Shchenkov S.V.*, Denisova S.A., Nesterenko M.A., Lebedenkov V.V., Kharytonau D.E. 2022. Morphological description and phylogenetic position of xiphidiate cercaria of Prosthogonimus pellucidus (Trematoda: Digenea) // Invertebrate Zoology. Vol.19. No.4: 425–432 [in English].
Department of Invertebrate Zoology, St Petersburg State University, Universitetskaja emb., 7/9, St Petersburg, 199034, Russian Federation.
* Corresponding author: svshchenkov@yandex.ru
Sergei Shchenkov: ORCID 0000-0002-0579-1660
Sofia Denisova: ORCID 0000-0002-5602-5894
Maksim Nesterenko: ORCID 0000-0002-8807-1115
Vladimir Lebedenkov: ORCID 0000-0002-4870-6497
Dmitry Kharytonau: ORCID 0000-0001-5987-005X
doi: 10.15298/invertzool.19.4.06
ABSTRACT: Xiphidiocercariae is a non-taxonomic group of digenean larvae. These small cercariae are characterized by complex morphology, which complicates their accurate identification. Recently, we have devoted a series of papers to the least studied groups of xiphidiocercariae — Cercariae virgulae and Cercariae microcotylae. Here we present the morphological description and molecular phylogenetic analysis of the new microcotylous cercaria. We have identified morphological features that allow us to distinguish this larva from all previously described cercariae. This species lacks virgula organ and possesses three pairs of penetration glands and Y-shaped excretory bladder. Molecular phylogenetic analysis performed with 28S rDNA and cox1 mtDNA sequences made it possible to confirm the taxonomic position of this cercaria within the family Prosthogonimidae, and to determine its species identity as one of the least common adult digenean Prosthogonimus pellucidus.
KEY WORDS: Xiphidiocercariae, stylet cercaria, Plagiorchiida, penetration glands, Prosthogonimidae.