Oscheius tipulae Lam & Webster (1971) Sudhaus, 1993

Falahzadah, Mohammad Hussain, Shokoohi, Ebrahim, Moravej, Gholam Hossein, Mashela, Phatu William, Madadi, Abdul Khalid & Karimi, Javad, 2021, Entomophilic nematodes, Diploscapter coronatus and Oscheius tipulae from Afghanistan, Zootaxa 4926 (3), pp. 401-416 : 407-409

Oscheius tipulae Lam & Webster (1971) Sudhaus, 1993

( Figs. 4 , 5 )

Measurements: Table 1.

Female: After the fixation, body length was slightly curved to ventral. Lateral field was not visible. Cuticle annulated; annuli 2.2 µm. Lip region was consistent with contour of the body, with six round lips and small papillae. Rhabditid Stoma was 15–19 µm long, with distinct cheilo- gymno- and stegostom. Cheilostom was exquisitely cuticularized. Cheilostom was shorter than gymnostom, and gymnostom had a well-cuticularized lumen. Stegostom had isomorphic glottoid apparatus with two to three denticles, and pharyngeal collar covered half of the stoma. Pharyngeal corpus was 1.7 to 1.9 times longer than length of isthmus, with metacorpus shorter than procorpus. Metacorpus was distinct and slightly swollen. Intestinal tissue surrounded Cardia conoid. Length of nerve ring at isthmus level made 59 to 75% of neck. Excretory pore opening at isthmus level extended at 65 to 87% of neck length. Deirid was not visible. Distinct difference was not observed in the intestine. The reproductive system was Didelphic-amphidelphic. Slightly projected Vulva was located at the middle part to the posterior of the body, and the oviduct was short. Uterus was tubular with a swollen lumen almost twice as long as the corresponding body diameter. The vagina with tiny walls extended to about a third of the width of the body. Rectum was 0.7 to 1.2 times longer than anal body diameter, and tail cornical had a sharp end. Phasmid covered 21 to 30% of the tail length from the anus.

Male: not found.

Remarks: the nematode examined is similar to the original description of O. tipulae provided by Lam and Webster (1971). However, the specimens had longer bodies (630–820 vs. 624–780 µm). It was different with Iranian population recorded by Karimi et al. (2018) in b value (5–6 vs. 5.2–11.1), c’ value (3.9–6.5 vs. 4.5–5.4), stoma (15– 19 vs. 13–14 µm), pharynx length (125–145 vs. 104–125 µm), and excretory pore from the anterior end (117–130 vs. 87–118 µm). In comparison with the nematodes examined by Sudhaus (1993), the Afghan specimen differed with having shorter pharynx (125–145 vs. 129–151 µm), body length (630–820 vs. 505–708 µm), b value (5–6 vs. 3.9–4.9) and tail length (60–105 vs. 70–95 µm). There are no significant differences for the other characters among the Afghan specimen and those studied by Sudhaus (1993). The differences among isolates are due to geographical distribution and habitat. Besides, the overla morphology of Afghanis population of O. tipulae is similar to those reported by Abolafia and Peña-Santiago (2019). This is the first record of O. tipulae from Afghanistan.

Figures

FIGURE 4. Oscheius tipulae. A: Lateral view of the tail region. B: Lateral view of the vulva region and lateral field. C: Pharyngeal region. D: Entire body.

FIGURE 5. Oscheius tipulae (scanning electron micrographs).A; A face view of head showing annulus; B: Head and lip region; C: anus and bacteria; D: Vulva.