Rev 04/24/2023
Tripyla napaensis Cid del Prado, Ferris and Nadler, 2010
Note: A recent classification removes the suborder Tripylina from the order Enoplida and places it, along with suborders Tobrilina and Diphtherophorina, in the order Triplonchida (De Ley et al., 2006; De Ley & Blaxter, 2004). That move has not been generally adopted.
drawings and photomicrographs by Ignacio Cid del Prado
Female:
Body J-shaped after fixation and strongly curved or in a slight ventral spiral posteriorly.
Cuticle finely striated with striae more conspicuous at the anus level.
Head symmetrical, continuous with body contour.
Amphid apertures 10.2-16.3 um from the anterior end.
Inner labial sensillae papilliform; outer labial setae 7.1-9.2 um long or 29.5-42.9%of head width; cephalic setae conical and 3.1-5.1 um long, 4.1-5.1 um posterior to the outer labial setae.
Dorsal tooth small, wedge-shaped, stomal chamber narrow when not distended. Two very small subventral denticles 4.1-5.1 um anterior to the dorsal tooth.
Prominent cardia between esophagus and intestine,16.9-22.6 um long by 22.1-26.5 um wide.
Vulva with slightly protruding lips without sclerotised structures.
Anterior and posterior to the vagina are two oval-shaped glands filled with refractive material.
Spermatheca oval, 20.9-33.9 um long by 14.7-24 um wide, containing oval-shaped sperm.
Tail curved ventrally, tapering in anterior region and becoming narrowly cylindrical in posterior third, ending in a long spinneret.
Male:
Shape after fixation a simple spiral.
Head symmetrical and continuous with body contour.
Cuticle finely striated over whole length of body with slightly coarser striations in region of cloaca and tail.
Dorsal tooth small, wedge-shaped; very small subventral denticles 3.2-4.8 um anterior to dorsal tooth.
Fourteen ventral papillae observed at varying distances apart, the first 70 um from the anterior end and the last 50 um anterior to the cloacal opening.
Tail curved ventrally with fine but distinct striation, narrowing to cylindrical in the posterior 30% of its length, and ending in a long spinneret.
Spicules with bifid end, surrounded by a muscular pouch, manubrium 6.8-8.5 um wide; gubernaculum slightly curved.
Cid del Prado et al., 2010.
Reported median body size for this species (Length mm; width micrometers; weight micrograms) - Click:
Type locality and habitat: Western hills of the Napa Valley, 0.75 km west of UC Oakville Experimental Vineyard, Oakville, California (N 38, 25.99’; W 122,25.31’).
Collected from soil moisture seepage near California Black Oak (Quercus kelloggii).
Nematodes of the family Tripylidae are generalist predators of small aquatic and soil organisms. Many authors have commented on the freshwater andwet soil in which these nematodes are found, and on the nature of their prey based on observation of intestinal contents or from behavior. Among the recorded prey, as reviewed and collated by Small (1987), are nematodes, rotifers and protozoa (Cid del Prado et al., 2012).
Nematodes in the Tripylidae attach to soil particles or other substrate via adhesive material extruded from the caudal glands through the spinneret. Thus anchored, the body moves quite reapidly in water films, sometimes thrashing vigorously. This behavior has at least three possible purposes: 1. to make tactile contact with prey organisms, 2. to create currents that stir up the sediment and potential prey organisms settled therein, and 3. to anchor the nematode in currents of moving water.
Interestingly similar attachment and feeding behavior occurs in other nematode groups that, based on most characters, appear to be only distantly related. For example, the generalist predators of the Tripylidae are in the Class Enoplea, Subclass Enoplia, Order Enoplida, the specialist predators of other nematodes in the Mononchidae are in the Class Enoplea, Subclass Dorylaimia, Order Mononshida, while the bacterivorous Plectidae are in the Class Chromadorea, Subclass Chromadoria, Order Plectida, according to the phylogeny proposed by De Ley and Blaxter, (2002, 2004).
Ecophysiological Parameters:
Cid del Prado, I., H. Ferris and S.A. Nadler. 2010. Soil inhabiting nematodes of the genera Trischistoma, Tripylina and Tripyla from México and the USA with descriptions of new species. Journal of Nematode Morphology and Systematics 13-28-49.
De Ley, P., Decraemer, W. & Eyualem-Abebe. (2006). Introduction: summary of present knowledge and research addressing the ecology and taxonomy of freshwater nematodes. In Eyualem-Abebe, Andrassy, I. & Traunspurger, W. (Eds). Freshwater Nematodes: Ecology and Taxonomy. Wallingford, UK, CABI Publishing, pp. 3-30.
Zullini, A. (2006). Order Triplonchida. In Eyualem-Abebe, Andrassy, I. & Traunspurger, W. (Eds). Freshwater Nematodes: Ecology and Taxonomy. Wallingford, UK, CABI Publishing, pp. 293-323