Comparison of the oesophageal structure in Aphelenchoides and Hoplolaimus (Tylenchida: Nematoda)

Within the order Tylenchida the number of oesophageal cells could be expected to be constant; comparison of published information on Aphelenchoides and Hoplolaimus suggests there are similar sets of cells. In Aphelenchoides the first set of radial cells is very elongated (from head framework to metacorpus) and subsequent radial cells are all compressed in the metacorpus. In Hoplolaimus the sets of radial cells are more regular in length, but the first set (six stylet protractor muscles) shows a similar, complicated structure. These similarities confirm that the Aphelenchina represent a suborder of the Tylenchida.