Nematode parasites infecting the starry batfish Halieutaea stellata (Vahl) (Lophiiformes: Ogcocephalidae) from the East and South China Sea

Abstract

The starry batfish Halieutaea stellata (Vahl) is a small, benthic fish found in Indo-West Pacific Oceans. However, our present knowledge of the helminth parasites of this fish is still fragmentary. In this study, a total of 29 fish collected from the East and South China Sea were examined to determine the prevalence, intensity and species composition of helminth parasites in H. stellata. Using morphological and molecular approaches, four species of nematodes were found parasitic in this fish host, including the adults and fourth-stage larvae of Raphidascaroides nipponensis Yamaguti 1941; adults and third-stage larvae of Raphidascaris lophii (Wu 1949), third- and fourth-stage larvae of Hysterothylacium larval type IV-A of Shamsi, Gasser & Beveridge 2013 and third-stage larvae of Hysterothylacium amoyense (Hsü 1993). Halieutaea stellata represents a new host record for the three last-named nematodes. Raphidascaroides nipponensis with the highest prevalence (82.5%) and intensity (mean = 13.5) of infection was considered as the dominant parasite species in H. stellata. The detailed morphology of the different developmental stages of the four nematode species was studied using light and scanning electron microscopy. All nematode species were also genetically characterized by sequencing and analysing the internal transcribed spacer (ITS) of the ribosomal DNA. This study provides further data on the occurrence of nematode parasites in H. stellata and also contributes to facilitate an accurate and rapid diagnosis of the infection by these little-known nematodes.

Morphological and molecular characterization of selected species of Hysterothylacium (Nematoda: Raphidascarididae) from marine fish in Iraqi waters

“…Another Hysterothylacium larval type in the present study was Hysterothylacium type XV, which had been described previously for the first time from the East and South China Sea (Li et al , 2016) and later from the area joining the Persian Gulf and the Gulf of Oman (Shamsi et al , 2016). In the present study, we report three new hosts, P. arsius, S. undosquamis and B. orientalis , for this larval type.…”

Detection of ascaridoid nematode parasites in the important marine food-fish Conger myriaster (Brevoort) (Anguilliformes: Congridae) from the Zhoushan Fishery, China

“…The accurate identification of ascaridoid larvae to the species level is essential for an evaluation of the molecular epidemiology of the disease [ 21 , 22 , 35 ]. Recently, the combination of PCR-RFLP analysis and targeted sequencing of the ITS region has been widely used for large-scale studies on the identification of ascaridoid larvae to the species level [ 11 , 29 , 35 – 40 ].…”

“…Hysterothylacium amoyense (L3) has been reported from several marine fishes, including Scomber japonicus and Trichiurus lepturus in the East China Sea, Halieutaea stellata in the South China Sea [ 21 , 39 ] and Platycephalus indicus (L.) (Scorpaeniformes: Platycephalidae) in the Persian Gulf [ 58 ]. In the present study, the prevalence of H. amoyense (L3) (3.4%) in C. myriaster is distinctly lower than reported in the previous investigation of Halieutaea stellata (24.0%) [ 21 ]. In the case of the third-stage larvae of H. zhoushanense, we found this species in C. myriaster for the first time, with a prevalence of 2.0% and mean intensity of 1.0.…”

“…The morphology of the nematode larvae was observed using light and scanning electron microscopy. For scanning electron microscopy, specimens were prepared according to the methods used in previous studies [ 21 , 22 ]. The following morphological characters were used for the identification of different morphotypes of larval nematodes as in previous studies [ 22 – 27 ], including the position of the excretory pore, the absence and presence of an intestinal caecum and a ventricular appendix and their relative lengths, and the morphology of the ventriculus and tail tip.…”

Some adult and larval nematodes from fishes off New Caledonia

“…In addition, there were a number of other sequences in GenBank (Table 2) which were highly similar to sequences of the Raphidascaris specimens in the present study. Of the sequences listed in Table 2, and Li et al (2016) provided both morphological description and sequence data for R.…”