longilabrum, is described from 60 to 70 m depth from the Gulf of Thailand, increasing the number of described species to six. Fabricinuda longilabrum most closely resembles F. pseudopalpa Fitzhugh in that both have well-developed branchial crown dorsal lips, but lack vascularized, ventral filamentous appendages. Remaining species in Fabricinuda do not have dorsal lips but do have filamentous appendages. Two new species of Pseudofabriciola Fitzhugh are also described. Pseudofabriciola filaris is from 60 to 70 m depth from the Gulf of Thailand, and P. rousei is from the intertidal along Western Australia, raising the number of described species in the genus to 13. Both species have only a single pair of dorsolateral notches on the anterior peristomial ring collar, reduced dorsal lips, and no vascularized, ventral filamentous appendages. Variation in collar form and overall body dimensions are discussed for P. filaris. The description of P. australiensis (Hartmann-Schröder), originally based on type specimens lacking a branchial crown, is emended on the basis of a complete specimen from Western Australia. The species has welldeveloped dorsal lips and vascularized, ventral filamentous appendages. Cladistic relationships among species within Fabricinuda and Pseudofabriciola are examined.
The fabriciin sabellid species, Fabricia brunnea Hartman, 1969, from central California, is assig... more The fabriciin sabellid species, Fabricia brunnea Hartman, 1969, from central California, is assigned to the genus Novafabricia Fitzhugh, 1990, based on information provided by recently collected specimens. In particular, thoracic notosetal pseudospatulate setae were found to be limited to setigers 3-5, a feature not ascertainable from the type series. Support for this change comes from a cladistic analysis involving N. brunnea and other Fabriciinae genera and species. The number of Novafabricia species is raised to at least seven. As part of this analysis, the status and relationships of the monotypic genus, Pseudo fabricia Cantone, 1972 (type species P. aberrans), Novafabricia bilobata Martin and Giangrande, 1991, and Augeneriella alata Hartmann-Schroder, 1991, are evaluated. Based on the original description, A. alata is a member of the undescribed taxon "Genus A" (sensu Fitzhugh, 1989). Results of the analysis support the recognition of Pseudofabricia and the generic placement of N. bilobata. Cladistic relationships among the seven species of Novafabricia, including N. brunnea, are analyzed and discussed. A key to Novafabricia species is provided.
Fitzhugh, K. 2014. Character mapping and cladogram comparison versus the requirement of total evi... more Fitzhugh, K. 2014. Character mapping and cladogram comparison versus the requirement of total evidence: does it matter for polychaete systematics? Memoirs of Museum Victoria 71: 67-78. The practice of partitioning data for the inferences of phylogenetic hypotheses has become a routine practice in biological systematics. Two popular approaches: (i) mapping 'morphological' characters onto 'molecular' phylogenies, and (ii) comparing 'morphological' and 'molecular' phylogenies, are examined in light of what is known as the requirement of total evidence. Inferences of phylogenetic hypotheses, indeed all taxa, occur by a type of non-deductive reasoning known as abduction. The intent of abduction is to offer at least tentative causal accounts that explain character data. The rational acceptance of abductively derived hypotheses is subject to conditions of the requirement of total evidence as a matter of the evidential support for those hypotheses. It is shown that both character mapping and comparisons of cladograms using partitioned datasets are procedures that severely reduce the credibility of phylogenetic hypotheses. This problem is alleviated by acknowledging the formal structure of the why-questions we ask in relation to character data, for which phylogenetic hypotheses serve as answers.
