Pratylenchus penetrans (Cobb, 1917) Filipjev & Schuurmans Stekhoven, 1941 is one of the most well-known members within the genus Pratylenchus Filpjev, 1936. This mobile endoparasite is recorded world-wide but particularly wide spread in the temperate zone of the Northern Hemisphere. It is an important pest of many crops and ornamentals. Morphologically it belongs to a group of close related species, all with 3 lip annuli, a rounded spermatheca, four lateral lines and a rounded smooth tail tip. Males are common in P. penetrans and it reproduces sexually.