Hesiolicium gen.n. (Turbellaria Acoela) and Observations on Its Ultrastructure

Crezée, M. (University of Florida Marine Laboratory, Gainesville, FL 32611, USA) and Tyler, S. Hesiolicium gen.n. (Turbellaria Acoela) and observations on its ultrastructure. Zool. Scr. 5 (5): 207–216, 1976. —Hesiolicium inops gen.n., sp.n. is a thin and elongate protandric hermaphrodite from the marine interstitial environment. The male pore, with no accessory organs, lies just posterior to the mouth, with no pharynx. The dorsal ovary, lateral testes, adhesive papillae and a caudal organ are other features. The posterior and midventral adhesive papillae are bundles of haptocilia up to 22 μm long. In a crook near their base these adhesive cilia have three microtubule doublets displaced from the rest of the axoneme, giving the crook region a figure‐eight cross section. The caudal organ is a complex of cilium‐bearing sensory cells, large gland cells and modified muscle and epidermal cells. The rootlets of epidermal cilia and the two axial units of the sperm are as described for other acoels. Principally because of the haptocilia, Hesiolicium is provisionally placed in the Paratomellidae.

[1]  M. Crezée Monograph of the solenofilomorphidae (Turbellaria: Acoela) , 1975 .

[2]  E. Ruppert,et al.  On the Fine Structure of Gastrotrichs with Description of Chordodasys antennatus sp.n. 1 , 1974 .

[3]  S. Ito Form and function of the glycocalyx on free cell surfaces. , 1974, Philosophical transactions of the Royal Society of London. Series B, Biological sciences.

[4]  E. Ferrero A Fine Structural Analysis of the Statocyst in Turbellaria Acoela , 1973 .

[5]  S. Tyler An Adhesive Function for Modified Cilia in an Interstitial Turbellarian , 1973 .

[6]  E. Ferrero,et al.  The ultrastructure of ciliary sensory cells in two Turbellaria Acoela. , 1973, Tissue & cell.

[7]  A. Nelson-Smith,et al.  A Manual for the Study of Meiofauna. Smithsonian Contributions to Zoology No. 78 , 1972 .

[8]  J. S. Gray,et al.  A manual for the study of meiofauna , 1971 .

[9]  R. Rieger,et al.  Gezeitenbedingte Wanderungen von Turbellarien und Nematoden eines Nordadriatischen Sandstrandes. , 1971 .

[10]  R. Coggeshall A fine structural analysis of the statocyst in Aplysia californica , 1969 .

[11]  K. J. Pedersen CYTOLOGICAL AND CYTOCHEMICAL OBSERVATIONS ON THE MUCOUS GLAND CELLS OF AN ACOEL TURBELLARIAN, CONVOLUTA CONVULIA * , 1965 .

[12]  A. Dorey The organization and replacement of the epidermis in acoelous turbellarians. , 1965, The Quarterly journal of microscopical science.

[13]  H. Helander Morphology of Animal Secretory Gland Cells , 1965 .

[14]  A. Lendrum SECTION CUTTING IN MICROSCOPY , 1962 .

[15]  F. Moore. VI.—Descriptions of three new species of Diurnal Lepidoptera , 1858 .