Key to the species of<i> Levinsenia</i> reported from California 1. 1A. Body very sma... more Key to the species of<i> Levinsenia</i> reported from California 1. 1A. Body very small ( 10–15 mm long, 0.10 mm wide), terminal sensory organ well developed, 4–8 pairs of truncate, heavily ciliated branchiae, acicular spines bent tipped with thick hoods....................................<i> L. barwicki</i><b> n. sp.</b> 1B. Body small to moderate size ( 15–30 mm long, 0.15-0.35 mm wide), terminal sensory organ not well developed, 5–36 branchial pairs, acicular spines not bent tipped, with fringe on convex side................................................ 2 2. 2A. Posterior acicular neurochaetae in multiple overlapping rows; vary in shape from longer, thinner, straighter to shorter, thicker more recurved; post-branchial notopodial with methyl green staining spots.........................<i> L. kirbyorum</i> 2B. Posterior acicular neurochaetae in single rows, uniformly shaped; post-branchial notopodia without methyl green staining s...
In 1989, Donald Reish hosted the 3rd International Polychaete Conference (IPC3) in Long Beach, on... more In 1989, Donald Reish hosted the 3rd International Polychaete Conference (IPC3) in Long Beach, on the campus of California State University Long Beach. In 2015 he asked one of us (Bruno Pernet) if it might be possible to bring IPC13 back to Long Beach, thirty years later. Bruno assembled a planning committee consisting of himself and Christine Whitcraft (CSU Long Beach), Kirk Fitzhugh and Leslie Harris (Natural History Museum of Los Angeles County), and Larry Lovell (Dancing Coyote Environmental). The committee’s proposal was accepted at the International Polychaetology Association (IPA) general meeting in Wales in 2016, and the planning committee morphed into an organizational committee!
Maldanids are tube-building polychaetes, known as bamboo-worms; inhabit diverse marine regions th... more Maldanids are tube-building polychaetes, known as bamboo-worms; inhabit diverse marine regions throughout the world. The subfamily Euclymeninae was proposed to include forms with anal and cephalic plates, a funnel-shaped pygidium, and a terminal anus. Euclymene, the type genus of Euclymeninae, has about 18 valid species. Euclymene vidali sp. nov. is defined and members of the species described from Northeastern Brazil. Members of this species have 23 chaetigers, and one pre-pygidial achaetous segment; nuchal grooves extend through three quarters of the cephalic plate, and there is one acicular spine with a denticulate tip. Euclymene africana, and E. watsoni, are here recognized, respectively, as Isocirrus africana comb. nov., and I. watsoni comb. nov. Three monotypic genera are invalid: Macroclymenella, Eupraxillella, and Pseudoclyemene; their species should be recognized as Clymenella stewartensis com. nov., Praxillella antarctica com. nov., and Praxillela quadrilobata com. nov., respectively. An identification key and a comparative table for all species of Euclymene are provided. A comparative table for all genera of Euclymeninae is also furnished. The paraphyletic status of Euclymene and Euclymeninae is discussed. The taxon Maldanoplaca is not code compliant and should only be regarded as an informal name.
Crother and Murray (Cladistics 31: 573–574, 2015) criticize the statement by Assis (Cladistics 30... more Crother and Murray (Cladistics 31: 573–574, 2015) criticize the statement by Assis (Cladistics 30: 240–242, 2014) that phylogenetic hypotheses are amenable to testing but not falsification. The claims by both sets of authors are based on long-standing misconceptions about testing developed within systematics. Testing phylogenetic hypotheses confuses the inferences of those hypotheses by way of abductive reasoning with their being tested via induction. Cladograms lack the causal details of the different hypotheses implied by those diagrams to make testing feasible, and falsification has been shown to be problematic for historical sciences.
Definitions offer meanings of words by way of associations with other terms [2, 3]. Accord‐ ingly... more Definitions offer meanings of words by way of associations with other terms [2, 3]. Accord‐ ingly, a definition relates a concept to a name [4]. Like any field of science, precision of communication in biology is dependent upon the use of terms, while actions taken as conse‐ quences of the acceptance of those terms are constrained by definitions. The importance of the meanings of words is especially critical when actions in one subfield of biology are dependent on terms developed in other subfields. A case in point involves the terms species, biodiversity, and conservation. With a voluminous literature regarding what species are supposed to be, the topic has suffered from an overemphasis on ‘species concepts’ that are largely detached from more inclusive biological systematics principles (e.g. [5]) required to answer the question ‘What is a species?’ While upwards of 26 species ‘concepts’ are recognized [6‒8], there is inconsistency among these in that they either refer to causal or...
