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Gill A.C.,University of Sydney | Gill A.C.,College Street | Mooi R.D.,Manitoba Museum | Mooi R.D.,University of Manitoba
Zootaxa | Year: 2012

Thalasseleotrididae n. fam. is erected to include two marine genera, Thalasseleotris Hoese & Larson from temperate Australia and New Zealand, and Grahamichthys Whitley from New Zealand. Both had been previously classified in the family Eleotrididae. The Thalasseleotrididae is demonstrably monophyletic on the basis of a single synapomorphy: membrane connecting the hyoid arch to ceratobranchial 1 broad, extending most of the length of ceratobranchial 1 (= first gill slit restricted or closed). The family represents the sister group of a newly diagnosed Gobiidae on the basis of five synapomorphies: interhyal with cup-shaped lateral structure for articulation with preopercle; laterally directed posterior process on the posterior ceratohyal supporting the interhyal; pharyngobranchial 4 absent; dorsal postcleithrum absent; urohyal without ventral shelf. The Gobiidae is defined by three synapomorphies: five branchiostegal rays; expanded and mediallyplaced ventral process on ceratobranchial 5; dorsal hemitrich of pelvic-fin rays with complex proximal head. This study represents a contribution to our ongoing clarification of the family Eleotrididae, which has served historically as a repository for genera not classified among the more derived gobioids (= Gobiidae as defined here). Copyright © 2012 · Magnolia Press.


Kuzmina M.L.,University of Guelph | Johnson K.L.,Manitoba Museum | Barron H.R.,Environmental and Life science | Hebert P.D.N.,University of Guelph
BMC Ecology | Year: 2012

Background: Because arctic plant communities are highly vulnerable to climate change, shifts in their composition require rapid, accurate identifications, often for specimens that lack diagnostic floral characters. The present study examines the role that DNA barcoding can play in aiding floristic evaluations in the arctic by testing the effectiveness of the core plant barcode regions (rbcL, matK) and a supplemental ribosomal DNA (ITS2) marker for a well-studied flora near Churchill, Manitoba.Results: This investigation examined 900 specimens representing 312 of the 354 species of vascular plants known from Churchill. Sequencing success was high for rbcL: 95% for fresh specimens and 85% for herbarium samples (mean age 20 years). ITS2 worked equally well for the fresh and herbarium material (89% and 88%). However, sequencing success was lower for matK, despite two rounds of PCR amplification, which reflected less effective primer binding and sensitivity to the DNA degradation (76% of fresh, 45% of herbaria samples). A species was considered as taxonomically resolved if its members showed at least one diagnostic difference from any other taxon in the study and formed a monophyletic clade. The highest species resolution (69%) was obtained by combining information from all three genes. The joint sequence information for rbcL and matK distinguished 54% of 286 species, while rbcL and ITS2 distinguished 63% of 285 species. Discrimination of species within Salix, which constituted 8% of the flora, was particularly problematic. Despite incomplete resolution, the barcode results revealed 22 misidentified herbarium specimens, and enabled the identification of field specimens which were otherwise too immature to identify. Although seven cases of ITS2 paralogy were noted in the families Cyperaceae, Juncaceae and Juncaginaceae, this intergenic spacer played an important role in resolving congeneric plant species at Churchill.Conclusions: Our results provided fast and cost-effective solution to create a comprehensive, effective DNA barcode reference library for a local flora. © 2012 Kuzmina et al.; licensee BioMed Central Ltd.


Mooi R.D.,Manitoba Museum | Mooi R.D.,University of Manitoba | Randall J.E.,Bishop Museum
Zootaxa | Year: 2014

Pempheris bexillon new species is described from the 129 mm SL holotype and 11 paratypes (119-141 mm SL) from the Comoro Islands. Twelve other specimens have been examined from the Agaléga Islands, Mascarene Islands, and Bassas da India (Madagascar). It is differentiated from other Pempheris by the following combination of characters: a yellow dorsal fin with a black, distal margin along its full length, broadest on anterior rays (pupil-diameter width) and gradually narrowing posteriorly, the last ray with only a black tip; large, deciduous cycloid scales on the flank; dark, oblong spot on the pectoral-fin base; anal fin with a dark margin; segmented anal-fin rays 38-45 (usually >40); lateral-line scales 56-65; and total gill rakers on the first arch 31-35; iris reddish-brown. Tables of standard meristic and color data for type material of all nominal species of cycloid-scaled Pempheris in the Indo-Pacific are provided. Copyright © 2014 Magnolia Press.


