Figure 1
Hatched egg and proembryoid I. Lateral view; live specimens immersed in LES (A-C) or in mineral oil (D). In this figure anterior is to the left and the dorsal side is to the top, at least for the anterior half of the animal (see Figure 2 in [27] to better understand orientation). Panels with the same letter indicate different views of the same specimen. (The same conventions apply to all other figures, unless stated otherwise). A: Hatched egg showing what is essentially a final (late stage 8) embryo lying within the cracked chorion (c). B: Hatchling of the same stage with the chorion manually removed. B1 is a high magnification of B, showing in more detail the egg tooth (et) on the second maxillae, which is used to crack the chorion. Note that the embryonic cuticle (ec) on the antennae (a) has already detached from the underlying epithelium (i.e. apolysis has occurred). C-D: proembryoid I, just after moulting in C, with the embryonic cuticle (ec) still attached to the rear of the animal; this exuvia has been manually removed in D. C1: the detached exuvia showing all cuticular traits as laid down in stage 7 embryo. The proembryoid I is still sharply folded at the level of the 17th LBS. The limb buds (lb) appear as lateral protrusions of the ventral segmental units, and are differentially developed along the anteroposterior axis, from the more differentiated antennae (a) to the last formed segment (eventually the last leg-bearing segment), which lacks the limb buds altogether. D1 is a higher magnification of the specimen in D, turned upside down. htb: semicircular dorsal border of the hemitergites; llb: last limb bud; mxp: maxilliped; p: proctodeum; t: tergite. Scale bars: A, B, C, C1, D: 200 μm; B1, D1: 100 μm.