Dirk De Waele

Tissue treatment for whole mount internal lectin staining in the nematodes Caenorhabditis elegans, Panagrolaimus superbus and Acrobeloides maximus

Four different fixation schemes, using ten fluorescent-labelled lectins, were investigated for whole mount internal staining of three rhabditid nematodes: Caenorhabditis elegans, Panagrolaimus superbus and Acrobeloides maximus. Acetone-only fixation was found to give strong and reproducible staining, which could be prevented either by periodate treatment of the organisms or by specific inhibitory sugars of the lectins under investigation. Whereas the use of either phosphate or TRIS buffers had no effect on the staining pattern or the fluorescence intensity, the incubation time as well as the incubation temperature affected the staining reaction. The best results were obtained upon overnight incubation at 4° C: the lectin staining could be inhibited in all cases, except for the intestinal brush border of C. elegans by the lectin of Lens culinaris.

Species of Aphanolaimus (Nematoda, Araeolaimida) from Africa

Aphanolaimus louisae sp.n. from mountain lakes on Mt. Kenya is described and figured in detail. Examination by scanning electron microscopy revealed some interesting morphological characters, such as the structure of the amphideal fovea, extremely small mouth opening, cuticular striation, lateral field, cuticular pores and setae and male supplements. A. louisae most closely resembles A. aquaticus Daday, 1894, but differs in the number of preanal supplements and shape of the spicules. A specimen from Zaïre comes close to the new species and is described as Aphanolaimus sp. Finally A. microlaimus De Coninck, 1935 is redescribed on the basis of the type material.