Main Content

The World of Protozoa, Rotifera, Nematoda and Oligochaeta

Ref ID : 6637

Magda de Eguileor, Roberto Valvassori, Giulio Lanzavecchia, and Annalisa Grimaldi; Morphogenesis of helical fibers in haplotaxids. Hydrobiologia 334:207-217, 1996

Reprint

In File

Notes

There are two different muscle fiber types in haplotaxids. The pseudo-circomyarian type is typical of Haplotaxis gordioides and the flattened circomyarian type of Pelodrilus leruthi. The mechanisms of growth in fiber size and in fiber number of the two fiber types in the hindmost region of adult specimens have been studied ultrastructurally. The increase in length and girth of the muscle fiber is always the result of the insertion of new myofilaments in the peripheral zones of the muscle cells. The increase in the number of fibers seems to be due to division of differentiated muscle cells.