Figure 2

A Hatching larvae with everted introvert. Anterior up. Arrows point to folds caused by movement of the larvae. Dot denotes posterior tubulus. B Same larva as in A rotated by 90°. Anterior up. Dots and arrows as in A. C Another hatching larva. Anterior up. Three tubuli are visible (dots). Bracket indicates the introvert. Arrow as in A D Anterior view of larva shown in A and B. Seven first-ring scalids and one smaller second-ring scalid (asterisk). E Anterior view of another larva. F Larva with fully retracted introvert. Anterior up. Dot as in A. G Magnification of the cuticle surface of the mouth field (mf). Arrows point at small pores. H Anterior part of a hatching larva with protruded introvert. Anterior up. Introvert (I), neck (N) and trunk (T) are clearly distinguishable. I Magnification of the larva shown in H. Abbreviations: 1–7, first-ring scalids one to seven; dor/ven, dorsal or ventral; I, introvert; lat, lateral; mf, mouth field; N, neck; T, trunk.