Mitogenome sequence ofCirriformiacf.tentaculata(Terebellida, Cirratulidae), a species of marine polychaete worm, was determined in this study. This is the first mitogenome reported for genusCirriformiaand family Cirratulidae. This complete mitogenome is 15,495 bp in length, containing 13 protein coding genes (PCGs), two ribosomal RNAs (rRNAs), and 23 transfer RNAs (tRNAs). The mitogenome ofCirriformiacf.tentaculatahas high A + T content of 59.5% (A, 29.5%; C, 26.9%; G, 13.6%; T, 30.0%). In neighbour-joining (NJ) analysis,Cirriformiacf.tentaculatais clustered with the components of order Terebellida. [ABSTRACT FROM PUBLISHER]