Redescription and genetic characterization of Philometra lagocephali Moravec et Justine 2008 (Nematoda: Philometridae) from Lagocephalus lunaris (Bloch and Schneider) (Tetraodontiformes: Tetradontidae) in the South China Sea

Abstract

Philometra lagocephali Moravec et Justine, 2008 was redescribed using light and scanning electron microscopy based on the new material collected from the lunartail puffer Lagocephalus lunaris (Bloch et Schneider) (Tetraodontiformes: Tetradontidae) in the South China Sea. Our specimens are identical with the original description in the body size of gravid female, the width of cephalic and caudal end, the number and arrangement of cephalic papillae, the relative length of the oesophagus to body length, the size of ventriculus, the morphology of oesophageal bulb and posterior end, and the body size of larvae. In addition, specimens of P. lagocephali were also characterized using molecular methods by sequencing and analysing the small ribosomal DNA (18S rDNA) and mitochondrial cytochrome c coxidase subunit 1 (cox1) target regions. Phylogenetic analyses of genus Philometra base on 18S rDNA sequences was made using Mega 5.2. The results confirmed P. lagocephali is a valid species. It's the first molecular study of this species. These new morphological and molecular data contributed to a more precise and rapid diagnosis of this hitherto poorly known philometrid nematode.

First description of the male of Philometroides acreanensis and phylogenetic assessment of Philometridae (Nematoda: Dracunculoidea) suggest instability of some taxa

“…Philometroides acreanensis was recently described based on two gravid females [6], which is commonly observed in Philometridae [1,18]. Even though the present specimens showed slight differences from those described by [6], mainly regarding the total body length (145-178 vs. 240-280 mm), there is no evidence that they belong to a different species, since they were collected in the same fish and locality as the type host (P. blochii) and locality (River Acre) of P. acreanensis [6].…”

Species ofPhilometra(Nematoda, Philometridae) from fishes off the Mediterranean coast of Africa, with a description ofPhilometra raran. sp. fromHyporthodus haifensisand a molecular analysis ofPhilometra saltatrixfromPomatomus saltatrix

“…Molecular analysis of Philometra species has concerned only a small number of species [4, 28, 33, 34]; sequences of cytochrome c oxidase 1 (COI), typically used for barcoding in other animals [30], were demonstrated to be effective in identifying philometrid species [4, 34]. In our study, we obtained sequences of COI from several Ph.…”