Campylaimus amphidialis, Fadeeva, Natalia, Mordukhovich, Vladimir & Zograf, Julia, 2016

Fadeeva, Natalia, Mordukhovich, Vladimir & Zograf, Julia, 2016, RevIsIon of the genus Campylaimus (DIplopeltIdae, Nematoda) wIth descrIptIon of four new specIes from the Sea of Japan, Zootaxa 4107 (2), pp. 222-238 : 231-233

Campylaimus amphidialis sp. nov.

( Fig. 6 )

Locality: Table 1 .

Measurements. Table 4 .

Material examined. Holotype. Adult female, formalin-fixed, mounted on slide (MN A373-5), in glycerin. Paratypes. Two females, slides (A373-5 and A372-2), same data as holotype.

Etymology. The species name is derived from the Greek “amphid”.

Description. Female. Medium-sized, thread-like worms, uniformly cylindrical over most of length, with a clearly visible cuticular cephalic cap. Body narrows at both extremities. Cuticle with very weak annulations; anterior-most annule appears posterior to amphid and cephalic sensilla bases.

Oral opening subterminal, displaced on dorsal side of the body. Six inner labial papillae not seen. Four cephalic setae (2 µm) long, latero-dorsal pair located a little posterior to latero-ventral pair.

Amphids well developed, with unequal limbs. Dorsal short limb of amphid connects with ventral limb anterior to the oral opening. Long ventral limb (107 µm in holotype) extending to middle or the end of the pharynx, imperceptibly transforming into the narrow lateral alae extending along length of the body, terminating near tail tip. Amphidial fovea width 3.5–4 µm; lateral alae width 1.2–2 µm. Boundary between ventral amphid limb and lateral alae is well-defined. Long ventral limb of amphid extends to end of the cylindrical, weakly developed pharynx. Nerve ring surrounds posterior part of pharynx. Large well-developed amphidial glands.

Buccal cavity small, cylindrical, displaced dorsally and weakly sclerotized. Pharynx cylindrical, typical generic construction; nerve ring shifted to posterior end. Cardia small. Renette body not seen.

Female gonads paired, opposed; ovaries outstretched, not reflexed. Anterior and posterior ovaries located on the left and right side of intestine, respectively. Vulva a transverse slit, post equatorial (V= 52–56%). Vagina short, not thickened. Two glands surround the vulva.

Male. Not collected.

Diagnosis. Campylaimus amphidialis sp. nov. is characterized by having a very long ventral limb of the amphidial fovea, which occupies nearly the entire length of the pharynx (75–110 µm) and is wider than the lateral alae.

Differential diagnosis. Campylaimus amphidialis sp. nov. differs from all other valid species of the genus by having a very long ventral limb of the amphidial fovea which is separated from a narrow lateral alae.

In body size, the new species resembles C. gerlachi , but differs from it by having a shorter tail (4.2–4.7 vs 6.6–6.7 a.b.d., respectively) and in amphid form. Campylaimus amphidialis sp. nov. differs from C. tkatchevi by having narrower lateral alae (1–2 µm vs 13 µm (female), respectively).

Figures

FIGURE 6. Campylaimus amphidialis sp. nov. A: Entire body, female holotype; B: Posterior end of female. Scale bar: A = 100 µm; B = 50 µm.

Tables

TABLE 4. Measurements (Μm) of Campylaimus amphidialis sp. nov. (range)

	HOLOTYPE Female	PARATYPES Females N =2
L Maximum body diameter	608 38.0	498.8–537.8 38.9–41.0
Buccal cavity, length	4.0	3.0–4.0
Head diameter	9.0	7.0–9.0
Cephalic setae, length	2.0	2.0
Dorsal limb of amph. fovea length amph%	34.0	25.0–35.0
Ventral limb of amph. fovea length	107.0	75.0–110.0
Amphidial fovea width	3.0	3.0
Lateral alae	2.0	1.0–2.0
Pharynx, length	110.8	108.0–115.0
Tail, length	110.3	80.0–89.0
Anal body diameter	23.2	18.8–20.0
a	12.9	12.2–13.2
b c V, %	5.5 6.0 56	4.6–4.7 6.0–6.2 52–54