Macrostomorpha taxonomy and phylogeny

Eyes 13 x 25 micrometer. The penis stylet is bow-shaped, gradually tapering in diameter towards the swollen distal end. The walls of the distal end are slightly thickened; the distal opening is displaced slightly to one side of the swollen end and is not exactly terminal. p. 55

The distal opening is terminal and oblique, facing the concave side of the bow. The walls surrounding the distal opening appear to be very slightly thickened. p. 50

Penis stylet consists of a funnel about 80-98 micrometer in length in slightly squashed specimens, curved in two planes and with a sub-terminal distal opening, the distal end is blunt and cowl (hood) shaped. p. 253

Eyes 8 x 9 micrometer. The distal end of the penis stylet is bent so that the angle between this and the main axis is slightly less than a right-angle. The distal opening is oblique. The walls of the tube are of even thickness. A distinctive notch is present in one of the walls near the proximal opening (D). p. 54

Eyes 10 x 21 micrometer. The penis stylet is typically in the form of a blunt hook. The walls of the tube around the distal terminal opening are very slightly thicker than the walls in the remaining part of the stylet. p. 52

Acerose smooth penis stylet, no chitin valve in the surface. Its far-forth end show helical curly form. The penis stylet is like end of injector, opening at outboard part of helical bend. p. 703

With bean-, cycle-, kidney- or long kidney-like eyes. The end of penis is spinous, twisting vertically from penis plane. p. 720