The types of supplements in the family Tobrilidae (Nematoda, Enoplia)

摘要

The structure of supplementary organs and buccal cavity are the main diagnostic features for identification of Tobrilidae species. Four main supplement types can be distinguished among representatives of this family. Type I supplements are typical for Tobrilus, Lamuania and Semitobrilus and are characterised by their small size and slightly protruding external part. There are two variations of the type I supplement structure: amabilis and gracilis. Type II is typical for several Eutobrilus species (E. peregrinator, E. prodigiosus, E. strenuus, E. nothus). These supplements are very similar to the type I supplements but are characterised in having a highly protruding torus with numerous microthorns and a bulbulus situated at the base of the ampoule. Type III is typical for Eutobrilus species from the Tobrilini tribe, i.e., E. graciliformes, E. papilicaudatus and E. dffertus, and Mesotobrilus spp. from the Paratrilobini tribe and is characterised by a well-defined cap and a bulbulus situated at the base of the ampoule. Type IV is observed in the majority of Eutobrilus, Paratrilobus, Brevitobrilus and Neotobrilus and is the most complex supplement type with a mobile cap and an apical bulbulus. The origin of nematode supplementary organs from unspecialised setae can be illustrated by the evolution of tobrilid supplements.