Gordius balcanicus, 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 : 22

Gordius balcanicus sp. nov.

( Fig. 7 A–C)

Type material: Holotype: 13, Zoological Museum Hamburg, ZMH V13270 .

Type locality. Serbia, Kučaj Mountains, Dubašnica, Mikuljska River (coll. October 3, 2006) by Ajtić.

Other material examined. No further material.

Etymology. The name refers to the region of the Balcans, where this species was collected.

Description. The body color is light brown; white spots are present on the cuticle, but weakly visible. The anterior end includes a white tip followed by a black collar. Dorsal or ventral dark lines are not present. The specimen is 235 mm long and has a diameter of 0.8 mm.

The postcloacal crescent is slightly angled ( Fig. 7 A). The cloacal opening and the region posterior to the postcloacal crescent are covered by contamination, but it appears that the crescent is directly at the point of bifurcation. The arms of the crescent extend onto the first third of the tail lobes ( Fig. 7 A). The tail lobes are about twice as long as broad, their inner side is slightly concave. Scattered tiny bristles are present on the entire posterior end ( Fig. 7 A).

The cuticle does not contain recognizable areoles, but a system of grooves separating the cuticle into branching ridges ( Fig. 7 B,C). These ridges are oriented perpendicular to the longitudinal axis of the animal. They branch and fuse with other ridges in a random manner ( Fig. 7 C).

Remarks. There are a few species for which ridge-like cuticular elements perpendicular to the body axis have been described. Such ridges are narrow or have a sharp apical edge in G. austrinus de Villalobos, Zanca & Ibarra-Vidal, 2005 from Chile (de Villalobos et al. 2005) and G. plicatulus Heinze, 1937 from Germany, Spain and Croatia ( Heinze 1937; Čanadjija 1956; de Villalobos et al. 2001). The broad ridges of the new species have some resemblance to those of G. g e s n e r i Heinze, 1937 from Germany and Croatia ( Heinze 1937; Čanadjija 1956), but in this species characteristic indentations of the inner side of the tail lobes have been reported (these indentations do not resemble the concave state of tail lobes, but should be documented in more detail). Therefore, this specimen is considered to represent a new species.

Figures

FIGURE 7. Gordius balcanicus and G. digitatus. A – C. Gordius balcanicus sp. nov., D – E. G. digitatus sp. nov. A, E. Posterior ends. B. Cuticle under low magnification. C. Cuticle showing broad ridges separated by grooves. D. Cuticle showing irregular shape of areoles.