Fig. 3
Muscles that move the dactylus. a Fluorescence micrograph of a pereopod of Porcellio scaber, showing the flexor (Fle) and extensor (Ext) muscles of the dactylus. Each muscle attaches to a long apophysis (arrows). b Apophyses (yellow), shown in a 3D reconstruction of the propodus-dactylus joint. The apophysis of the flexor (Afle) attaches ventrally in the medial region and the apophysis of the extensor (Aext) dorsally in the anterior region of the dactylus. c Optical section through the medial region of the joint, showing the apophysis of the flexor (arrow). The dorsal margin of the joint is to the upper right of the image. d Optical section through the anterior region of the joint, showing the apophysis of the extensor (arrow). Scale bars: 100 μm (a), 50 μm (b, c, d)