Among portrayals of evolutionary biology and intelligent design, some evolutionary biologists and... more Among portrayals of evolutionary biology and intelligent design, some evolutionary biologists and organizations have claimed religion and science are compatible, commonly referred to as 'accommodationism.' This claim is, from the perspective of science, wholly incorrect. While religion and science are similar in that both seek causal explanations for natural phenomena, this does not render the two approaches compatible or not in conflict. The sciences seek causal understanding by way of theories and hypotheses that ensure understanding is open to critical, empirical evaluation. Reliance on supernatural-based theories and hypotheses are operationally immune to such testing. For religion and science to exist in a complimentary state, religious theories and hypotheses would have to be limited to explaining non-empirical, supernatural phenomena, while scientific theories and hypotheses are applied to natural phenomena. The opportunity for asymmetrical causal overlap is obviated, thus denying the accommodationist position.
Ernst Mayr's (1961, Science 131: 1501-1506) distinction between proximate and ultimate causation ... more Ernst Mayr's (1961, Science 131: 1501-1506) distinction between proximate and ultimate causation in biology is examined with regard to the acquisition of understanding in biological systematics. Rather than a two-part distinction, understanding in systematics is characterized by relations between three explanatory components: descriptive (observation statements)-proximate (ontogenetic hypotheses)-ultimate (e.g. specific and phylogenetic hypotheses). Initial inferential actions in each component involve reasoning to explanatory hypotheses via abductive inference, providing preliminary understanding. Testing hypotheses, to critically assess understanding, is varied. Descriptive-and proximate-level hypotheses are routinely tested, but ultimate hypotheses present inherent difficulties that impose severe limits, contrary to what is usually claimed in the systematics literature. The problem is compounded by imprecise considerations of 'evidence' and 'support.' For instance, in most cases, the 'evidence' offering 'support' for phylogenetic hypotheses, as cladograms, is nothing more than the abductive evidence (premises) used to infer those hypotheses, i.e. character data and associated phylogenetic-based theories. By definition, such evidence only offers initial, trivial understanding, whereas the pertinent evidence sought in the sciences is test evidence, which cannot be supplanted by character data. The pursuit of ultimate understanding by way of spurious procedures such as contrived testing, Bremer support, and resampling methods are discussed with regard to phylogenetic hypotheses.
Known as shovel head worms, members of Magelonidae comprise a group of polychaetes readily recogn... more Known as shovel head worms, members of Magelonidae comprise a group of polychaetes readily recognised by the uniquely shaped, dorso-ventrally flattened prostomium and paired ventro-laterally inserted papillated palps. The present study is the first published account of inferences of phylogenetic hypotheses within Magelonidae. Members of 72 species of Magelona and two species of Octomagelona were included, with outgroups including members of one species of Chaetopteridae and four of Spionidae. The phylogenetic inferences were performed to causally account for 176 characters distributed among 79 subjects, and produced 2,417,600 cladograms, each with 404 steps. A formal definition of Magelonidae is provided, represented by a composite phylogenetic hypothesis explaining seven synapomorphies: shovel-shaped prostomium, prostomial ridges, absence of nuchal organs, ventral insertion of palps and their papillation, presence of a burrowing organ, and unique body regionation. Octomagelona is s...
Previous descriptions of members of Fabricia oregonica Banse, 1956, have distinguished it by the ... more Previous descriptions of members of Fabricia oregonica Banse, 1956, have distinguished it by the presence of only narrowly hooded inferior thoracic notochaetae, in contrast to the presence of pseudospatulate chaetae in median chaetigers of the type species, F. stellaris (Müller, 1774). In other respects, past descriptions of specimens to which F. oregonica refers have lacked the necessary detail to clearly determine generic placement, and the type material is in poor condition. Recently collected specimens matching earlier descriptions are used to redescribe members of the species. An exclusive sister-group relationship does not exist between F. stellaris and F. oregonica, precluding the latter species being assigned to Fabricia. Fabricia oregonica is therefore placed in a new genus, Bansella. Under the view that all taxa, whether phylogenetic or specific, are explanatory hypotheses, it is pointed out that the monotypic Bansella cannot be defined as such a hypothesis. While the Inte...
