Dorylaimellus (Axodorylaimellus) hanifae, Ahmad & Naz, 2012

Ahmad, Wasim & Naz, Tabbasam, 2012, Four new and six known species of the genus Dorylaimellus Cobb, 1913 (Nematoda: Belondiridae) from India, Journal of Natural History 46 (45 - 46), pp. 2787-2828 : 2797-2801

Dorylaimellus (Axodorylaimellus) hanifae sp. nov.

( Figures 5 and 6 ; Table 3)

Description

Female. Body curved ventrad upon fixation, tapering towards both extremities. Cuticle with transverse striations, 1.5–2.0 µm thick at mid body and 5–7 µm on tail. Lateral chords about one-quarter as wide as body width at mid body. Lateral, dorsal and ventral body pores indistinct. Lip region distinctly offset by constriction, about twice as wide as high or about one-third as wide as body width at neck base; peri-oral disc present. Amphids stirrup-shaped, their aperture about 0.8 times the lip region width. Cheilostome a truncate cone with refractive walls and comparatively weakly developed cuticularized plates. Odontostyle slender, about 1.0–1.2 times the lip region width long, its aperture about one-third of its length. Odontophore poorly flanged, 2.0–2.5 times the odontostyle length. Nerve ring at 35–38% of neck length from anterior end. Pharyngeal expansion abrupt; expanded part occupying about 50–55% of total neck length, enclosed in a thick sheath of dextrally spiral muscles. Cardia short, rounded, more than half of the corresponding body width long. Genital system amphidelphic, both the sexual branches almost equally developed. Ovaries reflexed, measuring 12–15 µm (anterior) and 13–15 µm (posterior) with oocytes arranged in a single row except near tip. Oviduct joining ovary subterminally measuring 13–18 µm (anterior) and 11–16 µm (posterior) long. Sphincter present at oviduct–uterus junction. Uterus a small tube, measuring 18–20 µm (anterior) and 12–16 µm (posterior). Vulva transverse; vagina extending inward, about one-third of corresponding body width; pars proximalis vaginae 4–5 µm with slightly convex walls; pars refringens vaginae absent; pars distalis vaginae 1.0– 1.2 µm with rounded walls. Prerectum 3.5–4.0 times anal body width long. Rectum about one anal body width. Tail clavate with thick cuticle, 1.4–1.7 times anal body width long. Caudal pores two on each side.

Male. Not found.

Type habitat and locality

From soil around the roots of shrubs and small trees of Tamu, near Indo-Mayanmar border, Manipur; 24 ◦ 19 ′ 0 ′′ N, 93 ◦ 59 ′ 0 ′′ E, altitude 967 m above sea level .

Type specimens

Holotype female on slide Dorylaimellus (A.) hanifae sp. nov. / 1; paratype females on slides Dorylaimellus (A.) hanifae sp. nov. / 2–4; deposited with the nematode collection of the Department of Zoology, Aligarh Muslim University, India. A paratype female deposited with the nematode collection of the Universidad de Jaén, Spain.

Etymology

The new species is named after Mrs Hanifa Begum, mother of the second author.

Diagnosis and relationships

Dorylaimellus (A.) hanifae sp. nov. is characterized by having 0.3–0.4 mm long body; offset lip region with peri-oral disc; slender, 4–5 µm long odontostyle,; expanded part of pharynx 50–55% of neck length; transverse vulva at 57–62%; amphidelphic female genital system and distinctly clavate tail with thick cuticle, 1.4–1.7 times anal body width long.

In having peri-oral disc and transverse vulva the new species belongs to the subgenus Axodorylaimellus Jairajpuri and Ahmad, 1980 and comes close to D. crassidens ( Siddiqi, 1983) Jairajpuri and Ahmad, 1992 but differs from it in having slightly shorter body (0.3–0.4 vs 0.5 mm), slender odontostyle (vs robust thick-walled odontostyle), tail distinctly clavate with thick cuticle, 1.4–1.7 times anal body width long (vs tail subclavate with less thick cuticle, two times anal body width long).

In having peri-oral disc and thickened tail cuticle, the new species also comes close to Dorylaimellus iari Siddiqi, 1983 , but distinctly differs in its tail shape (tail clavate with exceptionally thick cuticle vs hemispherical) and longer prerectum (3.5–4 vs 2.5–3.5 times anal body width long).

Figures

Figure 5. Dorylaimellus (Axodorylaimellus) hanifae sp. nov. (A) Entire female, (B) anterior region, (C) anterior end showing amphid, (D) pharyngeal region, (E) expanded part of pharynx, (F) female genital system, (G) vulva in ventral view, (H) female posterior region showing prerectum, (I) female posterior region.

Figure 6. Dorylaimellus (Axodorylaimellus) hanifae sp. nov. (A) Anterior region, (B) expanded part of pharynx, (C) female genital system, (D) female posterior region. Scale bars: A– D = 10 µm.