An update and ecological perspective on certain sentinel helminth endoparasites within the Mediterranean Sea

Abstract

The Mediterranean Sea is recognized as a marine biodiversity hotspot. This enclosed basin is facing several anthropogenic-driven threats, such as seawater warming, pollution, overfishing, bycatch, intense maritime transport and invasion by alien species. The present review focuses on the diversity and ecology of specific marine trophically transmitted helminth endoparasites (TTHs) of the Mediterranean ecosystems, aiming to elucidate their potential effectiveness as ‘sentinels’ of anthropogenic disturbances in the marine environment. The chosen TTHs comprise cestodes and nematodes sharing complex life cycles, involving organisms from coastal and marine mid/upper-trophic levels as definitive hosts. Anthropogenic disturbances directly impacting the free-living stages of the parasites and their host population demographies can significantly alter the distribution, infection levels and intraspecific genetic variability of these TTHs. Estimating these parameters in TTHs can provide valuable information to assess the stability of marine trophic food webs. Changes in the distribution of particular TTHs species can also serve as indicators of sea temperature variations in the Mediterranean Sea, as well as the bioaccumulation of pollutants. The contribution of the chosen TTHs to monitor anthropogenic-driven changes in the Mediterranean Sea, using their measurable attributes at both spatial and temporal scales, is proposed.

Parasitological transitions: selected outcomes from the XXXII Congress of the Italian Society for Parasitology

“…Specific examples are provided in the review by Palomba et al . ( 2023 ) of this SI, which developed the discussion held during the Symposium.…”

Re‐evaluation of certain aspects of the EFSA Scientific Opinion of April 2010 on risk assessment of parasites in fishery products, based on new scientific data. Part 1: ToRs1–3

“…In recent years, the occurrence of larval cestodes ( Trypanorhyncha ) of the genera Molicola and Gymnorhynchus has been reported in the edible parts (muscle) of fish of commercial importance (i.e. scabbard fish, Lepidopus caudatus ) (Palomba, Marchiori, et al., 2023 ). These larval parasites are maturing to the adult stage in elasmobranchs in European waters.…”

“…As for anisakid nematodes, successful transmission requires a wide availability of suitable definitive and intermediate hosts, with a sufficient population size, and stable marine trophic chains that allow the parasites to complete their life cycle. When conditions are favourable, a large parasite population can be maintained in fishing grounds (for a review see Mattiucci et al., 2018 ; Palomba, Marchiori, et al., 2023 ).…”

“…For example, A. typica sp. A has shown increased prevalence values in the eastern Mediterranean basin and in the Central Mediterranean (off the Malta coast) in co‐infection with A. pegreffii and A. physeteris (Palomba, Marchiori, et al., 2023 ). Previous molecular epidemiological studies had failed to detect this parasite in these locations (Mattiucci et al., 2018 ).…”

“…Previous molecular epidemiological studies had failed to detect this parasite in these locations (Mattiucci et al., 2018 ). Considering the pelagic/mesopelagic life cycle of this parasite species and its capacity to infect fish muscle, we cannot exclude the possibility of the higher probability of infection in fish in Mediterranean waters in the future and the possibility of accidental transmission to farmed fish species in southern European countries (Palomba, Marchiori, et al., 2023 ).…”