Mooi R.D.,Manitoba Museum | Williams D.M.,Natural History Museum in London | Gill A.C.,University of Sydney
Zootaxa | Year: 2011

The assertion that phylogenetic inference algorithms are not authoritarian because results are repeatable, predictable and freely available misses the point that the authority resides in underlying algorithm models that are not cladistic. We show that optimization procedures can group using symplesiomorphy and that optimization is not always equivalent to cladistic argumentation. Because parsimony and Bayesian algorithms can obtain the same answer from the same data set is not evidence that they are Hennigian; examples exist where these methods do not provide the same result from the same data. Using 'reversals' as evidence in systematics is problematic because the question, "Reversal to what?" has no straightforward answer. This confusion can be eliminated by recognizing that homologues are the parts of organisms and homologies are the relationships between the parts, and that the latter is a hierarchical concept rather than transformational. We clarify that Hennig's auxiliary principle pertains to potential synapomorphy, meaning for molecular work that it is the presence of a particular derived nucleotide that is shared in a given position of aligned sequences of two or more taxa that should be considered homologous until proven otherwise, not simply the alignments themselves. We reiterate that not all data are evidence and we specifically reject homoplasy as a source of 'evidence' for systematics. We further reject the view that conflict among data should be resolved through methodology. It is the data that should be our primary focus, as it is our attempts to identify and clarify homologues worthy of suggesting relationships (homology) that are primary in systematics. Copyright © 2011 Magnolia press.


Gill A.C.,University of Sydney | Mooi R.D.,Manitoba Museum
Zootaxa | Year: 2011

In short, the charges leveled against us by Wiley et al. (2011) do not stand up to scrutiny. We had no ulterior motive in bringing what we consider to be legitimate concerns to the attention of our research community. We hope that the real issues-as detailed in our paper (Mooi & Gill 2010)-can now be discussed without further distraction. Copyright © 2011 Magnolia press.


Mooi R.D.,Manitoba Museum | Gill A.C.,Arizona State University
Zootaxa | Year: 2010

We contend that the move away from providing character evidence with phylogenies has diminished fish systematics and systematics in general, and amounts to a crisis. Present practices focus on solutions to matrices rather than on character homology, and rely on algorithms and statistics rather than biology to determine relationships. Optimization procedures in tree-building programs are phenetic and no longer employ homology, the original foundation of cladistics. Evidence for phylogenies is presented in a manner that obscures character conflict and makes meaningful debate difficult. The role of morphological characters has largely been reduced to their optimization and reinterpretation on the revealed "truth" of molecule-based topologies. All of this has resulted in a schism between molecular and morphological phylogeneticists. We examine several examples, focusing on Percomorpha and Gobioidei, to illustrate the shortcomings of recent approaches. We feel that phylogenetics can only move forward by recognizing that molecules are small-scale morphology; molecular data are not substantively different from larger-scale morphological data and should be treated in much the same manner. Careful investigation of homology and transparent presentation of evidence will keep our work and our science relevant. We suggest four measures that need reintroduction to phylogenetic practice in order to bring systematics back to its fundamental principles: (1) examine data quality, character distribution, and evidence; plot characters to identify and examine character conflict, and weigh evidence for homology, (2) explore the nature of character information-data become characters only after they are understood, (3) question assumptions of methods, common practice is not necessarily indicative of the ideal analysis, (4) in particular, question and investigate optimization as a method and what its impact is on character homology and the meaning of synapomorphies; use biology, not algorithms to make homology decisions. Copyright © 2010 Magnolia Press.


