Morphometry and biomass determination of dominant mayfly larvae (Ephemeroptera) in running waters

Length-mass regressions and length-carbon mass regressions have been developed to estimate biomass from measured length parameters for four different taxa of mayfly larvae; special attention has been focused on practical applicability. Body length, head-capsule width, mesonotum and pronotum width are the most suitable length parameters among seventeen body dimensions considered here; as a rule, a power function y=ax b is qualitatively better than a linear, exponential or square power function. The choice of a regression model depends on the respective body dimension and the measuring range. These length-biomass regressions obtain considerable significance for practical applicability in production biology