Host and ecology both play a role in shaping distribution of digenean parasites of New Zealand whelks (Gastropoda: Buccinidae: Cominella)

Abstract

Digenean parasites infecting four Cominella whelk species (C. glandiformis, C. adspersa, C. maculosa and C. virgata), which inhabit New Zealand's intertidal zone, were analysed using molecular techniques. Mitochondrial 16S and cytochrome oxidase 1 (COI) and nuclear rDNA ITS1 sequences were used to infer phylogenetic relationships amongst digenea. Host species were parasitized by a diverse range of digenea (Platyhelminthes, Trematoda), representing seven families: Echinostomatidae, Opecoelidae, Microphallidae, Strigeidae and three, as yet, undetermined families A, B and C. Each parasite family infected between one and three host whelk species, and infection levels were typically low (average infection rates ranged from 1·4 to 3·6%). Host specificity ranged from highly species-specific amongst the echinostomes, which were only ever observed infecting C. glandiformis, to the more generalist opecoelids and strigeids, which were capable of infecting three out of four of the Cominella species analysed. Digeneans displayed a highly variable geographic range; for example, echinostomes had a large geographic range stretching the length of New Zealand, from Northland to Otago, whereas Family B parasites were restricted to fairly small areas of the North Island. Our results add to a growing body of research identifying wide ranges in both host specificity and geographic range amongst intertidal, multi-host parasite systems.

Annotated checklist and genetic data for parasitic helminths infecting New Zealand marine invertebrates

“…16S, KU525065–KU525076 (Donald & Spencer, 2016), FJ396104–FJ396125, FJ396129, FJ396134 (Leung, Keeney, & Poulin, 2009); ITS1 , KU695771–KU695783 (Donald & Spencer, 2016), FJ396158–FJ396161 (Leung, Keeney, & Poulin, 2009)…”

“…References . Allison (1979); Babirat et al (2004); Donald and Spencer (2016); Leung, Donald, et al (2009); Leung, Keeney, and Poulin (2009); Lloyd and Poulin (2011); McFarland et al (2003); Mouritsen et al (2003); Poulin and Mouritsen (2004, 2006); Thieltges et al (2009).…”

“…The objective of this study is to provide the first comprehensive checklist of parasitic helminths (acanthocephalans, cestodes, nematodes, and trematodes) currently known to infect New Zealand marine invertebrates. We focused on New Zealand marine invertebrates because the coast has been the focus of various parasitological surveys in the past two decades (e.g., Donald & Spencer, 2016; Koehler & Poulin, 2010; Leung, Donald, et al, 2009) but never have all published data been brought together in a succinct form. We also include new records of infections from a recent and extensive parasite biodiversity survey undertaken between June 2019 and August 2021 from the Otago Coast, South Island.…”

Morphological and molecular assessment of the diversity of trematode communities in freshwater gastropods and bivalves in Los Tuxtlas tropical rainforest

“…Scholz et al ., 2001; Gilardoni et al ., 2011; Veeravechsukij et al ., 2018). The modern approach to describe larval trematode diversity has been successfully used by several authors (see Kudlai et al ., 2015; O'Dwyer et al ., 2015; Donald & Spencer, 2016; Chontananarth et al ., 2017; Gordy & Hanington, 2018; Huston et al ., 2018; Cribb et al ., 2019; Onaca et al ., 2020). We followed such approach and were able to allocate the 12 cercarial morphotypes into 16 putative species, using a combination of morphological and molecular data along with other sources of information such as the previous records of trematodes in the surrounding area, host association and geographical distribution.…”

“…The procedure to achieve the identification of cercariae followed that used previously by several authors (Kudlai et al ., 2015; O'Dwyer et al ., 2015; Donald & Spencer, 2016; Chontananarth et al ., 2017; Gordy & Hanington, 2018; Huston et al ., 2018; Cribb et al ., 2019; Onaca et al ., 2020). DNA sequences were generated for individuals representing cercarial morphotypes (and sometimes their intra-molluscan stages), and first screened through the BLAST tool available in GenBank to check that only parasite DNA was amplified, and to preliminary assign each morphotype to a superfamily or family-level group; in some cases, a link was established and morphotypes were assigned to genus and even to species levels.…”