Labronema ferox
Thorne, 1939
Photo Gallery-Konza Prairie
Photo Gallery-Homestead Nat'l Mon.

Measurements (from Thorne, 1939)
L = 3.0-3.6 mm; a = 35; b = 4.1; c = 100; V = 50
L = 3.0-3.5 mm; a = 43; b = 4.0-5.2; c = 100; T = 62

Description (from Thorne, 1939)
    Cuticle marked by radial striae which are especially prominent on the tail.  Lip region discoid, set off by deep constriction, more than three times as wide as high, and half as wide as base of neck.  Six thick lip flaps arched over vestibule.  Amphids roughly triangular with apertures about one-third head width.  Sensilla elements four, arranged fan-like.  Lateral cords about one-fourth the body width with coarse granules so densely packed as to obscure all traces of cells.  Lateral pores arranged in two lines.  Pharynx about one-third head width.  Encircling the lower portion of pharynx is a flexible muscular element which generally stands out distinctly from the wall proper.  Guiding ring double.  Spear about as long as, and one-sixth as wide as lip region, the aperture occupying almost one-half its length.  Anterior portion of esophagus one-fourth to one-third as wide as neck, narrowing slightly at nerve ring.  Posterior three-fifths of esophagus enlarged by gradual expansion until about half neck width.  In some specimens there is little difference in width of the two portions of the esophagus at their junction.  Five esophageal glands easily visible with perhaps an obscure sixth one opposite the dorsal gland.  Cardia unusually elongated, from one to one and one-half times as long as the body width.  Walls of intestine two or three times as thick as adjacent body cuticle, its cells obscure and packed with rather colorless granules.  Female prerectum length two or three times body width; rectum length about twice anal body diameter.  Vagina heavily cuticularized, extending half way across body.  Ovaries reflexed about half way to vulva.  Female tail hemispherical.  Posterior portion of male arcuate.  Supplements 20-27, the series beginning slightly anterior to the spicula.  Submedian papillae 6-8 pairs.  Caudal papillae 6-8 pairs.  Spicula dorylaimoid, distal ends slightly bent forward.  Lateral guiding pieces acute, slender, V-shaped.  Male prerectum variable in length but generally just within range of anterior supplements; in one male from Virginia the prerectum reached midway of the 20 supplements.
    Diagnosis: Labronema with the above measurements and general description.  Distinguished from its most closely related species, L. varicaudatum, and others by the broadly discoid lip region.
    A predacious species.  Intestines contained setae of oligochaetes.  One specimen contained what apparently was green algae or moss which may have been swallowed while catching living prey.
    Habitat: Soil about roots of cotton seedlings, Florence, S. C.; pine tree nursery, Kirbyville, Texas; daffodil bulbs, Texas (locality unknown); native plants, stream bank, Broad Run, Virginia.  All points in U. S. A.

DNA Sequences Obtained
Specimen: Collected:
SH-01  Homestead National Monument, Beatrice NE
9mi 4-30 LP2-10 9 Mile Prairie, First Survey