The sexual adult of Cercaria praecox Walker, 1971 (Digenea: Fellodistomidae), with the proposal of Oceroma n. g.

Abstract

A sexual adult trematode that is considered to be conspecific with the distinctive larval trematode Cercaria praecox Walker, 1971 is reported from the kyphosid fish Scorpis lineolata Kner in Moreton Bay, Queensland, Australia. The sexual adult is consistent with the cercarial body of Cercaria praecox in having a single caecum with an asymmetrical appendix, symmetrical testes immediately posterior to the ventral sucker, and the ovary and vitellarium both well posterior to the testes. This combination of characters is distinct within the Fellodistomidae Nicoll, 1909 and requires the proposal of a new genus, Oceroma n. g. Analysis of 28S rDNA sequences demonstrates that this species forms a clade with Coomera Dove & Cribb, 1995 within the Fellodistomidae. The life-cycle of the species is predicted to require two hosts and to involve the direct ingestion of the cercaria.

Galactosomum otepotiense n. sp. (Trematoda: Heterophyidae) infecting four different species of fish-eating birds in New Zealand: genetically identical but morphologically variable

“…is most closely related to species from Australia. This pattern is seen in several species of parasitic helminth (Presswell et al , 2012; Cribb et al , 2014b; Georgieva et al , 2017; Huston et al , 2018), and is perhaps unsurprising when considering that Australia is the closest large land mass and much of New Zealand's marine avifauna has evolved from Australian immigrant species or vice versa (e.g. Diamond, 1984; Given et al , 2005).…”

Bucephalus damriyasai n. sp. (Digenea: Bucephalidae) from the blacktip trevally Caranx heberi (Bennett) (Perciformes: Carangidae) off Bali, Indonesia

“…It is not clear why we have not been successful in securing useful DNA from this species as it was fixed in the same way as other digeneans recovered from the Bali Workshop that have been successfully sequenced (Cribb et al, 2014 ; Bray et al, 2016 ; Yong et al, 2016 ; Bray et al, 2017 ). Successful and experienced molecular biologists in the Rostock and the University of Queensland Laboratories have been frustrated in their attempts to extract DNA from these worms.…”

Digenean parasites of deep-sea teleosts: A progress report

“…The other family studied by Bray et al (1999) was the Fellodistomidae, in particular the relationships of members of the genus Steringophorus Odhner, 1905, finding evidence of deep-sea radiation in the genus. Steringophorus has been resolved as monophyletic, usually in a clade with the deep-sea genus Olssonium Bray & Gibson, 1980 and the cold-water genus Fellodistomum Stafford, 1904, in that and most later studies ( Cribb et al, 2014 ; Sun et al, 2014 ; Wee et al, 2017 ). On the other hand, Pérez-Ponce de León et al (2018) added Steringotrema robertpoulini Pérez-Ponce de León, Anglade & Randhawa, 2018 from a shallow water pleuronectid to the phylogeny, finding it a sister species to S. dorsolineatus ( Reimer, 1985 ) from deep sea ipnopids, which together form a clade sister to the remaining members of Steringophorus .…”