A new species of Fabricinuda Fitzhugh, F. longilabrum, is described from 60 to 70 m depth from th... more A new species of Fabricinuda Fitzhugh, F. longilabrum, is described from 60 to 70 m depth from the Gulf of Thailand, increasing the number of described species to six. Fabricinuda longilabrum most closely resembles F. pseudopalpa Fitzhugh in that both have well-developed branchial crown dorsal lips, but lack vascularized, ventral filamentous appendages. Remaining species in Fabricinuda do not have dorsal lips but do have filamentous appendages. Two new species of Pseudofabriciola Fitzhugh are also described. Pseudofabriciola filaris is from 60 to 70 m depth from the Gulf of Thailand, and P. rousei is from the intertidal along Western Australia, raising the number of described species in the genus to 13. Both species have only a single pair of dorsolateral notches on the anterior peristomial ring collar, reduced dorsal lips, and no vascularized, ventral filamentous appendages. Variation in collar form and overall body dimensions are discussed for P. filaris. The description of P. australiensis (Hartmann-Schröder), originally based on type specimens lacking a branchial crown, is emended on the basis of a complete specimen from Western Australia. The species has welldeveloped dorsal lips and vascularized, ventral filamentous appendages. Cladistic relationships among species within Fabricinuda and Pseudofabriciola are examined.
The fabriciin sabellid species, Fabricia brunnea Hartman, 1969, from central California, is assig... more The fabriciin sabellid species, Fabricia brunnea Hartman, 1969, from central California, is assigned to the genus Novafabricia Fitzhugh, 1990, based on information provided by recently collected specimens. In particular, thoracic notosetal pseudospatulate setae were found to be limited to setigers 3-5, a feature not ascertainable from the type series. Support for this change comes from a cladistic analysis involving N. brunnea and other Fabriciinae genera and species. The number of Novafabricia species is raised to at least seven. As part of this analysis, the status and relationships of the monotypic genus, Pseudo fabricia Cantone, 1972 (type species P. aberrans), Novafabricia bilobata Martin and Giangrande, 1991, and Augeneriella alata Hartmann-Schroder, 1991, are evaluated. Based on the original description, A. alata is a member of the undescribed taxon "Genus A" (sensu Fitzhugh, 1989). Results of the analysis support the recognition of Pseudofabricia and the generic placement of N. bilobata. Cladistic relationships among the seven species of Novafabricia, including N. brunnea, are analyzed and discussed. A key to Novafabricia species is provided.
Fitzhugh, K. 2014. Character mapping and cladogram comparison versus the requirement of total evi... more Fitzhugh, K. 2014. Character mapping and cladogram comparison versus the requirement of total evidence: does it matter for polychaete systematics? Memoirs of Museum Victoria 71: 67-78. The practice of partitioning data for the inferences of phylogenetic hypotheses has become a routine practice in biological systematics. Two popular approaches: (i) mapping 'morphological' characters onto 'molecular' phylogenies, and (ii) comparing 'morphological' and 'molecular' phylogenies, are examined in light of what is known as the requirement of total evidence. Inferences of phylogenetic hypotheses, indeed all taxa, occur by a type of non-deductive reasoning known as abduction. The intent of abduction is to offer at least tentative causal accounts that explain character data. The rational acceptance of abductively derived hypotheses is subject to conditions of the requirement of total evidence as a matter of the evidential support for those hypotheses. It is shown that both character mapping and comparisons of cladograms using partitioned datasets are procedures that severely reduce the credibility of phylogenetic hypotheses. This problem is alleviated by acknowledging the formal structure of the why-questions we ask in relation to character data, for which phylogenetic hypotheses serve as answers.
