Camallanus waelhreow

Hosts and localities

Originally described from Emydura krefftii, Emydura macquarii and Emydura macquarrii dharra in QLD (Rigby et al., 2008).

Present study:

Emydura macquarii - Mungabareena Reserve, Albury (NSW); Halpine Dam, Brisbane; UQ Farm Dam, Brisbane; Norfolk Lake, Brisbane; Leslie Dam, Warwick; MacIntyre Br, Inglewood (QLD).

Chelodina expansa - Mungabareena Reserve, Albury (NSW).

Description

Based on 25 specimens: 15 males and 10 females.

General. Slender worms. Body cuticle finely transversely striated. Head end truncated, tail end tapering. Oral opening narrow, slit-like. Eight circumoral papillae present: 4 minute inner and 4 large, rounded outer. Buccal capsule typical for the genus. Each valve of the capsule usually bears 9 inner ridges: 1 median ridge, 4 ventral and 4 dorsal ridges. The ridges run almost parallel to each other. In some specimens 1 or 2 ridges may be interrupted (Figs 2 - 5). Rarely number of ridges is 10 or 11, with one or two additional ridges. Median ridge is usually somewhat longer than the other ones. Rarely median ridge is short, about half as long as other ridges. All other ridges are almost equal in length, excepting the ventral and dorsal pairs, which are shorter than the others. Thick sclerotized ring present at base of buccal capsule. Tridents prominent, with posterior ends slightly behind level of anterior end of esophagus. In some specimens additional short protuberance may be present near median branch of trident (see Fig. 6). Muscular esophagus with prominent posterior bulb. Glandular esophagus about 1.5 times longer than muscular one. Three large nuclei present at posterior end of glandular esophagus. Intestine straight, narrow. Rectum thin-walled.

Males. Posterior part of body coiled ventrally. Testis straight, its anterior portion reflexed. Spicules unequal. Right spicule (Fig. 9) more sclerotized, with funnel-shaped capitulum and sharply pointed end. Posterior part needle-shaped, slightly curved ventrally. A short thorn-like process present on dorsal side of the spicule closer to its posterior end. Left spicule shorter, less prominent, with inconspicuous capitulum and sharply pointed end. Short sublateral genital alae bearing 7 pairs of preanal and 3 pairs of postanal papillae (Fig. 8). First two postanal papillae close to each other. A pair of lateral papillae situated closer to tail end. Tail conical, with rounded end.

Females. In gravid females uteri containing first-stage larvae occupy most of body cavity, from the middle of glandular esophagus till caudal part. Vulva inconspicuous, with no prominent inflation of body wall beside. Tail conical, elongated, often with minute dorsal protuberance close to tip (Fig. 10). Phasmids situated at midlength of tail.

Table 1. Morphometry. Measurements in micrometers unless otherwise indicated.
Mean value is followed by limits in parentheses.

Illustrations

Figure 1. Camallanus waelhreow 1 - Anterior end, lateral view. 2 - Head end, lateral view. 3 - Tail end of male, lateral view. 4 - Tail end of female, lateral view. Scale bars 0.1 mm.

Figure 2. Camallanus waelhreow, anterior end (lateral view) with usual number and shape of ridges in the buccal capsule. Scale bar 0.1 mm	Figure 3. Camallanus waelhreow, the buccal capsule with one interrupted ridge. Scale bar 0.1 mm

Figure 4. Camallanus waelhreow, the buccal capsule with two interrupted ridges. Scale bar 0.1 mm	Figure 5. Camallanus waelhreow, the buccal capsule with 3 anterior and two posterior incomplete ridges. Scale bar 0.1 mm

Figure 6. Camallanus waelhreow, the buccal capsule with a bifurcated ridge. Scale bar 0.1 mm	Figure 7. Camallanus waelhreow, anterior end. Dorsal view showing trident with a small additional prong. Scale bar 0.1 mm

Figure 8. Camallanus waelhreow, male tail (lateral view) with 7 pairs of preanal genital papillae (1 - 7). Scale bar 0.5 mm.	Figure 9. Camallanus waelhreow, male tail (lateral view) with a prominent right spicule. Scale bar 0.5 mm.
Figure 10. Camallanus waelhreow, female tail (lateral view). Arrow indicates a small dorsal process close to the tail tip. Scale bar 0.1 mm.

Authors: Vasyl V. Tkach, Scott D. Snyder, Yuriy Kuzmin