Camallanus oxycephalus Ward & Magath, 1917

Arai, Hisao P. & Smith, John W., 2016, Guide to the Parasites of Fishes of Canada Part V: Nematoda, Zootaxa 4185 (1), pp. 1-274 : 62-64

** Camallanus oxycephalus Ward & Magath, 1917

Description (after Stromberg et al. 1973). With characteristics of the genus.

Slender worms, widest in middle third of body and tapering slightly towards tail. Living worms red in colour. Cuticle with barely perceptible striae. Head straight, not bent ventrally. Mouth opening elongate. Buccal capsule divided into two sclerotized lateral valves with smooth longitudinal rib-like thickenings internally; inflation of valves forms sclerotized ring at junction of buccal cavity and oesophagus. Two trident-shaped processes at junction of valves, one dorsal, one ventral ( Fig. 40 A). Three pairs of simple circumoral papillae in outer circle; two pairs in inner circle at dorsal and ventral ends of mouth opening. Oesophagus with anterior club-shaped muscular portion, and posterior cylindrical glandular portion. Intestine straight. Anal lips slightly protruding.

Males: 4.57 (4.43–5.20) long; width 0.15 (0.12–0.18). Buccal capsule 0.103 (0.096–0.112) by 0.100 (0.096– 0.107). Tridents 0.094 (0.086–0.104) long. Muscular oesophagus 0.390 (0.360–0.422), and glandular oesophagus 0.461 (0.428–0.530) long. Nerve ring 0.168–0.210 from anterior end. Single testis reaching almost to glandular oesophagus, then reflexed; reproductive tract with several swollen portions separated by constrictions. Tail 0.121 (0.109–0.136) long, rolled ventrally in mature worms, ending bluntly without a mucron. Thin caudal alae supported by papillae. Six pairs pre-cloacal, five pairs post-cloacal papillae. Spicules unequal but similar, left one weakly sclerotized, right one heavily so, 0.154 (0.146–0.166) long. Gubernaculum absent ( Fig. 40 B).

Females: 18.18 (15.93–25.05) long. Buccal capsule 0.137 (0.128–0.142) by 0.151 (0.136–0.165). Tridents 0.138 (0.134–0.144) long. Muscular oesophagus 0.569 (0.483–0.666), glandular oesophagus 0.652 (0.558–0.748) long. Nerve ring 0.262 (0.222–0.300) from anterior end. Vulva 2.24–3.11 from tail tip, lips slightly protruding. Vagina very muscular, directed posteriorly. Single ovary reaching level of muscular oesophagus, then reflexing; posterior branch of uterus reaching tail end, ending blindly in an highly muscular sac. Tail 1.87 (1.53–2.21) long, bluntly rounded without mucron ( Fig. 40 C). Ovoviviparous: larvae 0.635 (0.629–0.645) long.

Site: intestine

Hosts: Ambloplites rupestris (1, 2, 7); Ameiurus nebulosus (4); Ammocrypta pellucida (1); Aplodinotus grunniens (1, 9); Carpiodes cyprinus (4, 9); Catostomus commersonii (3, 6); Cottus bairdii (3); Culaea inconstans (3); Cyprinella spiloptera (1); Esox lucius (7); Etheostoma blennioides (1); Etheostoma exile (3, 7); Fundulus diaphanus (7); Hiodon tergisus (1); Ictalurus punctatus (1); Labidesthes sicculus (1); Lepomis gibbosus (1, 7); Lepomis macrochirus (7); Lota lota (3); Micropterus dolomieu (1, 2, 3, 7, 8, 9, 10, 11); Micropterus salmoides (1); Morone chrysops (1, 2, 9); Notemigonus crysoleucas (7, 12); Notropis atherinoides (1); Notropis buccatus (1); Notropis heterodon (1); Notropis heterolepis (1); Notropis hudsonius (1); Notropis stramineus (1); Noturus flavus (1); Oncorhynchus kisutch (7); Perca flavescens (1, 3, 9); Percina caprodes (1, 3, 7); Percina copelandi (1); Percina maculata (1); Percopsis omiscomaycus (1); Pomoxis nigromaculatus (1, 2, 7); Rhinichthys cataractae (1); Salmo salar (5); Sander canadensis (1, 3); Sander vitreus (1, 9)

Distribution: Nova Scotia, Ontario

Records: 1. Bangham & Hunter 1939 (ON); 2. Bangham 1955 (ON); 3. Dechtiar 1972a (ON); 4. Dechtiar 1972 b (ON); 5. Hare & Frantsi 1974 (NS); 6. Chan 1980 (ON); 7. Dechtiar & Christie 1988 (ON); 8. Dechtiar & Lawrie 1988 (ON); 9. Dechtiar & Nepszy 1988 (ON); 10. Dechtiar et al. 1988 (ON); 11. Dechtiar et al. 1989 (ON); 12. Forest & Cone 2011 (ON)

Figures

FIGURE 40. Camallanus oxycephalus Ward & Magath, 1917. A. adult, buccal capsule, lateral view; B. male, posterior end, ventral view; C. female, posterior end, lateral view. (A. redrawn from Stromberg & Crites 1974; B. and C. redrawn from Stromberg et al. 1973)