Fig. 5

A. mollis pentactula (early juvenile). a Pentactula (27-day) stained with Nile Red under blue light excitation. Note minimal external lipid staining. Granular mass (GM), hyaline spheres (HS), oral tentacles (OT, circled). Scale bar: 75 µm. b Confocal image of pentactula (27-day) stained with Hoechst nuclear dye, LipidTOX™ green neutral lipid stain and LipidTOX™ red phospholipid stain showing formation of juvenile digestive system (DS) and oral tentacles (OT, circled). Scale bar: 50 µm. c Section through pentactula (27-day) with degrading hyaline spheres (HS) and multiple lipid transporting cells (LTC, white circle) between blastocoelic fibres (F). Oral tentacles (T) and water vascular system (WVS). Scale bar: 50 µm. d Pentactula (27-day) with degrading hyaline spheres (HS), developing juvenile digestive system (DS) and lipid transporting cells (LTC, white circle) in blastocoel (Bl) and within the HS. Scale bar: 35 µm. e Pentactula (27-day) longitudinal section showing hyaline spheres (HS) close to developing juvenile digestive system (DS). Oral tentacles (T), fibrillar matrix (F) and granular mass (GM). Scale bar: 80 μm. f Pentactula (27-day) longitudinal section showing hyaline spheres (HS) close to developing juvenile digestive system (DS). Oral tentacles (T), granular mass (GM). Scale bar: 120 μm