Lepeophtheirus pectoralis copepodid stage, during which the copepod attaches itself to the fish. Stages IV, V, VI and VII are the chalimus stages, and are followed by the pre-adult and adult stages, when differentiation of males and females is possible. Lepeophtheirus pectoralis Lepeophtheirus pectoralis is a species of parasitic copepod. It is a parasite of flatfish, the most frequent hosts being the European flounder ("Platichthys flesus"), the plaice ("Pleuronectes platessa"), and the dab ("Limanda limanda"). It feeds on the mucus, skin and blood of the fish, with oviferous females being found in the pectoral and pelvic fins of the host, while immature
Pseudorhombus arsius Pseudorhombus arsius Pseudorhombus arsius, the largetooth flounder, is a species of left-eyed flatfish, that is the dark side with the eyes on the adult fish is the left side of the fish's body, from the family Paralichthyidae. As "Rhombus polyspilos" it was named as the type species of the genus "Pseudorhombus". It is an Indo-Pacific species and is fished for by both recreational and commercial fisheries. "Pseudorhombus arsius" has an oval-shaped body which has a depth which is 1.8 to 2.3 times its standard length. The head has a slight notch in front of upper eye. The eyes are on