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Winnipeg, Canada

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.

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.

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.

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.

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