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
Hypselodoris kanga white. The inner edge of each gill is reddish orange in the upper quarter, deep blue in the mid region and white in the basal quarter. The smooth outer side of each gill is orange-red in the upper quarter and the rest has a background colour of light blue with a row of large yellow spots. The two outer corners of each gill are bordered with red at the tip becoming dark blue at the base. This species can reach a total length of at least 70 mm and has been observed feeding on yellow sponges from the genus "Dysidea".