Rogneda tripalmata (Beklemischev, 1927) Karling, 1953

Artois, Tom J., 2008, Revision of Rogneda Uljanin, 1870 (Rhabditophora, Eukalyptorhynchia, Polycystididae) with the description of seven new species, Zoological Journal of the Linnean Society 153 (1), pp. 1-28 : 7

THE TRIPALMATA -GROUP

The tripalmata -group includes two Mediterranean species with two dorsal pigment stripes: R. tripalmata ( Fig. 10C ) and R. valckei ( Figs 10A, B , 12A, B ). Both species are characterized by the unique construction of stylet A, which is no more than a slender plate carrying a spine. This spine is situated at about the midpoint of the stylet in R. tripalmata , more distally in R. valckei . Stylet B is of the normal construction. Because of the lack of material of R. tripalmata , a direct comparison between the species on the detailed structure of stylet B is impossible. Judging from the drawing by Ax (1959; here Fig. 10C ), R. tripalmata differs from R. valckei in that its plate B1 lacks a serrated distal rim and also lacks the small hook just proximal from this rim. Moreover, R. tripalmata also lacks a hook on plate B2. These observations should, however, be confirmed on new material of R. tripalmata .

Figures

Figure 10. Stylets of the representatives of the tripalmata-group. A, B, R. valckei sp. nov. (A from a paratype, B from the holotype). C, R. tripalmata (after Ax 1959, no scale bar provided). Stylet A is indicated by an A, stylet B by a B. Plates B1 and B2 are indicated by a 1 and a 2, respectively. Scale bar = 25 Mm.

Figure 12. Habitus and stylets of R. valckei sp. nov. and stylets of representatives of the westbladi-group. A, B, R. valckei sp. nov. (A, habitus from a paratype, B stylets from a paratype). C, stylets of R. anglica (from a specimen from Kristineberg). D, E, R. colpaerti sp. nov. (D, stylet B. E, stylet A). Abbreviations: x–z, see text. Arrows: see text.