TY - JOUR

T1 - Possible progenesis in Neophasis anarrhichae (Nicoll, 1909) Bray, 1987 in the White Sea

AU - Krupenko, Darya

AU - Kremnev, Georgii

AU - Krapivin, Vladimir

PY - 2019/6/1

Y1 - 2019/6/1

N2 - Neophasis anarrhichae (Nicoll, 1909) Bray, 1987, unlike the majority of acanthocolpid digeneans, has an abbreviated two-host life cycle. The reproduction of rediae, development of cercariae, and their transformation into unencysted metacercariae occur within the only intermediate host, the whelk Buccinum undatum. Normally, the metacercariae develop into sexual adults (maritae) and egg production starts when the infected whelk is eaten by a wolffish Anarhichas lupus. In the White Sea, we have found three cases of infection of B. undatum by progenetic metacercariae of N. anarrichae. These metacercariae had a fully developed and functioning hermaphroditic reproductive system, and eggs were found in their uterus. Most eggs observed in the histological sections were abortive, but some contained embryos at early stages of development. The progenetic metacercariae were similar in their morphometric characteristics to the sexual adults from the wolffish, the main differences being the size of the ovary and eggs. In order to confirm progenesis, and thus a facultative one-host life cycle in N. anarrichae, we need to prove that the eggs from metacercariae are viable.

AB - Neophasis anarrhichae (Nicoll, 1909) Bray, 1987, unlike the majority of acanthocolpid digeneans, has an abbreviated two-host life cycle. The reproduction of rediae, development of cercariae, and their transformation into unencysted metacercariae occur within the only intermediate host, the whelk Buccinum undatum. Normally, the metacercariae develop into sexual adults (maritae) and egg production starts when the infected whelk is eaten by a wolffish Anarhichas lupus. In the White Sea, we have found three cases of infection of B. undatum by progenetic metacercariae of N. anarrichae. These metacercariae had a fully developed and functioning hermaphroditic reproductive system, and eggs were found in their uterus. Most eggs observed in the histological sections were abortive, but some contained embryos at early stages of development. The progenetic metacercariae were similar in their morphometric characteristics to the sexual adults from the wolffish, the main differences being the size of the ovary and eggs. In order to confirm progenesis, and thus a facultative one-host life cycle in N. anarrichae, we need to prove that the eggs from metacercariae are viable.

KW - Acanthocolpidae

KW - Digenea

KW - Life cycle abbreviation

KW - Neophasis

KW - Progenesis

KW - PARASITES

KW - TREMATODE

KW - LIFE-CYCLE ABBREVIATION

UR - http://www.scopus.com/inward/record.url?scp=85062180218&partnerID=8YFLogxK

U2 - 10.1016/j.parint.2019.02.007

DO - 10.1016/j.parint.2019.02.007

M3 - Article

AN - SCOPUS:85062180218

VL - 70

SP - 82

EP - 85

JO - Parasitology International

JF - Parasitology International

SN - 1383-5769

ER -