Revision of the genus Chordodes (Gordiida, Nematomorpha) from Africa—I. Ultrastructural redescription of Chordodes gariazzi Camerano, 1902, C. heinzei Sciacchitano, 1937, C. kolensis Sciacchitano, 1933, C. muelleri Sciacchitano, 1937, and C. ruandensis Sciacchitano, 1937

Abstract

Thirty‐five species of Chordodes have been reported from Africa. The original description of several of these species is incomplete and needs reinvestigation by scanning electron microscopy (SEM) which allows the observation of fine structural details. We reinvestigated five of these species: Chordodes gariazzi, C. heinzei, C. kolensis, C. muelleri, and C. ruandensis. All of them show crowned areoles occurring in clusters. These clusters are formed by crowned areoles that are surrounded by another areolar type. The females of C. kolensis and C. muelleri have polymorphic crowned areoles with both short and long filaments; these areoles are only observed along the ventral groove. Chordodes gariazzi, C. heinzei, and C. muelleri have five areole types, C. ruandensis has three different types of areole, and C. kolensis displays a sexual dimorphism where males have six types of areole and females have seven areole types. Chordodes gariazzi, C heinzei, and C. muelleri have tubercle areoles. Host data and a new distribution record of C. kolensis are reported.

Keywords:

• Africa
• Gordiida
• Nematomorpha
• scanning electron microscopy

Acknowledgements

To Lisa Levi (Museo Regionale di Science Naturali, Torino, Italy) and to Rudy Jocqué (Africa Museum Tervuren, Belgium; Koninklijk Museum voor Midden‐Afrika) for loaning and giving permission to investigate museum specimens. To Patricia Sarmiento from the Scanning Electron Microscopy Service (Museo de Ciencias Naturales, La Plata, Argentina) for preparation of the material. Many thanks also to two anonymous reviewers for constructive comments on the manuscript.