World distribution and possible geographic origin of palm lethal yellowing disease and its vectors

The literature on the former and current world distribution of palm lethal yellowing disease of coconut and other palms, which is apparently caused by mycoplasma-like organisms, is reviewed. The distribution records for some localities and periods are incomplete, and conclusions based on the early literature are tentative, but the disease appears to have been known in the Caribbean region for at least 100 years and in West Africa for at least 50 years. During the last decade, an epiphytotic of the disease occurred in south-eastern Florida and the disease has recently been found in Texas and Mexico. However, it seems to have disappeared from some formerly affected areas. The relationships between the disease in Africa and the Americas, the known geographical distribution of Myndus crudus Van D., which is thought to be a vector, and 2 hypotheses concerning the origin of the disease and its vectors are discussed.