Rhinebothrium walga (Shipley et Hornell, 1906) parasite in collection sequenced

Other host

Dasyatis pastinaca (Linnaeus, 1758)

Other localities

Black Sea, Streletskaya Bay, Sevastopol; Black Sea, Cape Sarich, Sevastopol

Description

Based on 5 immature specimens, 15 complete mature and 3 separate scolex.
Worms euapolytic, 0,94–4,72 (2,1 ± 0,2; n = 20) mm long, 0,08–0,75 (0,16 ± 0,02; n = 48) mm wide; proglottids acraspedote, 17–48 (32 ± 2,3; n = 16) per mature worm. Scolex composed of 4 stalked, facially loculate bothridia and cephalic peduncle; apical organ absent. Bothridia 375–938 (535 ± 25; n = 28) long, a maximum width of 90–313 (140 ± 8; n = 28) closer to their anterior and posterior ends. Distal bothridial surface divided by median longitudinal septum and 17−21 (20,5 ± 0,2; n = 35) transverse septa delimiting 2 columns of 16−20 (19,5 ± 0,2; n = 35) loculi per column and anterior single loculus, resulting a total of 34−42 (41 ± 0,3; n = 35) loculi per bothridium; longitudinal septum extending from posterior margin of anterior most loculus to posterior margin of bothridium. Anterior most loculus single, 10–70 (35 ± 1,7; n = 37) long, 25–80 (52 ± 2,5; n = 38) wide. Posterior most loculi 25–50 (36 ± 1,5; n = 32) long, 25–80 (54 ± 3; n = 32) wide. The widest locules are located closer to the posterior and anterior ends of the botridium, 50–781 (120 ± 24; n= 30). Bothridial stalks 80–330 (164 ± 9; n = 40) long, attached to middle of proximal bothridial surface. Cephalic peduncle 90–250 (140 ± 9; n = 23) long, 90 – 219 (127 ± 7; n = 23) wide. Immature proglottids wider than long, 40–110 (72 ± 5; n = 23) long, 75–250 (134 ± 8; n = 23) wide; mature proglottids longer than wide, 80–207 (207 ± 26; n = 19) long, 80–250 (137 ± 10; n = 19) wide; length to width ratio 0,83−2,71 (1,8 ± 0,1; n = 15): 1. Marginal genital pores alternate irregularly, 57–72 % (62 ± 1,2; n= 21) from posterior margin of proglottid. Terminal proglottids mature, longer than wide, 120–625 (286 ± 27; n = 26) long, 90–188 (139 ± 5,5; n= 26) wide; length to width ratio 1,1−4,2 (2,23 ± 0,2, n = 20): 1. Testes oval, 3–5 (4,3 ± 0,1; n = 20) per proglottid, 10–63 (31 ± 3,2; n = 25) long, 19–63 (37 ± 2,4; n = 25) wide, extending from near anterior margin of proglottid to anterior margin of cirrus sac, 1 row deep in cross-section. Cirrus sac pyriform, curved posteriorly, 30–94 (57 ± 4; n = 19) long, 30–63 (46 ± 3; n = 19) wide, containing cirrus covered by spinitriches. Vas deferens extending medially to the posterior margin of the proglottid and forming several loops at the posterior margin of cirrus sac, near poral lobe ovary, maximum, width 10–25 (21 ± 1,3; n = 15). The genital atrium is very deep, 20–50 (32 ± 2; n = 20) long, 10–63 (30 ± 4; n = 20) wide. The vagina is thin-walled, opening anterior to cirrus sac in genital atrium, extends along anterior margin of cirrus sac, descending posteriorly to ootype region. Ovary occupies posterior third of proglottid, lobulated, U-shaped in dorsoventral view, tetra-lobed in cross-section at level of ovarian isthmus, maximum width at level of isthmus 20–60 (38 ± 3; n = 21), symmetric, 50–220 (128 ± 12; n = 21) long. Vitelline follicles round, 6–25 (14 ± 1,3; n = 18) in diameter, distributed in columns of 2 follicles deep (1 dorsal, 1 ventral) on each side of proglottid, interrupted dorsally on poral side at level of terminal genitalia, not interrupted by the ovary. Mehlis’ gland 10–31 (18 ± 2; n = 19) in diameter, posterior to ovarian isthmus. Uterus saccate, visible in mature proglottids; extending to near posterior margin of proglottid and anteriorly to near anterior margin of proglottid. Eggs not found

Bibliography

First published in

Polyakova T. A. 2006. The first description of morphology cestoda Rhinebothrium walga (Tetraphyllidea, Phyllobothriidae) from Dasyatis pastinaca in the Black Sea. Vestnik zoologii, 40 (1), P. 71-75. (in Russian)

Nucleotide sequences

Specimens in collection