Rev: 12/21/2021
Tripylella Brzeski & Winiszewska-Slipinska, 1993
Synonyms:
Type species Tripylella intermedia. Synonymized from Paratripyla intermedia
The genera Tripylella Brzeski & Winiszewska-Ślipińska, 1993 and Tripyla Bastian, 1865 (Tripylinae, Tripylidae, Enoplida, Nematoda) are both diovarial and amphidelphic but are distinguished morphologically in the configuration of whorls of anterior sensillae. Both genera have six circumoral inner labial papillae, but in Tripyla the whorl of four cephalic setae is well-separated and posterior to the whorl of six outer labial setae while in Tripylella, the two whorls are very close together so that they appear as a single whorl of six, usually longer, and four, usually shorter, setae.
The genus Tripylina Brzeski, 1963 of the Trischistomatidae also has the outer labial and cephalic setae in a single whorl but the females are monovarial, prodelphic (Andrassy, 2007; Cid del Prado et al., 2010; and Cid del Prado et al., 2016).
Tripylella has a dorsal tooth and two subventral denticles.
The whorls of outer labial and cephalic setae are very close together so that they appear as a single whorl of six, usually longer, outer labial setae and four, usually shorter, cephalic setae.
In different species of the genus, the subventral teeth are either anterior or posterior to the dorsal tooth and usually are in a separate stomal chamber from the dorsal tooth.
The pharynx is uniformly cylindrical throughout its length with slight enlargement in the latter portion associated with the location of the pharyngeal glands.
About midway down its length the pharynx is surrounded by the nerve ring.
The cardia at the base of the pharynx is enlarged and comprised of six cells.
Female reproductive systems didelphic, amphidelphic.
The tail either tapers uniformly or is cylindrical in the anterior region and then narrows abruptly.
The spinneret at the tail terminus emits secretions of three caudal glands which provides adherence to substrates.
In species of Tripylella described thus far, males are extremely rare. When present, they have a row of ventral supplements extending anteriorly from the cloaca (Andrassy, 2007; Brzeski & Winiszewska-Ślipińska, 1993).
Species of the genus Tripylella are reported from moist soil, mosses and aquatic habitats.
Females:
Diovarial, amphidelphic.
Caudal glands open through spinneret at tail tip.
Nematodes of the family Tripylidae are generalist predators of small aquatic and soil organisms. Many authors have commented on the freshwater and wet 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).
Regulation of opportunistic species through predation.
Andrassy, I. 2007. Free-living nematodes of Hungary (Nematoda, Errantia), II. Hungarian Natural History Museum, Budapest, Hungary. 496 pp.
Brzeski, M.W. 1963. Nematode genera of the family Tripylidae (Nematoda, Enoplida). Acta Zoologica Cracoviensia, 8: 295-308.
Brzeski, M.W. 1964. Revision der Gattungen Tripyla Bastian und Paratripyla gen. n. (Nematoda, Tripylidae). Annales Zoologici, 22: 157-178.
Brzeski, M.W. 1965. On the identity of Trischistoma Cobb and Tripylina Brzeski. Nematologica, 11: 449.
Brzeski, M.W. & Winiszewska-Slipinska, G. 1993. Taxonomy of Tripylidae (Nematoda, Enoplia). Nematologica, 39: 12-52.
Butschli, O. 1873. Beiträge zur Kenntnis der freilebenden Nematoden. Nova Acta Academiae Caesareae Leopoldino-Carolinae Germanicae Naturae Curiosorum, 36: 1-144.
Cid del Prado, I., H. Ferris and S.A. Nadler. 2010. Soil inhabiting nematodes of the genera Trischistoma, Tripylina and Tripyla from M�xico and the USA with descriptions of new species. Journal of Nematode Morphology and Systematics 13-28-49.
Cid del Prado Vera, I., Ferris, H., Nadler, S.A., Lamothe Argumedo, R. 2012. Four new species of Tripylina Brzeski, 1963 (Enoplida: Tripylidae) from M�xico, with an emended diagnosis of the genus. Journal of Nematode Morphology and Systematics 15: 71-86.
Cid del Prado-Vera, I., Ferris, H., Nadler, S.A. 2016. Five new species of the genus Tripylella (Nematoda: Enoplida: Tripylidae). Zootaxa 4109(2):198-217
Cid del Prado-Vera, I., Ferris, H., Nadler, S.A. 2016. Five new species of the family Trischistomatidae (Nematoda: Enoplida) from North and Central America, with keys to the species of Trischistoma and Tripylina. Zootaxa 4109(2):173-197.
Yeates, G.W., T. Bongers, R. G. M. De Goede, D. W. Freckman, and S. S. Georgieva. 1993. Feeding habits in soil nematode families and genera—An outline for soil ecologists. Journal of Nematology 25:315-331