Fig. 7.

Ct-syt1 expression in late-stage stage C. teleta larvae (stages 7 – 9). Panels show DIC images of animals after whole mount in situ hybridization for Ct-syt1. Panels d and e are cropped images of the head. All panels are to the same scale unless otherwise noted. Panels l and o are cropped, 2x magnified images of the brain. Panels k and n are cropped, 2x magnified images of the pharynx and correspond to panels j and m, respectively, but are different focal planes. The position of the prototroch (pt) and/or telotroch (tt) are indicated in b – g, i, j and m. The open arrowheads in j and m point to the position of the Ct-syt ⁺ cells in k and n, respectively. Open arrowheads in c, j, k and n indicate Ct-syt1 ⁺ cells near the pharynx. In c, the boundaries of the thoracic and abdominal (abdom.) ganglia are indicated, and an open arrow points to the 9th thoracic ganglion. The brain neuropil (np) is indicated in d, j, l and o. Closed arrowheads in d, e, g and j point to Ct-syt1 ⁺ cells in the head. Open arrows in d and f point to a circumferential row of Ct-syt1 ⁺ cells in the head epidermis, just posterior to the brain. Open arrows in f and g point to longitudinal rows of Ct-syt1 ⁺ cells in the trunk epidermis. The open arrowhead in i points to clusters of Ct-syt1 ⁺ midline cells within the ventral nerve cord. An asterisk marks the approximate position of the mouth. Stage is indicated in the lower-left corner, and view is indicated in the lower-right corner. c and f are reflected right-lateral views. Anterior is to the left in all ventral, dorsal and lateral views, and ventral is down in all anterior views. ant, anterior; dors, dorsal; lat, lateral; pt, prototroch; tt, telotroch; vent, ventral; vlat, ventral-lateral