The family Paratylenchidae Thorne, 1949 in the rhizosphere of grass and woody species in Europe: a review of the literature

The family Paratylenchidae (Paratylenchus, Gracilacus) belonging to the suborder Criconematina Siddiqi, 1980 including several others families: Criconematidae Taylor, 1936, Hemicycliophoridae Skarbilovich, 1959, Shaeronematidae Raski & Sher, 1952 and Tylenchulidae Skarbilovich, 1947. Members of these families are parasites of higher plants with a higher abundance in perennial cultural plants. Generally we can consider members of the suborder Criconematina as numerous, adaptable, more or less specialized plant parasitic nematodes occurring worldwide. The main common features of specimens of this suborder are relatively long and robust stylet and small body size. This combination enabled them to inhabit also very poor sites in considerable numbers where other nematodes have no chance. A stylet of Paratylenchus nematodes is from 10 to 40 μm of length, the Gracilacus nematodes from 40 to 120 μm of length. The nematodes of the genus Paratylenchus with shorter stylet attack and damaged the cuticular cells of host roots, however, the nematodes of the genus Gracilacus with the longer stylet are able to damage a deeper level of plant roots. Presented review should serve as a list and an outline of what was by some members of the genera Paratylenchus and Gracilacus previously published in connection with trees and grassland.