No common name

Nygolaimus parvus

ORDER Dorylaimida

FAMILY

Nygolaimidae

TAXONOMY

Nygolaimus parvus Thorne, 1974.

OTHER COMMON NAMES

None known.

PHYSICAL CHARACTERISTICS

Classified as predatory and free-living, with a length of 0.051-0.055 in (1.3-1.4 mm). They are moderate-sized nematodes with relatively thin cuticles. The body is twisted so that when observed from an upper and lower viewpoint, only the head and tail can be seen. The neck takes up about two-thirds of the body length. The lip region is apparently set off by a modest constriction, with papillae low and rounded. The lateral field is one-fourth of the body width. The mural tooth is deltoid in shape, set in the left sub-ventral wall of the cheilostomal region, of length 0.000866 in (22 pm), a length that is somewhat less than the width of the lip region. The complete stoma is divided into three parts: a thin-walled cheilostomal vestibule, the cheilostome with the mural tooth, and an elongated thick-walled esophastome. The esophagus begins as a slender tube, and then slowly expands two-thirds of the way to the posterior, which then nearly fills the body cavity. A sheath encloses the posterior portion (postcorpus) of the esophagus. The three glands at the junction of the esophagus and stomach are well developed and discrete. At this site, the opening (cardia) is an elongated hemispheroid, which is one-fourth the body width and is usually obscured by the cardiac glands. The intestinal granules are colored a light brown, and sometimes form a slightly tessellated pattern. The rectum and pre-rectum both are about as long as the anal body diameter. Both sexes have similarly shaped tails, generally conoid and bluntly rounded.

DISTRIBUTION

Midwestern to western United States; especially in South Dakota, North Dakota, Minnesota, and Montana. (Specific distribution map not available.)

HABITAT

Live in native soils.

BEHAVIOR

Classified as predatory and free-living.

FEEDING ECOLOGY AND DIET

Predacious on other small, soil-inhabiting organisms.

REPRODUCTIVE BIOLOGY

The female vulva is transverse, and is smaller and of a different form than those of other species within the genus. The vagina extends about 40% of the body. The reflexed ovaries extend about two-thirds the distance back to the vulva. The eggs are 3-4 times as long as the body width. Males have lateral guiding pieces and poorly developed ventromedial supplements.

CONSERVATION STATUS

Not listed by the IUCN.

SIGNIFICANCE TO HUMANS None known. ♦

Essentials of Human Physiology

Essentials of Human Physiology

This ebook provides an introductory explanation of the workings of the human body, with an effort to draw connections between the body systems and explain their interdependencies. A framework for the book is homeostasis and how the body maintains balance within each system. This is intended as a first introduction to physiology for a college-level course.

Get My Free Ebook


Post a comment