it is approx. 18 months :)
The life span of a round worm varies according to the particular type of roundworm. Some roundworms can survive in the intestines of their host for 7 years or more.
Phylum Nemertea.
The ribbon worm is an example of a species in the phylum Nemertea. These worms are known for their long, ribbon-like bodies and are found in marine environments worldwide.
Ribbon Worm.
... It dies
1 inch to 85 feet
The Lineus Longissimus also known as the Ribbon Worm
ribbon worm
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I don't know about the Dawn ... but the longest worm measured 55m, a Ribbon worm cast up in Scotland. This is about 20m longer than the Blue Whale.
A Worm's Life was created in 1996.
life expectancy of a compost worm