Key to the species of<i> Levinsenia</i> reported from California 1. 1A. Body very sma... more Key to the species of<i> Levinsenia</i> reported from California 1. 1A. Body very small ( 10–15 mm long, 0.10 mm wide), terminal sensory organ well developed, 4–8 pairs of truncate, heavily ciliated branchiae, acicular spines bent tipped with thick hoods....................................<i> L. barwicki</i><b> n. sp.</b> 1B. Body small to moderate size ( 15–30 mm long, 0.15-0.35 mm wide), terminal sensory organ not well developed, 5–36 branchial pairs, acicular spines not bent tipped, with fringe on convex side................................................ 2 2. 2A. Posterior acicular neurochaetae in multiple overlapping rows; vary in shape from longer, thinner, straighter to shorter, thicker more recurved; post-branchial notopodial with methyl green staining spots.........................<i> L. kirbyorum</i> 2B. Posterior acicular neurochaetae in single rows, uniformly shaped; post-branchial notopodia without methyl green staining s...
In 1989, Donald Reish hosted the 3rd International Polychaete Conference (IPC3) in Long Beach, on... more In 1989, Donald Reish hosted the 3rd International Polychaete Conference (IPC3) in Long Beach, on the campus of California State University Long Beach. In 2015 he asked one of us (Bruno Pernet) if it might be possible to bring IPC13 back to Long Beach, thirty years later. Bruno assembled a planning committee consisting of himself and Christine Whitcraft (CSU Long Beach), Kirk Fitzhugh and Leslie Harris (Natural History Museum of Los Angeles County), and Larry Lovell (Dancing Coyote Environmental). The committee’s proposal was accepted at the International Polychaetology Association (IPA) general meeting in Wales in 2016, and the planning committee morphed into an organizational committee!
Maldanids are tube-building polychaetes, known as bamboo-worms; inhabit diverse marine regions th... more Maldanids are tube-building polychaetes, known as bamboo-worms; inhabit diverse marine regions throughout the world. The subfamily Euclymeninae was proposed to include forms with anal and cephalic plates, a funnel-shaped pygidium, and a terminal anus. Euclymene, the type genus of Euclymeninae, has about 18 valid species. Euclymene vidali sp. nov. is defined and members of the species described from Northeastern Brazil. Members of this species have 23 chaetigers, and one pre-pygidial achaetous segment; nuchal grooves extend through three quarters of the cephalic plate, and there is one acicular spine with a denticulate tip. Euclymene africana, and E. watsoni, are here recognized, respectively, as Isocirrus africana comb. nov., and I. watsoni comb. nov. Three monotypic genera are invalid: Macroclymenella, Eupraxillella, and Pseudoclyemene; their species should be recognized as Clymenella stewartensis com. nov., Praxillella antarctica com. nov., and Praxillela quadrilobata com. nov., respectively. An identification key and a comparative table for all species of Euclymene are provided. A comparative table for all genera of Euclymeninae is also furnished. The paraphyletic status of Euclymene and Euclymeninae is discussed. The taxon Maldanoplaca is not code compliant and should only be regarded as an informal name.
Crother and Murray (Cladistics 31: 573–574, 2015) criticize the statement by Assis (Cladistics 30... more Crother and Murray (Cladistics 31: 573–574, 2015) criticize the statement by Assis (Cladistics 30: 240–242, 2014) that phylogenetic hypotheses are amenable to testing but not falsification. The claims by both sets of authors are based on long-standing misconceptions about testing developed within systematics. Testing phylogenetic hypotheses confuses the inferences of those hypotheses by way of abductive reasoning with their being tested via induction. Cladograms lack the causal details of the different hypotheses implied by those diagrams to make testing feasible, and falsification has been shown to be problematic for historical sciences.
