A new species of Ascarophis (Nematoda, Cystidicolidae) from the stomach of the marine scorpaeniform fish Hoplichthys citrinus from a seamount off the Chesterfield Islands, New Caledonia

Abstract

A new species of parasitic nematode, Ascarophis (Similascarophis) richeri sp. nov. (Cystidicolidae), is described from the stomach of the marine scorpaeniform fish Hoplichthys citrinus Gilbert (Hoplichthyidae) (prevalence 19%, intensity 1-8 nematodes per fish) collected in the region of the Chesterfield Islands (Coral Sea, west of New Caledonia) in October 2005. The new species, studied using both light and scanning electron microscopy, is characterized mainly by the structure of the mouth (highly reduced pseudolabia, high pseudolabial terminal projections, no submedian labia, well-developed, bilobed sublabia), bifurcate deirids, the length of the spicules (663-729 µm and 105-108 µm) and the presence of filaments on both egg poles (2-5 on each). Similascarophis MuZoz, González et George-Nascimento, 2004 is considered a subgenus of Ascarophis van Beneden, 1871 to accommodate the species characterized by highly reduced pseudolabia. Presence of the new species in fish from Seamount Nova (Lord Howe Rise) but not from the Chesterfield plateau suggests that it is endemic to this seamount, a case already encountered for many benthic invertebrates. RésuméUne nouvelle espPce de Nématode parasite, Ascarophis (Similascarophis) richeri sp. nov. (Cystidicolidae), est décrite de l'estomac du poisson marin Hoplichthys citrinus Gilbert (Scorpaeniformes, Hoplichthyidae) (prévalence 19%, intensité 1-8 nématodes par poisson) collecté en octobre 2005 dans la région des Îles Chesterfield (Mer du Corail, Ouest de la NouvelleCalédonie). La nouvelle espPce, étudiée au microscope photonique et au microscope électronique B balayage, est caractérisée principalement par la structure de la bouche (pseudolabia trPs réduites, terminaison des pseudolabia haute, pas de labia submédiane, sublabia bien développées et bilobées), des deirides bifurquées, la longueur des spicules (663-729 µm et 105-108 µm) et la présence de 2-5 filaments sur chaque pôle des Éufs. Similascarophis MuZoz, González et George-Nascimento, 2004 est considéré comme un sous-genre de Ascarophis van Beneden, 1871, et inclut les espPces caractérisées par des pseudolabia trPs réduites. La présence de la nouvelle espPce dans des poissons provenant du mont sous-marin Nova (Ride de Lord Howe) mais pas du plateau des Chesterfield suggPre qu'elle est endémique B ce mont, un cas déjB rencontré chez de nombreux invertébrés benthiques.

Two cystidicolids (Nematoda, Cystidicolidae) from marine fishes off New Caledonia

“…Moreover, the shape of A. adioryx pseudolabia in apical view is more similar to that in Pseudascarophis Ko, Margolis et Machida, 1985 than in most Ascarophis spp. (Ko et al 1985), but the shape and size of pseudolabia may somewhat differ in different species of the latter genus (Moravec and Justine 2007).…”

“…nov. is proposed to accommodate it. Moravec and Justine (2007) consider Similascarophis Muñoz, González et George-Nascimento, 2004 a subgenus of Ascarophis. However, it is necessary to remark that the cephalic structures of the majority of Ascarophis spp.…”

Two new species of cystidicolid nematodes from the digestive tract of the deep-sea fish Coryphaenoides mediterraneus (Giglioli) (Macrouridae) from the Mid-Atlantic Ridge

“…In this list, Mastigospirura Machida & Syahailatua, 1994 was omitted (Machida & Syahailatua, 1994). More recently, Sterliadochona was designated a genus inquirendum, a new genus, Salmonema Moravec, Santos & BrasilSato, 2008, was established (Moravec et al, 2008, and Similascarophis has been considered a subgenus of Ascarophis by Moravec (2007) and Moravec & Justine (2007). The latter authors have stated that it is apparent from SEM studies that the shape and size of pseudolabia may differ somewhat in different Ascarophis spp.…”

“…Ferrer et al (2005) listed 33 species of Ascarophis considered valid. A few additional congeneric species have recently been reported by Moravec & Justine (2007), Muñoz & George-Nascimento (2007) and Brugni & Viozzi (2008). Of these, only 11 species possess non-filamented eggs, but only three of these have a left spicule similar in length to that in the new species, i.e.…”

Neolebouria blatta n. sp. (Digenea: Opecoelidae) from Pristipomoides argyrogrammicus (Valenciennes) and Etelis carbunculus Cuvier (Perciformes: Lutjanidae) off New Caledonia

“…Only a few isopods (Trilles & Justine, 2004, nematodes (Petter & Le Bel, 1992;Moravec & Justine, 2007), cestodes (Beveridge & Justine, 2006Kuchta, et al, 2009) and monogeneans (Justine, 2008a(Justine, , b, 2009 have been reported from deep water off New Caledonia. In this paper we describe a common and abundant new opecoelid species in a deep water lutjanid, the ornate jobfish Pristipomoides argyrogrammicus (Valenciennes).…”