Rhabditis terricola: An opportunistic nematode parasite of earthworm cocoons

During a study on the breeding rate of the earthworms Lumbricus rubellus and Eisenia foetida, nematodes identified as Rhabditis terricola were found consistently in large numbers in earthworm cocoons that failed to hatch after an adequate incubation period. This nematode species, which was previously known as a saprophyte, was found to invade earthworm cocoons and reproduce within, causing extensive productivity losses in earthworm cultures. In this study, R. terricola was effectively eradicated from earthworm cultures by rinsing the earthworms in tap water and transferring them repeatedly to sterile bedding.