Tylencholaimus intermedius Peña-Santiago and Coomans, 1996

Ahmad, Wasim, Park, Byeong-Yong, Lee, Jae-Kook & Choi, Dong-Ro, 2009, Some new and known species of Tylencholaimoidea (Nematoda: Dorylaimida) from Korea, Journal of Natural History 43 (37 - 38), pp. 2329-2356 : 2338

Tylencholaimus intermedius Peña-Santiago and Coomans, 1996

( Figures 4F–J , 5F–H ; Table 3)

Description

Female. Lip region cap-like, rather flattened, offset by slight constriction, about twice as wide as high. Lips amalgamated; labial papillae not interfering with the labial contour. A weakly developed post-labial sclerotization present. Amphids small, cup-shaped, their aperture about one-third of corresponding body width. Odontostyle relatively slender, about as long as lip region width; its aperture about one-third of its length. Guiding ring single, at 0.76 times the lip region width from anterior end. Odontophore rod-like, 1.14 times the odontostyle length, practically without basal knobs. Anterior part of pharynx slender, weakly muscular, expanding abruptly into a long cylindrical basal bulb, occupying about 40% of total neck length. Cardia short conoid. Genital system monodelphic–opisthodelphic; anterior genital branch completely absent. Vagina somewhat pyriform, extending inward and backward to about one-third of the corresponding body width. Vulva a transverse slit. Tail short, hemispheroid, rather cylindrical with a weak terminal caudal pore.

Male. Not found.

Habitat and locality

Soil around roots of forest trees from Jincheon forest, Jincheon-gun, Gyeongi-do, South Korea.

Remarks

Tylencholaimus intermedius Peña-Santiago and Coomans, 1996 is an interesting species of the genus Tylencholaimus with the shape of its lip region, post-labial thickening, almost absence of basal knobs and DN situated rather posteriorly, quite uncommon for the species in this group. Peña-Santiago and Coomans (1996) described this species from Spain. Ahmad and Araki (2003) recorded two females of this species from Japan while a single specimen was recovered from Jincheon forest during our present study. The Korean specimen is similar to Spanish and Japanese specimens. We also noted a distinct hemizonid in our specimen similar to the one recorded in Japanese specimens. Hemizonid was not recorded in Spanish specimens.

Figures

Figure 4. (A–E) Tylencholaimus sp. (A) Anterior region; (B) anterior end showing amphid; (C) expanded part of pharynx; (D) female genital system; (E) female posterior region. (F–J) Tylencholaimus intermedius Peña-Santiago and Coomans, 1996. (F) Anterior end; (G) anterior end showing amphid; (H) expanded part of pharynx; (I) female genital region; (J) female posterior region.(K–O) Promumtazium pyxidorum Siddiqi, 1982. (K) Anterior region; (L) anterior end showing amphid; (M) expanded part of pharynx; (N) female genital system; (O) female posterior end.

Figure 5. (A–E) Tylencholaimus sp. (A) Anterior region; (B) expanded part of pharynx; (C) female genital system; (D) female posterior region: (E) female posterior end. (F–H) Tylencholaimus intermedius Peña-Santiago and Coomans, 1996. (F) Anterior region; (G) expanded part of pharynx; (H) female genital system.