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Common name: Mermis nigrescens

Scientific name: Mermis nigrescens


Kingdom: Animalia

Phylum: Nematoda

Class: Adenophorea

Order: Mermithida

Family: Mermithidae

Genus: Mermis

Species: M. nigrescens

Commonly known as the round worm. Mermis Nigrescens is a worm the ranges from being microscopic to about 6 to 8 inches long, which is about 15 to 20 centimeters. Their coloration, brownish. Identifying their characteristics, Adenophoreans are considered non-segmented pseudocoelomates. Non-segmented pseudocoelomates are creatures possessing a 3 tissue layered body that has a fluid filled body cavity. Mermis Nigrescens have four layers ,endocuticle, epicuticle, exocuticle, and mesocuticle. The subcuticular is the cellular hypodermis layer that secretes the cuticle.

Mermis Nigrescens are found on the British Isles, North America, and Europe. While they are larvae M. nigrescens worms live in mainly grasshoppers and locusts and can infect other insects as well. Before they transform into adults they borrow out of a host, and the larvae dig into the soil. Mermis Nigrescens are not considered threatened or endangered. So they are not shrinking nor are the growing. There are about 96 families of Adenophorea.

In 1994 there were about 20,000 species of nematoda. And there are about 80,000 to 1,000,000 total species of nematoda living on the planet. Mermis nigrescens are herbivores, carnivores, predators, and omnivores! Their diet would include body fluid, blood, mucus, and intestinal contents. They use a form of stylet which is a hard, sharp spear and they use the stylet for feeding. They feed by using the stylet to puncture the cells. Then they can empty the cells for the contents inside. Finally, there are some more interesting facts about Mermis Nigrescens such as the females remain in the soil until they emerge when they are pregnant. When the females emerge they emerge in late spring and in the humid climate. When the climate is cool, the females remain in the ground because of it. They can die from constant direct sunlight.

Author: Ashlee C

Published: 02/2008

Sources: "Adenophorea." Answers.Com. 2008. 30 Jan. 2008 .

"Adenophorea." Novelguide.Com. 14 Feb. 2008 .

"Mermis Nigrescens." 29 Jan. 08. 31 Jan. 2008 .

"Roundworms: Adenophorea - No Common Name (Mermis Nigrescens): Species Accounts." 12 Feb. 2008.

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