New genome size estimates in arthropods

We report size estimates for a variety of species within Arthropoda that were heretofore unrepresented in any genome size database. Arthropod genome size measurements provide data for all molecular studies, including future sequencing projects, and for comparative analyses of genome size evolution within and between clades. Samples for these studies were obtained from field collections in central Texas, and from species kindly provided for these studies from laboratory cultures. Samples were dissected for brain tissue that was co-prepared in Galbraith buffer along with a suitable standard (Drospohila melanogaster, D. virilis, or chicken (Gallus gallus domesticus) red blood cells). Nuclei from the sample and standard were isolated by 15 strokes with the B pestle in a 2 ml Dounce tissue grinder then stained with Propidium Iodide. After a minimum of 20 minutes stain time in the cold and dark, the relative fluorescence of sample and standard were measured by flow cytometry. DNA quantity is estimated as the ratio of sample mean fluorescence to standard mean fluorescence times the amount of DNA in the standard. Repeat measurements produce standard errors of 1-3% for most estimated genomes. Data is presented for a number of new species, new genera and several new families whose genomes were unknown to this time.