Enterobius (Colobenterobius) emodensis, 2018

Hasegawa, Hideo, Nautiyal, Himani, Sasaki, Mizuki & Huffman, Michael A., 2018, Description of Enterobius (Colobenterobius) emodensis sp. n. (Nematoda: Oxyuridae) collected from Central Himalayan langur, Semnopithecus schistaceus, in Uttarakhand, India, Zootaxa 4514 (1), pp. 65-76 : 66-69

Enterobius (Colobenterobius) emodensis sp. n.

( Figs. 1–22 )

General: Body light brown in color. Cephalic expansion well developed, with internal septa in posterior half ( Figs. 1, 2 , 8 ). Cuticle with transverse striations. Lateral alae single crested, triangular in cross section ( Figs. 4 , 12 ). Cephalic end with 3 developed lips; dorsal lip with 2 cephalic papillae, subventral lips each with cephalic papilla and amphidial pore ( Figs. 3 , 10 ). Pharyngeal teeth with lamellated superstructures, corresponding to one-third of lip width in apical view (Figs, 3, 10); slots with cuticular wall extending to the posterior one-fourth of pharynx (Fig, 11). Esophageal corpus long club-shaped, with posterior one-third darker containing granules in wall ( Figs. 1, 2 , 8 ); short esophageal isthmus present but often hardly discernible in fully gravid females; esophageal bulb valved.

Male (Holotype and 10 paratypes): Body tapered to anterior end; posterior body bent ventrally, forming coils ( Fig. 1 ). Length 2.61 (2.01–2.90) mm; maximum width 183 (143–216). Distance between amphidial pores 40. Lateral alae commencing at level slightly posterior to nerve ring, terminating at level anterior to caudal alae ( Figs. 2, 5 ). Cephalic expansion 161 (123–186) long by 89 (75–97) wide. Pharynx 29 (28–32) long; esophageal corpus 431 (355–464) long by 66 (51–79) wide; isthmus 5 (3–6) long by 21 (18–24) wide; bulb 123 (91–135) long by 113 (95–125) wide. Total esophagus length including pharynx, corpus, isthmus and bulb 587 (480–620), corresponding to 22.5 (21.1–24.0) % of worm length. Nerve ring 157 (141–167) and excretory pore 795 (657–976) from cephalic apex. Caudal alae supported by 4 pairs of papillae: 1 st pair precloacal, pedunculate, large, directing laterally; 2 nd and 3 rd pairs near cloacal aperture, sessile, small, directing ventrally; 4 th pair pedunculate, directing posterolaterally; phasmidial pore near base of 4 th pair ( Figs. 5, 6 ). Testis directing anteriorly ( Fig. 1 ). Distal portion of testis filled with round spermatozoa each with ca. 2.5 diameter. Spicule slender, 223 (197–238) long, arched, bending ventrally distally, proximal end with light-refractive mass; portion protruding from the cloacal aperture often covered with dark material ( Figs. 5–7 ). Relationship between worm length and spicule length shown in Fig. 23 .

Female (Allotype and 11 paratypes): Body tapered to both extremities. Length 7.51 (7.15–8.10) mm, maximum width 428 (360–488). Distance between amphidial pores 42. Lateral alae commencing at level slightly posterior to nerve ring, terminating at middle of tail. Cephalic expansion 243 (204–257) long by 129 (106–143) wide. Pharynx 35 (32–36) long; esophageal corpus 739 (680–776) long by 103 (90–114) wide; isthmus 3 (2–4) long by 26 (24–28) wide (n=5); bulb 168 (162–178) long by 160 (147–172) wide. Total esophagus length 926 (796–992), corresponding to 12.4 (10.7–13.7) % of worm length. Nerve ring 210 (184–249), excretory pore 1.15 (0.94–1.32) mm (n=5) from cephalic apex. Distance from cephalic apex to vulva 1.88 (1.60–2.14) mm, corresponding to 25.0 (21.5–28.7) % of worm length ( Fig. 8 ). Muscular vagina thick, directing posteriorly; vagina uterina with thick epithelium, about twice as long as muscular vagina; cellular wall present dividing length from vagina and opening to uterus ca. 3:1; amphidelphic; uterus of young gravid females filled with dark material, vagina uterina just before cellular wall containing mass of minute round structures each with ca. 2.5 diameter ( Fig. 13 ). Tail slender, gradually tapering to sharp point, 1.49 (1.25–1.73) mm long, occupying 19.8 (16.8–21.6) % of worm length ( Fig. 9 ). Phasmidial pore opening on lateral ala at level slightly posterior to anus. Eggs with one side flattened, 60.6 ± SD 1.2 (59–63) by 27.1 ± SD 0.6 (26–28) (n=25), convex side with operculum-like structure near pole ( Fig. 14 ).

Figures

FIGURE 23. Relationship of spicule length to worm length in males (Approximation formula: y = 14.725x + 191.94; n=112).

FIGURES 1–7. Male of Enterobius (Colobenterobius) emodensis sp. n. collected from Semnopithecus schistaceus in Chamoli District, Uttarakhand, India. 1. Holotype, left lateral view. 2. Enlarged view of anterior portion of holotype, left lateral view. 3. Cephalic end, apical view. 4. Lateral ala in cross section. 5. Posterior portion of holotype, left lateral view. 6. Caudal end, ventral view. 7. Spicule.

FIGURES 8–14. Female of Enterobius (Colobenterobius) emodensis sp. n. collected from Semnopithecus schistaceus in Chamoli, Uttarakhand, India. 8. Anterior portion of allotype, left lateral view. 9. Posterior portion of allotype, left lateral view. 10. Cephalic end, apical view. 11. Cephalic apex sectioned. 12. Lateral ala in cross section. 13. Ovejector, right lateral view. 14. Egg.

FIGURES 15–20. Fourth-stage larvae of Enterobius (Colobenterobius) emodensis sp. n. collected from Semnopithecus schistaceus in Chamoli, Uttarakhand, India. 15. Cephalic apex of female, apical view. 16. Anterior portion of male, right lateral view. 17. Posterior portion of male, right lateral view. 18. Anterior portion of female, right lateral view. 19. Posterior portion of female, right lateral view. 20. Anterior portion of premolt female, right lateral view.

FIGURES 21, 22. Reproductive organs of immature adult females of Enterobius (Colobenterobius) emodensis sp. n. collected from Semnopithecus schistaceus in Chamoli District, Uttarakhand, India. 21. Ventral view (in worm of 2.48 mm long). 22. Right lateral view (in worm of 3.95 mm long).