Completar frases Zoology Fill in the Blank Nematode vs Annelid GameVersión en línea Fill in the blank in a Nematode and Annelid comparison. por Nathan Westfall 1 Nematodes lack the muscles that annelids have , but they both have muscles . They both have a located at their anterior and an anus located at their side . One major difference in their bodies is the fact that annelids are . Each is separated by walls called . Another key difference is the fact that nematodes have a pseudo - coelom , and annelids have a true . Most nematodes are , living off a host , but most are free - living .