Genus Tripylina Brzeski, 1963

Abunema Khera, 1971 .

Diagnosis (from Brzeski 1963, Zhao 2009 and Cid del Prado-Vera et al. 2012)

Trischistomatidae . Body length 0.8–1.8 mm. Cuticle smooth with numerous minute pores, thin, not annulated. Six longer outer labial setae and four shorter cephalic setae in a single circle. Buccal cavity with dorsal tooth in a stomatal chamber and two subventral denticles anterior or posterior to the latter. Pharyngeal-intestinal valve composed of three glands around anterior portion of intestine. Female reproductive system monodelphic with anterior reflexed ovary, post-vulval uterine sac present or absent; vagina with or without internal cuticularised pieces; vulva at 59–83% of body length from anterior extremity. Males rare; reproductive system monorchic, sperm cells ovoid or drop-shaped. Spicules narrow, sickle-shaped; when present, muscular pouch partially or completely encloses spicules. Papillose precloacal supplements present. Tail short, anteriorly conical and posteriorly cylindrical, strongly bent. Twenty-two species.

Type species

Tripylina arenicola (de Man, 1880) Brzeski, 1963 .

= Tripyla arenicola de Man, 1880 .

= Tripyla (Trischistoma) arenicola – Schneider, 1939.

= Trischistoma arenicola – Schuurmans Stekhoven, 1951.

Other valid species

T. bravoae Cid del Prado-Vera, Ferris, Nadler & Lamothe-Argumedo, 2012.

T. gorganensis Asghari, Pourjam, Heydari, Zhao & Ramaji, 2012 .

T. iandrassyi Cid del Prado Vera, Ferris & Nadler, 2016.

T. ixayocensis Cid del Prado-Vera, Ferris, Nadler & Lamothe-Argumedo, 2012.

T. kaikoura Zhao, 2009 .

T. longa Brzeski & Winiszewska-Ślipińska, 1993 .

T. macroseta (Vinciguerra & La Fauci, 1978) Tsalolikhin, 1983 .

= Trischistoma macroseta Vinciguerra & La Fauci, 1978 .

T. manurewa Zhao, 2009 .

T. montecilloensis Cid del Prado-Vera, Ferris, Nadler & Lamothe-Argumedo, 2012.

T. puxianensis Xu, Zhao, Wang & Zheng, 2013 .

T. rorkabanarum Cid del Prado Vera, Ferris & Nadler, 2016.

T. sheri Brzeski, 1963 .

= Tripyla (Trischistoma) sheri – Khera, 1970.

= Trischistoma ursulae Argo & Heyns, 1973 .

= Tripylina ursulae – Tsalolikhin, 1983.

T. stramenti (Yeates, 1972) Tsalolikhin, 1983 .

= Trischistoma stramenti Yeates, 1972 .

T. tamaki Zhao, 2009 .

T. tearoha Zhao, 2009 .

T. tlamincasensis Cid del Prado-Vera, Ferris, Nadler & Lamothe-Argumedo, 2012.

T. ursulae (Argo & Heyns, 1973) Tsalolikhin, 1983 .

= Trischistoma ursulae Argo & Heyns, 1973 .

T. valiathani Tahseen & Nusrat, 2010 .

T. yeatesi Zhao, 2009 .

T. ymyensis Tahseen & Nusrat, 2010 .

T. zhejiangensis Pham, Wang, Zhao & Zheng, 2013 .

Remarks

Tripylina was revised Andrássy (1985) who synonymised Abunema with Tripylina, and more recently by Zhao (2009) and Cid del Prado-Vera et. al. (2012). Cid del Prado-Vera et al. (2016) provided an updated key to the species of the genus. The muscular pouch found in some Tripylina species such as T. bravoae and T. longa almost completely surrounds the spicules, unlike the muscular pouch found in Tripyla (Triplonchida), which surrounds the proximal half of the spicules only. In Tripylina iandrassyi, there appears to be no muscle pouch. Males are known only for T. arenicola, T. bravoae, T. iandrassyi and T. longa .