Gordius karwendeli, Schmidt-Rhaesa, Andreas, 2010

Schmidt-Rhaesa, Andreas, 2010, Considerations on the genus Gordius (Nematomorpha, horsehair worms), with the description of seven new species, Zootaxa 2533, pp. 1-35 : 24-25

Gordius karwendeli sp. nov.

( Fig. 9A–C , 11 B)

Type material: Holotype: 13, Zoological Museum Hamburg, ZMH V13273 .

Type locality. Germany, Karwendel Mountains, 4–4.5 km NE of Mittenwald. Found in a (not water covered) gravel-bed along stream Seinsbach at roadside during heavy rains (coll. June 25, 2002 by Maaike van Rijn and Axel Groenveld).

Other material examined. No further material.

Etymology. The name refers to the sampling locality in the Karwendel Mountains which are part of the Alps.

Description. The body color is creamy white; white spots, dark median lines and the dark collar are absent. The specimen is 135 mm long and has a diameter of 0.4 mm.

The postcloacal crescent is slightly parabolic and quite short ( Fig. 9A ). It is directly at the point of bifurcation, but extends only slightly onto the tail lobes. The tail lobes are slightly longer than twice their diameter. The inner side of the tail lobes is slightly concave, but only in the distal half. The proximal, inner region of the tail lobes, i.e. directly posterior to the postcloacal crescent and extending along about the first half of the tail lobes the cuticle is completely smooth ( Fig. 9A,B ). Scattered bristles are present, with exception of the smooth region, on the entire posterior end ( Fig. 9A ). Directly posterior to the tips of the postcloacal crescent the bristles are denser than in the remaining regions and mark the upper border of the smooth region ( Fig. 9A,B ; 11B).

The cuticle contains flat polygonal areoles ( Fig. 9C ).

Remarks. The combination of a smooth region on the tail lobes and a denser “line” of bristles on its ventral border is unique among Gordius species. There is some resemblance to G. borisphenicus and G. helveticus , which are discussed above (see remarks of G. helveticus ).

Figures

FIGURE 11. Schematic drawing indicating the differences in the distribution of bristles and spines in the posterior end of A. G. helveticus, B. G. karwendeli and C. G. zwicki.

FIGURE 9. A – C. Gordius karwendeli sp. nov., D – E. G. p e s i c i sp. nov. A. Posterior end. B. Magnification from the posterior end showing smooth region on the inner side of the tail lobes and characteristic arrangement of bristles. C. Polygonal regionalization of the cuticular surface. D. Posterior end. E. Structure of the cuticle.