Ec. Phillips et Rv. Kilambi, USE OF COARSE WOODY DEBRIS BY DIPTERA IN OZARK STREAMS, ARKANSAS, Journal of the North American Benthological Society, 13(2), 1994, pp. 151-159
Aquatic dipterans were sampled from coarse woody debris (CWD) and ston
y benthic habitats from February 1991 through February 1992 in the Whi
te River, Illinois River, and Clear Creek of the Ozark Plateau in Arka
nsas. Chironomidae was the numerically dominant taxonomic group, and t
hey were collected in significantly greater densities from CWD than fr
om benthic habitats; but densities of other dipterans did not differ s
ignificantly between habitat types. Representatives of five taxa were
collected in significantly greater densities from benthic habitats, an
d seven from CWD. The greatest estimated mean density of dipterans occ
urred during the spring, but differences were not significant because
of high variation within seasons. The degree of decay of CWD was an im
portant microhabitat factor for representatives of six taxa, of which
four were xylophagous chironomids. The xylophages that were affected b
y degree of decay were Brillia flavifrons, Polypedilum fallax, Stenoch
ironomus sp., and Xylotopus par. Eukiefferiella spp. and Phaenospectra
sp. were the non-xylophages affected by decay stage. Biofilm volume a
ppeared to be a less important factor in CWD use, but was important fo
r representatives of two taxa (B. flavifrons and Eukiefferiella spp.).