Figure 8

Armorloricus elegans. Light micrography of a Higgins larva stage (A). Body musculature visualized by fluorescently-labeled phalloidin staining and CLSM (B and C) and by 3D imaging (D and E). Anterior faces upwards in all aspects. A: Dorsal view. Specimen with fully retracted mouth cone (indicated by the dashed line). Note the posterior toes with cut-off mucrones. B: Ventral view. The myoanatomy is more complex in the anterior half of the body. Note that the posterior toes lack muscles inside. C: Close up of the mouth cone musculature. Dorsal view. D: Dorsal view. E: Ventral view. Color code: anal sphincter, pink; anterior ring muscle, dark blue; anterodorsal longitudinal retractor muscles, green; anterodorsal semicircular muscle, dark orange; anteroventral short longitudinal muscles, light purple; dorsal double transverse muscle, purple; lateral short transverse muscle, dark red; mouth cone musculature (including pharyngeal bulb and mouth cone longitudinal muscles), white; posterior short longitudinal muscles, light green; posteriormost short longitudinal muscles, yellow; posterodorsal longitudinal retractor muscles, blue; short midventral longitudinal muscles, dark green; thin longitudinal muscles, dark yellow; thin middorsal transverse muscle, light blue; thin posteroventral transverse muscle, brown; triangular posteroventral muscle, grey; ventral double transverse muscle, orange; ventral longitudinal retractor muscles, red. Abbreviations: *, mouth cone musculature; a, abdomen; ad, anterodorsal longitudinal retractor muscles; ads, anterodorsal semicircular muscle; avs, anteroventral short longitudinal muscles; as, anal sphincter; cs, clavoscalid; ddt, dorsal double transverse muscle; i, introvert; lo, lorica; lst, lateral short transverse muscle; mcr, mouth cone longitudinal retractors; muc, mucrones; pbm, pharyngeal bulb musculature; pms, posteriormost short longitudinal muscles; ps, posterior short longitudinal muscles; pd, posterodorsal longitudinal retractor muscles; se, posterolateral sensory setae; ss, spinoscalids; svl, short midventral longitudinal muscles; t, thorax; tb, thin longitudinal muscles of the base of the mouth cone; tdt, thin middorsal transverse muscle; thp, thoracic plates; tl, thin longitudinal muscles; tv, triangular posteroventral muscle; vl, ventral longitudinal retractor muscles; arrows, posterior toes; arrowheads, anterior ring muscle; double arrows, thin longitudinal muscles; double arrowheads, ventral double transverse muscle; open arrowheads, thin posteroventral transverse muscle.