Expression of larvacean Pax2/5/8 paralogs at pre-tailshift stage, when organogenesis nears completion. (A) Pax2/5/8a. (B) Pax2/5/8b. (C) Schematic representation summarizing the non-overlapping Pax2/5/8a (red) and Pax2/5/8b (blue) expression domains. Arrows indicate perforations where epidermal fusions occur and Pax2/5/8 paralogs are expressed. Abbreviations: a, anus; ab, anterior brain; cr, ciliary ring; en, endostyle; es, esophagus; h, heart; lr, Langerhans receptor; m, mouth; ph, pharynx; r, rectum; s, stomach. Scale bar = 10 μm.