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R.M. Wood

Publications and source records attributed to R.M. Wood.

3 recordsLinked to original sources

Etheostoma erythrozonum, a new species of darter (Teleostei: Percidae) from the Meramec River drainage, Missouri

A new species of darter, Etheostoma erythrozonum, is described from the Meramec River drainage of Missouri, USA. Etheostoma erythrozonum is the first known fish species endemic to the Meramec River drainage. It differs morphologically and genetically from populations of its sister species, Etheostoma tetrazonum, from the Gasconade River, Osage River, and Moreau River drainages.

Missouri↗

Crystallaria cincotta, a new species of darter (Teleostei: Percidae) from the Elk River of the Ohio River drainage, West Virginia

A new species of percid, Crystallaria cincotta, is described from the Cumberland, Elk, Green, and Muskingum river drainages of the Ohio River basin, USA. It differs from populations of Crystallaria asprella of the Gulf Coast, lower Mississippi River, middle Mississippi River, upper Mississippi River, and Wabash River drainages by having a reduced number of cheek scale rows restricted to the post-orbital region, a falcate margin on the pelvic fins, a preorbital blotch distinctly separate from the anterior orbital rim, and a wide mouth gape. The Elk River population is also divergent genetically from populations of the Gulf Coast, lower Mississippi River, and upper Mississippi River drainages. Crystallaria cincotta, discovered in the Elk River of the Ohio River drainage in 1980, is a rare species with the only extant population represented by 12 individuals collected from 1980-2005 from the lower 36 km section of the Elk River, West Virginia. Copyright ?? 2008 Magnolia Press.

Zootaxa↗

Phylogeographic analyses suggest multiple lineages of Crystallaria asprella (Percidae: Etheostominae)

The crystal darter, Crystallaria asprella , exists in geographically isolated populations that may be glacial relicts from its former, wide distribution in the Eastern U.S. An initial phylogeographic survey of C. asprella based upon the mitochondrial cytochrome b (cyt b ) gene indicated that there were at least four distinct populations within the species: Ohio River basin, Upper Mississippi River, Gulf coast, and lower Mississippi River. In particular, the most divergent population was the most recently discovered, from the Elk River, WV, in the Ohio River basin, and it was postulated that this population represents an undescribed, potentially threatened species. However, differentiation observed at a single gene region is generally not considered sufficient evidence to establish taxonomic status. In the present study, nucleotide variation at the mitochondrial control region and a nuclear S7 ribosomal gene intron were compared to provide independent verification of phylogeographic results between individuals collected from the same five disjunct populations previously surveyed. Variation between populations at the control region was substantial (except between Gulf drainages) and was concordant with patterns of sequence divergence from cyt b . Only the Elk River population was resolved as monophyletic based upon nuclear S7, but significant differences based upon Φ ST statistics were observed between most populations. Morphometric data were consistent with molecular data regarding the distinctiveness of the Elk River population. It is proposed that populations of C. asprella consist of at least four distinct population segments, and that the Elk River group likely constitutes a distinct species.

Alabama, Arkansas, Georgia, Louisiana, Mississippi↗