Gordius gonzalezi, a new species of horsehair worms (Nematomorpha) from Spain Author Schmidt-Rhaesa, Andreas Author Martínez, Jesús text Zootaxa 2016 4103 1 63 67 journal article 37177 10.11646/zootaxa.4103.1.6 f8165b9c-b174-4654-8727-88bde936d5f8 1175-5326 271176 3C5B14A9-A5D1-409A-8192-7A9FDEACDF5B Gordius sp. Locality: Spain , Laguna de los Peces, Sanabria Natural Park, arroyo del Fuego, 1700m , Zamora, Castilla y León, Spain , 42°10´57.59´´N / 6°43´47.98´´W . Collected on October 21, 2014 by J. Martínez. This specimen is a male, 70 mm long with a diameter of 0.4 mm . The body color is medium brown, with a white anterior tip followed by a darkly colored collarThe cuticle is smooth ( Fig. 3A ). In the posterior end a semicircular postcloacal crescent is present which directly borders the point where the two tail lobes separate ( Fig. 3B ). A few fine bristles were found on the inner side of the tail lobes ( Fig. 3C ). The determination of Gordius species is difficult when cuticular characters such as areoles are lacking. From Europe alone, 15 Gordius species with a smooth cuticle have been reported (Schmidt-Rhaesa 2010). The presence and distribution of fine bristles in the posterior end has been used recently to describe new species (Schmidt- Rhaesa 2010, Schmidt-Rhaesa & Prous 2010 ), but the presence of scattered bristles in the region of the tail lobes has been observed in SEM investigations of several specimens and might be a common pattern in several Gordius species. In “older” descriptions such fine bristles are usually not mentioned and were probably overlooked. Therefore, we regard it best to consider this specimen as Gordius sp., with some affinity to Gordius aquaticus .