Stage 37
This is the Early Juvenile I Stage (CirobuD:0000060), which occurs when the endostyle axis is almost parallel to the axis passing through the stalk (63-72 h (3 dpf), Stage 37). The stomach swells and the larval tail remnants are no longer present 4 dpf.
The hermaphrodite reproductive system (CirobuA:0000909) is now recognizable. The female reproductive system (CirobuA:0000910) is formed by a sac-like ovary (CirobuA:0000672) continuous in an oviduct (CirobuA:0000801). The male reproductive system (CirobuA:0000910) comprises the lobular testis encrusting the ovary (CirobuA:0000742) and the sperm duct (CirobuA:0000920). Germ cells (CirobuA:0000916) are maturing within the gonads.
The stalk base forms test villi (CirobuA:0000927), each one furnished with a test vessel (CirobuA:0000928) in continuity with the haemocele. They ensure firm adhesion to the substrate. In the body, several blood sinuses (CirobuA:0000856) can be recognized among organs.
After Stage 37, other territories become histologically recognizable (data not shown). These are the cloacal cavity (CirobuA:0000852), the dorsal languets (CirobuA:0000636) on the roof of the branchial chamber (CirobuA:0000863), the pharyngo-epicardial openings (CirobuA:0000868) putting the epicardiac cavities (CirobuA:0000879) in communication with the branchial one, the endostylar appendix (CirobuA:0000866), the oral pigment spots (CirobuA:0000899) and the atrial pigment spots (CirobuA:0000854) encircling the oral and the cloacal siphon border, respectively.
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