Tripylina arenicola

Zhao, Zeng Qi, 2009, A review of the genus Tripylina Brzeski, 1963 (Nematoda: Triplonchida), with descriptions of five new species from New Zealand, Zootaxa 2238, pp. 1-24 : 18-19

T. arenicola (de Man, 1880) Brzeski, 1963 (Type species)

Synonyms. Tripyla arenicola de Man, 1880

Tripyla (Trischistoma) arenicola de Man, 1880 (Schneider, 1939) Trischistoma arenicola (de Man, 1880) Schuurmans Stekhoven, 1951 Tripyla minor Cobb, 1893

Measurements (after Brzeski & Winiszewska-Ślipińska 1993). Females (n = 20): L = 810–1250 µm; a = 20–30; b = 4.7–6.8; c = 13.1–18.3; c’ = 1.9–3.2; V = 62–69%

Male: Brzeski & Winiszewska-Ślipińska (1993) stated that the only specimen was lost.

Description (after Brzeski & Winiszewska-Ślipińska 1993). Body ventrally arcuate when fixed, cuticle about 1 μm thick, not annulated. Head rounded, 18–22 μm diameter. Six long cephalic setae 10–14 μm long, or 52–74% of head diameter; four short cephalic setae 5–6 μm long. Stoma walls not thickened; dorsal tooth small, triangular; two subventral denticles posterior to dorsal tooth. A single ventromedian seta, thin,60–78 μm, or 30–42% of pharyngeal length from anterior end of body. Vulva pore-shaped; sclerotized pieces small, comma-shaped with tips directed towards vulva. Male with six papillate ventromedian supplements. Other details of male missing, because the only specimen was lost.

Diagnosis and Relationships. The main distinguishing feature of T. arenicola is the subventral denticles posterior to the dorsal tooth.

Females of T. arenicola are similar to those of T. macroseta , T. manurewa sp. nov., T. tearoha sp. nov., T. tamaki sp. nov., T. sheri , and T. ursulae in body length, and shorter than all other species ( T. longa , T. stramenti , T. yeatesi sp. nov. and T. kaikoura sp. nov.) ( Table 3).

T. arenicola is similar to T. ursulae in having two subventral denticles posterior to the dorsal tooth and differs from T. tearoha sp. nov., T. manurewa sp. nov., T. tamaki sp. nov., T. sheri , and T. macroseta , which have the denticles anterior to the dorsal tooth ( Table 3).

T. arenicola can be differentiated from T. ursulae by the absence of setae in the cervical region.

Habitat and distribution. Terrestrial. Type locality Katwijk, Holland. Recorded from more than 20 countries, including eight in Europe ( Netherlands, Switzerland, Poland, Austria, Hungary, Italy, Lithuania, Russia), seven in Asia ( Georgia, Uzbekistan, India, Vietnam, Indonesia, Korea,), three from North and Central America ( Canada, Mexico, Costa Rica), one from South America ( Paraguay) and one from South Pacific Ocean ( Fiji Islands).

Etymology. The species epithet is derived from the Latin words arena = sand, and incola = an inhabitant.

Tripylina longa Brzeski & Winiszewska- Ś lipi ń ska, 1993

Measurements (after Winiszewska-Ślipińska 1993). Females (n = 8): L = 1480–1720 μm; a = 33–40; b = 6.3–7.4; c = 24.9–30.3; c’ = 1.7–2.6; V = 76–80%; anterior cervical seta = 50–74 μm from anterior end; posterior cervical seta = 49–63 μm from anterior end.

Male (n = 1): L = 1640 μm; a = 19; b = 6.8; c = 26.6; c’ = 1.8; ventromedian papillae = 5; spicule along arc = 52 μm; gubernaculum = 19 μm; anterior cervical seta = 88 μm from anterior end; posterior cervical seta = 175 μm from anterior end.

Description (after Brzeski & Winiszewska-Ślipińska 1993). Anterior part of relaxed specimens straight, posterior spiral. Cuticle composed of two distinct layers, 1–1.5 μm thick. Head 25–28 μm wide. Six long cephalic setae 15–18.5 μm long, or 59–71% of head diameter; four short cephalic setae 5–7 μm long. Dorsal part of stoma walls thickened; dorsal tooth relatively large, directed posteriad; two subventral denticles anterior to dorsal tooth,. Two ventromedian setae in cervical region, anterior 23–34% of pharyngeal length from anterior end, posterior 57–68%. Vulva pore-shaped, sclerotized pieces large. A pair of subdorsal setae on anterior part of tail. Some females with another pair of subdorsal setae near junction of intestine and rectum.

Male similar to female. Five papillate ventromedian supplements near cloaca. Spicules narrow, sicle shaped. Gubernaculum U-shaped in cross section, surrounding spicules dorsally and laterally.

Diagnosis and Relationships. The main distinctive feature of T. longa is the large dorsal tooth directed posteriad. It is the longest recorded in the genus.

Females of T. longa are similar to those of T. stramenti , T. kaikoura sp. nov. and T. yeatesi sp. nov. in body length, and longer than all other species ( T. tearoha sp. nov., T. manurewa sp. nov., T. tamaki sp. nov., T. sheri , T. arenicola , T. ursulae and T. macroseta ) ( Table 3).

T. longa is also similar to T. kaikoura sp. nov., T. stramenti and T. yeatesi sp. nov. in having two subventral denticles anterior to dorsal tooth, but its two cervical setae differ from T. stramenti which has one cervical seta, and from T. kaikoura sp. nov. and T. yeatesi sp. nov. which lack cervical setae ( Table 3).

T. longa is similar to T. tearoha sp. nov., T. manurewa sp. nov. and T. tamaki sp. nov. in having two subdorsal setae on tail, but its two cervical setae differ from T. tearoha sp. nov., T. manurewa sp. nov. and T. tamaki sp. nov. which have a single ventromedian seta and two pairs of lateral setae in the cervical region, respectively.

Habitat and distribution. Found in clay soil around roots of grasses on the bank of Ema River, Italy.

Etymology. Not stated.