DNA sequencing demonstrates the importance of jellyfish in life cycles of lepocreadiid trematodes

摘要

Sequence data were combined with morphological analyses to identify two lepocreadiid trematode species from jellyfishes and fishes. Three species of jellyfish were captured within Port Phillip Bay, Australia, and three species of fish that feed on jellyfish were obtained from Moreton Bay (Queensland) and Port Phillip Bay and Portland (Victoria). The digeneans were distributed throughout most parts of the jellyfish.Opechonacf.kahawaiBray & Cribb, 2003 parasitized the scyphozoan jellyfishAequorea eurodinaand the scombrid fishScomber australasicus.Cephalolepidapedon warehouBray & Cribb, 2003 parasitized the scyphozoansPseudorhiza haeckeliandCyanea annaskala, and the centrolophid fishesSeriolella bramaandSeriolella punctata.Intensities ranged from four to 96 in the jellyfish, and one to 30 in the fish. For both trematode species, internal transcribed spacer 2 of ribosomal DNA sequences from mature adults in the fishes matched those from metacercariae from the jellyfish. This is the first record of larval stages ofC. warehouandO.cf.kahawai, and the first use of DNA sequencing to identify digenean trematode metacercariae from jellyfish. Three new host records are reported forC. warehouand two forO.cf.kahawai.