A quick script to get the order of a species if you know it's latin binomial name using the Reol library http://cran.r-project.org/web/packages/Reol/index.html

getOrderEOL.R

library(Reol)


getOrder <- function(binom_taxa, db = "NCBI Taxonomy"){
  MyEOLs <- DownloadSearchedTaxa(binom_taxa, to.file=FALSE)
  hier <- DownloadHierarchy(MyEOLs, FALSE, database=db)
  taxonomic_info <- CombineHierarchyInfo(hier)
  ord <- which(taxonomic_info[[2]]=="Order")
  return(taxonomic_info[[1]][ord,1])
}

ord1 <- getOrder("Laminaria saccharina")
ord2 <- getOrder("Saccharina latissima")


ord1
ord2