6533b831fe1ef96bd12983b9

RESEARCH PRODUCT

Ultrastructure, development, and moulting of the aesthetascs of Neomysis integer and Idotea baltica (Crustacea, Malacostraca)

subject

description

The development of the aesthetascs of Neomysis integer (Malacostraca, Mysidacea) and Idotea baltica (Malacostraca, Isopoda) were investigated by electron microscope methods. Basically the aesthetascs of both species develop according to the same pattern. The newly formed sensillar shafts lie invaginated within the epidermal tissue. They are formed by numerous enveloping cells, which are arranged telescopically one by one. Each enveloping cell secretes a definite portion of the new shaft cuticle. The innermost enveloping cell extends furthest distally and deposits the cuticle of the future shaft tip. The outer enveloping cells produce the cuticle of the more proximal shaft portions. Whereas the morphogenesis of the aesthetascs of both species is uniform, the moulting processes are different. In the aesthetascs of Neomysis the morphological basis for a continuation of the sensitivity remains until ecdysis, as an intact dendritic connection between the sensory cells and the old shaft is maintained. In Idotea, the aesthetascs cease to function during the early moulting stages.