[6] P. hamatus inhabits soils in both Europe and North America, and was originally isolated from fig in central California in 1950.

[4] P. hamatus has also been documented to cause patchy areas of chlorosis and wilting in lentils, resulting in up to 40% yield loss.

[2] Symptoms appear in patches or clusters and plants show a slow and general decline in growth and vigor.

If the symptoms of wilting and chlorosis present in scattered groups or clusters, then the soil and root samples should be screened for P.

Paratylenchus hamatus is a migratory endoparasite which means it retains its vermiform shape during its adult life.

[11][3] Young, easily penetrated root tips appear to be the main food source for juveniles, which have smaller stylets compared to their adult counterparts.

[3] They are primarily located in North America and Europe in cooler environments with adequate moisture since they cannot move without the presence of water films in the soil.

[1] However, these nematodes can persist in very adverse soil environmental conditions (decreases in nutrients, low moisture contents and temperature) in the J4 or pre-adult stage.

have been shown to cause more damage in host root tissue when temperatures are around 20 °C and they prefer levels of pH around 6.5 for optimal reproduction.

However, data from stone fruit farms in California show no damage to crops with populations of pin nematodes reaching 3000 nematodes/ 1 kg of soil.

For example, P. hamatus in mint caused losses of 25% - 36% when planted in soil with 8000 nematodes/ quart, which shows it does not play an antagonistic role.

[10] Overall, the disease severity of P. hamatus is variable and is specific to the species of plant that it is parasitizing on and the concentration at which it is found.