(No common name)

ORDER

Caryophyllidea

FAMILY

Caryphyllaeidae

TAXONOMY

Taenia laticeps Pallas, 1781, Russia.

OTHER COMMON NAMES

None known.

PHYSICAL CHARACTERISTICS

Body monozoic, longitudinally elongate, 0.79–1.6 in (20–40 mm) long and 0.04–0.08 in (1–2 mm) wide. Anterior end wider, forming some folds. Male genital pore and female genital pore situated on the ventral surface of the body at some distance from its posterior end.

DISTRIBUTION

North Eurasia, in Europe, Siberia, Central Asia, and Russian Far East.

HABITAT

Originally described as a parasite of the common bream (Abramis brama). Known also from about 30 species of freshwater fishes, mostly of the family Cyprinidae. Recorded also in some predatory fishes belonging to other families (e.g., pike and perch). Larvae recorded in tubificid annelids. The macrohabitats are slow rivers, lakes, ponds, marches, reservoirs, etc.

FEEDING ECOLOGY AND DIET

Internal parasite absorbing nutrients through the tegument.

BEHAVIOR

Nothing is known.

REPRODUCTIVE BIOLOGY

Caryophyllaeus laticeps is hermaphroditic. Eggs released with feces of the final hosts (fishes) need to stay in water for about three months in order to become infective. Intermediate hosts (aquatic tubificids) become infected by eating them. The oncosphere hatches in the intestine and penetrates into the body cavity. The larva develops for about six months. When fully developed, it is about 0.08 in (2 mm) long, with primordia of reproductive organs. Eating tubificids containing larvae infects fishes.

CONSERVATION STATUS

Not listed by the IUCN.

SIGNIFICANCE TO HUMANS

Together with another parasite of the same genus (C. fimbriceps), C. laticeps may cause a disease of farmed carps known as caryophyllaeasis. If parasites are few, they are not pathogenic for the host. It is believed that about 20 parasites per fish may cause some disorders of the digestive system and anemia.