Morphological characterization of two new species of Dicontophrya (Ciliophora: Astomatia: Contophryidae) commensal of earthworms (Oligochaeta: Annelida) of Ebebda and Nkolbikogo (Cameroon)
Résumé
Two new species of astomatous ciliates (Dicontophrya minus n. sp. and Dicontophrya ebebdaensis n. sp.) endocommensal of Glossoscolecidae earthworms pertaining to the genus Alma are described using light-microscopy and a combination of staining techniques (pyridinated ammoniacal silver nitrate and DAPI). Studies reveal the existence of two distinct morphological types as evidence of morphological diversification within the genus Dicontophrya de Puytorac and Dragesco, 1969. In the first morphological type represented by Dicontophrya minus n. sp., the cell is ovoid (90×125-35×115 µm) with a ribbon like axial macronucleus flanked with a relatively big micronucleus (6.2 µm in diameter). In the second morphological type (Dicontophrya ebebdaensis n. sp.), the cell is elongated and wormlike (180×215-35×50 µm) with a nuclear apparatus composed of a long ribbon shape macronucleus (171.1 µm), bearing in its posterior half a globulous micronucleus. In the two cases cells bear in the anterior end a depression in which lodges a skeletal apparatus build in the same plan of organization (a modified V shaped skeletal branch bearing about 7 skeletal fibers) that characterize the genus.