A plasmid carrying a cDNA sequence coding for elongation factor EF‐1α from Artemia was used to probe blots of mRNA and chromosomal DNA from Artemia. A messenger length for EF‐1α corresponding to 1850 nucleotides was found. Southern blots pointed to a limited number (1–4) genes, coding for EF‐1α. From an Artemia gene library a recombinant phage was isolated, which contains genomic sequences of EF‐1α. S1‐nuclease mapping indicated the presence of intervening sequences within this cloned gene.