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Gnathostomulids: Gnathostomulida

Physical Characteristics, Red Haplognathia (haplognathia Ruberrima): Species AccountGEOGRAPHIC RANGE, HABITAT, DIET, BEHAVIOR AND REPRODUCTION, GNATHOSTOMULIDS AND PEOPLE, CONSERVATION STATUS

RED HAPLOGNATHIA (Haplognathia ruberrima): SPECIES ACCOUNT

Gnathostomulids live all over the world but mainly in the northern part of the Atlantic Ocean and the southern part of the Pacific Ocean.


Gnathostomulids live on sheltered beaches, near sea grasses and mangroves, and between coral reefs.

Gnathostomulids graze on bacteria and threads of fungus attached to sand grains.


Gnathostomulids glide between sand grains. They contract when disturbed. Some species spin a cocoon of mucus. Gnathostomulids make both eggs and sperm. Sperm is transferred by mating and is stored either between the digestive tract and outer tissue layer or in a storage pouch. Only one large egg matures at a time. The egg joins with sperm and then is laid by bursting through the worm's back. The eggs hatch directly into young animals, which grow to adults.


Gnathostomulids have no known importance to people.


Gnathostomulids are not considered threatened or endangered.

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