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
Assessor flavissimus in crevices,often swimming upside down. The males mouthbrood, guarding the eggs in their mouths. Assessor flavissimus Assessor flavissimus, the yellow devilfish or yellow scissortail, is a fish from the western Central Pacific, recorded from the Great Barrier Reef]] and Papua New Guinea. It occasionally makes its way into the aquarium trade. It grows to a size of 5.5 cm in length. It is bright yellow in colour and has a reddish-orange stripe running from the eye to the upper edge of the operculum, and a reddish-orange band on the dorsal and anal fins which is parallel to the fin margin.