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D. R. Lenat

Publications and source records attributed to D. R. Lenat.

6 recordsLinked to original sources
USGS2011

A new species of Perlesta (Plecoptera: Perlidae) from North Carolina with additional records for North Carolina and Virginia

Twenty-eight species of Nearctic Perlesta are currently recognized (Stark 1989, 2004; Kondratieff et al. 2006, 2008; Grubbs and DeWalt 2008, Grubbs and DeWalt 2011, Kondratieff and Myers 2011). Interestingly, but needing confirmation, Perlesta has been recently recorded from Central America (Gutiérrez-Fonseca and Springer 2011). Continued collecting and study of Perlesta from North Carolina by the authors revealed one additional undescribed species. Ten species of Perlesta currently have been recorded from North Carolina (Stark 1989, 2004, Kondratieff et al. 2006, 2008, Grubbs and DeWalt 2008). Additionally, new Perlesta species records are given for Virginia. The terminology used in the description of the male adult follows Stark (1989, 2004).

North Carolina↗
USGS2007

Two new genera of Lumbriculidae (Annelida, Clitellata) from North Carolina, USA

Recent benthic macroinvertebrate collections from North Carolina contained many undescribed oligochaete taxa, mostly belonging to the family Lumbriculidae. Three of the new species had arrangements of spermathecae and atria previously unreported for the family, and were assigned to new two genera. Pilaridrilus is distinguished by the location of spermathecal pores five segments behind the male pores. The single species, Pilaridrilus uliginosus , also has unusually complex penes and spermathecae. Martinidrilus is distinguished by spermathecae beginning more than two segments anterior to the atrial segment, and also by the the vasa deferentia, which join a common duct before joining the atria. The two Martinidrilus species also have unusual digitiform blood vessels in posterior segments. Martinidrilus carolinensis has lateral spermathecae in VI, and Martinidrilus arenosus has dorsolateral spermathecae in VII and VIII. Because arrangement and morphology of reproductive organs do not resemble those of described lumbriculids, the phylogenetic affinities of the new species are not clear. These new genera and species were generally collected from areas of high water quality, suggesting that lumbriculids can be useful in water quality monitoring and conservation evaluation.

North Carolina↗
USGS1989

Effects of land use on the water quality and biota of three streams in the Piedmont province of North Carolina

Three small streams in North Carolina 's northern Piedmont were studied to compare the effects of land use in their watersheds on water quality characteristics and aquatic biota. Devil 's Cradle Creek (agricultural watershed) had more than two times the sediment yield of Smith Creek (forested watershed) (0.34 tons/acre compared to 0.13 tons/acre), and Marsh Creek (urban watershed) had more than four times the yield of Smith Creek (0.59 tons/acre). Concentrations of nutrients were consistently highest in Devil 's Craddle Creek. Concentrations of total copper, iron, and lead in samples from each of the three streams at times exceeded State water quality standards as did concentrations of total zinc in samples from both Smith and Marsh Creeks. Successively lower aquatic invertebrate taxa richness was found in the forested, the agricultural, and the urban watershed streams. Invertebrate biota in Smith Creek was dominated by insects, such as Ephemeroptera, that are intolerant to stress from pollution, whereas Devil 's Cradle Creek was dominated by the more tolerant Diptera, and Marsh Creek was dominated by the most pollution-tolerant group, the Oligochaeta. Fish communities in the forested and agricultural watershed streams were characterized by more species and more individuals of each species, relative to a limited community in urban Marsh Creek. Three independent variables closely linked to land use--suspended-sediment yield, suspended-sediment load, and total lead concentrations in stream water--are inversely associated with the biological communities of the streams.

North Carolina↗