Lymphocystivirus cause mass mortality events like megalocytiviruses and ranaviruses, fish with lymphocystis exhibit grossly visible papilloma-like skin lesions which substantially reduce their commercial value. No vaccines are currently available for lymphocystis viruses. Group: dsDNA The genus "Lymphocystivirus" has only one species: "Lymphocystis disease virus 1" (LCDV-1), but Lymphocystis disease virus 2 (LCD-2) is another virus that has been proposed as a second member. LCDV-1 infects European flounder "Platichthys flesus" and European plaice ("Pleuronectes platessa"). LCDV-2 infects the common dab ("Limanda limanda"). A third species Lymphocystis disease virus C has also been proposed based on the relative lack of sequence similarity of
Flatfish around "ponds" of sulphur at hydrothermal vents on the seafloor. No other flatfish is known from hydrothermal vents. Many species will enter brackish or fresh water, and a smaller number of soles (families Achiridae and Soleidae) and tonguefish (Cynoglossidae) are entirely restricted to fresh water. The most obvious characteristic of the flatfish is its asymmetry, with both eyes lying on the same side of the head in the adult fish. In some families, the eyes are usually on the right side of the body (dextral or right-eyed flatfish), and in others, they are usually on the left (sinistral or left-eyed