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CNE_22355_sm_suppfig1.tif32199KSupplementary Fig. 1(A-B): Structure of the early larval brain of Cupiennius salei. Light micrographs of parasagittal sections through the brain of a larva (1st larval stage) stained with Toluidine. (A) Medial sections, (B) lateral section. See text and figure legend 2 for further details. ABco, arcuate body cortex; chn, cheliceral neuromere; l1n, neuromere associated with the segment of walking leg 1; MBco, mushroom body cortex; MBnp, mushroom body neuropile; MBco GBp, mushroom body cortex, globuli precursors; ms, muscles; oe, oesophagus; OCco, optic centre cortex; OCmnp, median optic centre neuropile; OClnp, lateral optic centre neuropile; pedn, pedipalpal neuromere; PME, posterior median eye. PRCco, protocerebral cortex; PRCnp, protocerebral neuropile; PRCpg, protocerebral precursor groups; VNCnp, ventral nerve cord neuropile. Scale bar: (A) 150 μm in panel A,B.
CNE_22355_sm_suppfig2-3.tif19628KSupplementary Fig. 2: Neural precursor groups arise in the surface of the PLE/ALE groove (see also supplementary movie 1). Confocal micrograph of a maximum projection of optical horizontal sections from 28 to 62 μm; anterior is towards the top, medial towards the left. The arrows point to neural precursor groups in the groove. Supplementary Figure 3 A-B: dachshund and Prospero are co-expressed in the developing mushroom bodies. Merged confocal and light micrographs of embryos stained with a DIG-labelled dac RNA probe (dark green) and the Cupiennius salei anti-Prospero antibody (magenta). (A) The arrow points to Prospero positive cells in the ring-shaped dac domain that corresponds to the mushroom body vesicle in the anterior area of the developing protocerebrum. At 180 hours only few cells co-express Prospero and Csdac in the ring-shaped structure of the developing mushroom body. (B) The arrow points to the additional dac domain posterior to the ring-shaped domain. Many cells in this posterior domain express Prospero. Additonal cells co-express Prospero and Csdac in the ring-shaped structure (arrowheads). MB, developing mushroom body.

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