Ascarophis arctica Polyanski, 1952

Arai, Hisao P. & Smith, John W., 2016, Guide to the Parasites of Fishes of Canada Part V: Nematoda, Zootaxa 4185 (1), pp. 1-274 : 84-86

Ascarophis arctica Polyanski, 1952

Description (after Appy 1981). With characteristics of the genus.

Males: 6.6 (5.7–7.9) long, 0.089 (0.062–0.105) wide at vas deferens. Muscular oesophagus 0.274 (0.233– 0.325) and glandular oesophagus 1.650 (1.325–2.045) long. Deirids, nerve ring and excretory pore 0.132 (0.110– 0.151), 0.179 (0.155–0.202) and 0.267 (0.232–0.338), respectively, from anterior end ( Fig. 52 A). Tail 0.151 (0.129–0.182) long. Right spicule 0.100 (0.085–0.111) long, spicule arcuate, notched distally. Left spicule 0.808 (0.585–0.882) long, tubular, divided into proximal shaft and blade. Ratio of left to right 1:8.1 (1:5.9 to 1:10.4).

Area rugosa with about 14 longitudinal rows of cuticular elevations. Ten pairs caudal papillae: two double pairs pre-cloacal, six pairs post-cloacal; 5th post-cloacal pair relatively small, ventral to 6th pair. Caudal alae narrow. Phasmids immediately behind last pair post-cloacal papillae ( Fig. 52 B).

Females: 13.3 (10.5–15.4) long, 0.124 (0.092–0.157) wide at vulva. Muscular oesophagus 0.321 (0.235–0.414)

and glandular oesophagus 1.928 (1.474–2.554) long. Deirids, nerve ring, excretory pore and vulva 0.147 (0.131–

0.166), 0.194 (0.172–0.221), 0.295 (0.269–0.338) and 7.0 (5.5–8.3), respectively, from anterior end ( Fig. 52 C).

[NB: to avoid clutter in Figure 52 C the in utero eggs have been drawn as if they lack polar filaments.] Tail 0.052

(0.034–0.071) long. Eggs 0.045 (0.043–0.048) x 0.024 (0.022–0.027) with filaments at both poles ( Fig. 52 D). [For comments on A. arctica see page 90–91]

Sites: alimentary tract, stomach

Hosts: Gadus morhua (1, 3); Hemitripterus americanus (1); Hippoglossoides platessoides (5); Melanogrammus aeglefinus (1, 2, 4); Merluccius bilinearis (1); Microgadus tomcod (1); Osmerus mordax (1); Pholis gunnellus (1); Pseudopleuronectes americanus (1, 7); Reinhardtius hippoglossoides (6); Urophycis tenuis (1); Zoarces americanus (1)

Distribution: Atlantic

Records: 1. Appy 1981; 2. Scott 1981; 3. Appy & Burt 1982; 4. Scott 1982; 5. Zubchenko 1985a; 6. Arthur & Albert 1994; 7. McClelland et al. 2005

Figures

FIGURE 52. Ascarophis arctica Polyanski, 1952. A. male, anterior end, lateral view; B. male, posterior end, ventral view, arrows indicate the 5 th and 6 th pairs of post-caudal papillae; C. female, vulvar region, lateral view [NB: for presentational reasons, polar filaments have been omitted from in utero eggs to avoid clutter]; D. egg from uterus. (Redrawn from Appy 1981)