Huffmanela canadensis Moravec, Conboy & Speare, 2005

Arai, Hisao P. & Smith, John W., 2016, Guide to the Parasites of Fishes of Canada Part V: Nematoda, Zootaxa 4185 (1), pp. 1-274 : 34

Huffmanela canadensis Moravec, Conboy & Speare, 2005

Description (after Moravec et al. 2005). With characteristics of the genus.

Males (holotype measurements in parentheses): 3.441–3.862 (3.441) long, 0.045–0.063 (0.045) maximum width. Entire oesophagus 1.333–1.346 (1.333), muscular oesophagus 0.147–0.153 (0.153), and stichosome 1.180– 1.199 (1.180) long; 40–42 (42) stichocytes ( Fig. 25 A). Nerve ring 0.048–0.069 (0.069) from anterior end. Single testis reaches anteriorly to near oesophago-intestinal junction ( Fig. 25 B). Cloaca long (0.093 in holotype). Tail slightly narrowed, rounded, bearing pair of large pre-anal papillae. Cloacal aperture slightly depressed ( Fig. 25 C).

Females (allotype measurements in parentheses): gravid worms 7.711–8.160 (17.711) long, 0.090–0.105 (0.090) maximum width. Entire oesophagus 1.768–2.054 (1.768), muscular oesophagus 0.180–0.216 (0.210), and stichosome 1.558–1.838 (1.558) long; 32–37 (35) stichocytes. Nerve ring 0.075–0.078 (0.078) from anterior end. Vulva slightly posterior to oesophago-intestinal junction, anterior vulvar lip elevated ( Fig. 25 D). Vagina short. Ovary single, posteriorly extending to end of intestine. Colourless rectum 0.111 (0.099) long, anus terminal ( Fig. 25 E). In utero eggs with polar plugs, oval, light coloured, non-embryonated, shell appears two-layered ( Fig. 25 F). Eggs 0.032–0.039 x 0.024–0.027 (0.036–0.039 x 0.024–0.027). Eggs in anterior uterus arranged in one row, two to three rows posteriorly.

Advanced eggs in host skin are dark brown, oval, with two-layered wall, surface with many transverse, somewhat oblique, complete or incomplete ridges. Polar plugs light coloured, height 0.006–0.009. Eggs including the polar plugs 0.048–0.063 (mean 0.054) x 0.024–0.027 (mean 0.026) containing a fully formed larva ( Fig. 25 G,H).

Sites: skin of fins and adjacent skin

Hosts: Sebastes spp.

Distribution: Pacific

Records: Conboy & Speare 2002; Moravec et al. 2005

Figures

FIGURE 25. Huffmanela canadensis Moravec, Conboy & Speare, 2005. A. male, anterior end; B. male, oesophago-intestinal junction; C. male tail, ventral view; D. female, vulvar region; E. female tail, lateral view; F. most developed egg ex uterus; G. egg, dark, fully developed ex host tissue, showing surface ridges; H. egg, dark, fully developed, contains larva. (Redrawn from Moravec et al. 2005)