Larval anisakid nematodes in teleost fishes from Lizard Island, northern Great Barrier Reef, Australia

Abstract

A survey was undertaken to characterise larval anisakid nematodes present in teleosts at Lizard Island on the northern Great Barrier Reef. In total, 464 fish were examined from 32 families, 62 genera and 107 species. Anisakid nematodes were found in 46 (9.9%) of the fish examined. Infections in Atherinidae, Lethrinidae, Lutjanidae and Serranidae were moderately prevalent, with the intensities of infection ranging from 1 to 80; whereas in the Sphyraenidae and Scombridae, the prevalence of infection was very high, with intensities ranging from 1 to .375 anisakids. A combined morphological and molecular-phylogenetic approach was employed to identify larval anisakid nematodes to species and/ or genotypes. The nematodes examined were identified as Anisakis typica (three genotypes based on molecular characterisation), Terranova Types I (five genotypes) and II (five genotypes) and Hysterothylacium Types IV, V (four genotypes), VI and X. The findings of the present study provide some insights into the distribution of larval anisakid nematodes in coral-reef fishes and a basis for future investigations of anisakid populations in marine fishes.Additional keywords: Anisakidae, first and second internal transcribed spacers (ITS-1 and ITS-2) of nuclear ribosomal DNA, Nematoda, single-strand conformation polymorphism (SSCP) analysis.

Morphological and Molecular Characteristics of Anisakis typica Larvae in Two Species of Threadfin Bream, Nemipterus hexodon and N. japonicus, from the Gulf of Thailand

“…Based on morphological characteristics observed using both light and scanning electron microscopy, L3 anisakid larvae in the present study were morphologically similar to previous specimens studied [19,22,[26][27][28][29][30]. For example, a distinct boring tooth and undeveloped lips at the anterior end of larva, the position of the excretory pore at the base of ventrolateral lips below the boring tooth and the rounded tail with a mucron were similar to those previously described [31].…”

Anisakis (Nematoda: Ascaridoidea) from Indonesia

“…The larvae have been found in scombrids and carangids such as Auxis thazard thazard and Thunnus thynnus from Brazil (SW Atlantic); Scomber japonicus and Trachurus picturatus from the NE Atlantic off Madeira; Euthynnus affinis, Scomberomorus commerson, Sarda orientalis and C. hippurus from the west Indian Ocean off Somalia; and from Merluccius merluccius from the eastern Mediterranean Sea . Further records were provided by Mattiucci et al (2005) from Florida, Farjallah et al (2008) from the Mediterranean coast of North Africa (Scomber scombrus, M. merluccius, Phycis phycis), from Australia by Cannon (1977) and more recently by Shamsi (2007Shamsi ( , 2014 and Jabbar et al (2012) from the Great Barrier Reef, and by Chen & Shih (2015) from Taiwan. Kuhn et al (2013) have already summarized the worldwide known hosts for genetically confirmed worms, naming 26 different teleost species.…”

Foodborne anisakiasis and allergy

“…Critical for the identification of worms to the species level is the use of reliable genetic markers. The first and second internal transcribed spacers (ITS-1 and ITS-2, respectively) of nuclear ribosomal DNA have proven useful for the specific or genotypic identification of many anisakids [31,32]. The sequence differences between or among species is usually much higher than variation within species [33].…”

“…Six years later, the first clinical case of anisakiasis was reported in China [50]. Recent studies from Australasia also demonstrated prevalences of up to 100% for species including Neoplatycephalus richardson (tiger flathead) and Sillago flindersi (eastern school whiting) from temperate waters, and Scomberomorus commerson (narrow-barred Spanish mackerel) and Sphyraena forsteri (Bigeye barracuda) from tropical waters [27,31,35,36,51].…”