The composition of the Microdesminae has been inconsistently reported in recent molecular studies. A monophyletic Microdesminae consisting of both Indo-Pacific and New World/Atlantic genera is diagnosed here by the following synapomorphies: maxilla with elongate projection extending anteriorly over ascending processes of premaxilla; palatine medial process absent; single dorsal process on cleithrum; supracleithrum oriented vertically and closely applied to cleithrum; posttemporal with elongate posteroventral process; body slender and elongate, with associated increase in number of vertebrae and median fin rays (total vertebrae 42-66 with 19 or more precaudal vertebrae, total dorsal-fin rays 42-78, anal-fin rays 27-43), slender pelvis with anterior extensions of the pelvic intercleithral cartilage, and decrease in number of pelvic-fin rays (with a spine and 2-4 segmented rays); single dorsal fin; dorsal-fin spines usually 12 or more; predominantly 1:1 relationship between interneural spaces and anterior dorsal-fin pterygiophores; and first (supernumerary) ray on first anal pterygiophore a bilaterally paired, segmented ray. Several of these characters (particularly single dorsal process on cleithrum, posttemporal with elongate posteroventral process) support a possible relationship between microdesmines and Schindleria, as does dorsal gill-arch morphology. © 2010 Magnolia Press.


Robson S.P.,Manitoba Museum | Young G.A.,Manitoba Museum
Journal of Paleontology | Year: 2013

Six species of conulariids, assigned to four genera, were recovered from the type locality of the Cat Head Member of the Red River Formation in southern Manitoba, Canada. These are middle Katian (Late Ordovician) in age. The most abundant conulariid species from this locality, Conularia porcella, is new, and is represented by 21 specimens. Additionally, 28 three-dimensionally preserved micromorphic conulariids, assigned to Eoconularia aff. loculata, were recovered using acetic acid preparation from limestone samples of late Katian (Late Ordovician) age. These samples had been collected from Churchill, northern Manitoba, by the Geological Survey of Canada's J. B. Tyrrell in 1894. These taxa are unusually abundant for conulariids, which are normally represented by only a few specimens from any given locality, and this abundance may be a reflection of the exceptional preservation at these two localities. Copyright © 2013, The Paleontological Society.


Robson D.B.,Manitoba Museum
Canadian Field-Naturalist | Year: 2010

The bugseeds (Corispermum spp.) are a genus of annual plants that are uncommon due to their psammophilic, ruderal habit. Bugseeds are typically found in natural areas with some bare sand, like sand dunes, but are also present in anthropogenically impacted sandy or gravelly areas. Increasing dune stabilization may be causing the endangerment of some Bugseed species. Assessing the rarity of the five species in Canada is hindered by the lack of recently collected specimens and the use of out-dated nomenclature in herbaria. Specimens of bugseeds from major herbaria all across Canada were examined and re-identified using the most recent taxonomic treatment in the Flora of NorthAmerica. Hairy Bugseed (C. villosum) was the most commonly collected taxon and Hooker's Bugseed (C. hookeri var. pseudodeclinatum) the rarest. The natural distribution of all taxa, except Alaskan Bugseed (C. ochotense) which is only found in the far north, is from British Columbia to Ontario. Hairy, Hooker's and American Bugseed (C. americanum) are also found in Quebec, where they may have been introduced from further west. Summaries of Bugseed localities and habitats, and distribution maps are presented to facilitate the status assessment of plants in this genus.


Robson D.B.,Manitoba Museum
Canadian Field-Naturalist | Year: 2011

To provide a more accurate assessment of the rarity of the plant genus Corispermum (Amaranthaceae), commonly known as bugseeds, in Manitoba, I undertook a survey of all historical populations. In total, 68 quarter sections were selected for presence/absence surveys; 37 of them contained at least one species of bugseed. Only 10 of the 20 historical populations in Manitoba were relocated. The total estimated size of known bugseed populations in Manitoba in 2010-2011 was approximately 9 820 to 13 060 individuals. American Bugseed (C americanum (Nutt.) Nutt. var. americanum) is the most abundant and widespread of the bugseeds in Manitoba, followed by Hairy Bugseed (C. villosum Rydb.). There is only one population of Hooker's Bugseed (C. hookeri Mosyakin var. hookeri) in the province. Pallas' Bugseed (C. pallasii Steven) was not relocated and should probably be considered extirpated in Manitoba. The habitats at 61% of the localities where bugseeds were confirmed are anthropogenically disturbed, the most common habitat being roadsides with exposed bare sand. Of the localities where bugseeds were not relocated, 67% occurred in natural sandy areas, suggesting that dune stabilization is a major threat to the continuing persistence of these species.

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