Definitions offer meanings of words by way of associations with other terms [2, 3]. Accord‐ ingly... more Definitions offer meanings of words by way of associations with other terms [2, 3]. Accord‐ ingly, a definition relates a concept to a name [4]. Like any field of science, precision of communication in biology is dependent upon the use of terms, while actions taken as conse‐ quences of the acceptance of those terms are constrained by definitions. The importance of the meanings of words is especially critical when actions in one subfield of biology are dependent on terms developed in other subfields. A case in point involves the terms species, biodiversity, and conservation. With a voluminous literature regarding what species are supposed to be, the topic has suffered from an overemphasis on ‘species concepts’ that are largely detached from more inclusive biological systematics principles (e.g. [5]) required to answer the question ‘What is a species?’ While upwards of 26 species ‘concepts’ are recognized [6‒8], there is inconsistency among these in that they either refer to causal or...
Among portrayals of evolutionary biology and intelligent design, some evolutionary biologists and... more Among portrayals of evolutionary biology and intelligent design, some evolutionary biologists and organizations have claimed religion and science are compatible, commonly referred to as 'accommodationism.' This claim is, from the perspective of science, wholly incorrect. While religion and science are similar in that both seek causal explanations for natural phenomena, this does not render the two approaches compatible or not in conflict. The sciences seek causal understanding by way of theories and hypotheses that ensure understanding is open to critical, empirical evaluation. Reliance on supernatural-based theories and hypotheses are operationally immune to such testing. For religion and science to exist in a complimentary state, religious theories and hypotheses would have to be limited to explaining non-empirical, supernatural phenomena, while scientific theories and hypotheses are applied to natural phenomena. The opportunity for asymmetrical causal overlap is obviated, thus denying the accommodationist position.
Ernst Mayr's (1961, Science 131: 1501-1506) distinction between proximate and ultimate causation ... more Ernst Mayr's (1961, Science 131: 1501-1506) distinction between proximate and ultimate causation in biology is examined with regard to the acquisition of understanding in biological systematics. Rather than a two-part distinction, understanding in systematics is characterized by relations between three explanatory components: descriptive (observation statements)-proximate (ontogenetic hypotheses)-ultimate (e.g. specific and phylogenetic hypotheses). Initial inferential actions in each component involve reasoning to explanatory hypotheses via abductive inference, providing preliminary understanding. Testing hypotheses, to critically assess understanding, is varied. Descriptive-and proximate-level hypotheses are routinely tested, but ultimate hypotheses present inherent difficulties that impose severe limits, contrary to what is usually claimed in the systematics literature. The problem is compounded by imprecise considerations of 'evidence' and 'support.' For instance, in most cases, the 'evidence' offering 'support' for phylogenetic hypotheses, as cladograms, is nothing more than the abductive evidence (premises) used to infer those hypotheses, i.e. character data and associated phylogenetic-based theories. By definition, such evidence only offers initial, trivial understanding, whereas the pertinent evidence sought in the sciences is test evidence, which cannot be supplanted by character data. The pursuit of ultimate understanding by way of spurious procedures such as contrived testing, Bremer support, and resampling methods are discussed with regard to phylogenetic hypotheses.
Known as shovel head worms, members of Magelonidae comprise a group of polychaetes readily recogn... more Known as shovel head worms, members of Magelonidae comprise a group of polychaetes readily recognised by the uniquely shaped, dorso-ventrally flattened prostomium and paired ventro-laterally inserted papillated palps. The present study is the first published account of inferences of phylogenetic hypotheses within Magelonidae. Members of 72 species of Magelona and two species of Octomagelona were included, with outgroups including members of one species of Chaetopteridae and four of Spionidae. The phylogenetic inferences were performed to causally account for 176 characters distributed among 79 subjects, and produced 2,417,600 cladograms, each with 404 steps. A formal definition of Magelonidae is provided, represented by a composite phylogenetic hypothesis explaining seven synapomorphies: shovel-shaped prostomium, prostomial ridges, absence of nuchal organs, ventral insertion of palps and their papillation, presence of a burrowing organ, and unique body regionation. Octomagelona is s...
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