Notas / Notes


First record of Gordius albopunctatus Müller, 1927 in the Iberian Peninsula (Nematomorpha: Gordioida Rauther, 1930)

Andreas Schmidt-Rhaesa1, Juan E. Expósito López De Felipe2 & Jesús Martínez3

1 Centrum für Naturkunde, University Hamburg, Martin-Luther-King-Platz 3, 20146 Hamburg, Germany
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2 C/ Rembrandt, 6, portal 4, 1°B. Seseña. Toledo, Castilla La Mancha, Spain
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3 Facultad de Biología, Universidad de Santiago de Compostela, Rúa Lope Gómez de Marzoa, s/n., Campus Vida, 15782 Santiago de Compostela, Spain
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Gordius albopunctatus Müller, 1927 (Gordioida) is reported for the first time from the Iberian Peninsula, based on one male and one female specimen collected in the Guadarrama Range (Madrid). This record is the southernmost of this species, notably expanding its known biogeographic range.

Keywords: Nematomorpha; Gordius; faunistics; Madrid; Spain; Iberian Peninsula.



Primera cita de Gordius albopunctatus Müller, 1927 en la Península Ibérica (Nematomorpha: Gordioida Rauther, 1930)

Se hace referencia a la primera cita de Gordius albopunctatus Müller, 1927 (Gordioida) de la península ibérica, a partir de un ejemplar macho y otro hembra capturados en la Sierra de Guadarrama (Madrid). Esta cita es la más meridional de su distribución de modo que se amplía notablemente su distribución biogeográfica.

Palabras clave: Nematomorpha; Gordius; faunística; Madrid; España; península ibérica.


Recibido/Received: 29/05/2020; Aceptado/Accepted: 17/12/2020; Publicado en línea/Published online: 21/05/2021

Cómo citar este artículo / Citation: Schmidt-Rhaesa, A., Expósito López De Felipe, J. E. & Martínez, J. 2021. First record of Gordius albopunctatus Müller, 1927 in the Iberian Peninsula (Nematomorpha: Gordioida Rauther, 1930). Graellsia, 77(1): e134.

Copyright: © 2021 SAM & CSIC. This is an open-access article distributed under the terms of the Creative Commons Attribution 4.0 International (CC BY 4.0) License.







Horsehair worms (Phylum Nematomorpha) are worms with life cycles including a parasitic phase in the body cavity of terrestrial insects, mainly beetles, crickets or praying mantids. Few species develop in aquatic insects, e.g. Gordius albopunctatus Müller, 1927 (see Schmidt-Rhaesa & Kristensen, 2006). At maturity, they leave their host and reproduce in freshwater (5 species are marine), where they lay eggs, from which larvae hatch and infect aquatic paratenic hosts (Hanelt et al., 2005; Schmidt-Rhaesa, 2013).

To date, only five studies have examined Nematomorpha from the Iberian Peninsula. Baker (1985) reported a single undetermined specimen; later, De Villalobos et al. (2001) reported four species (Gordius aquaticus Linnaeus, 1758, Gordius plicatulus Heinze, 1937, Gordionus wolterstorffii Camerano, 1888 and Paragordius tricuspidatus Dufour, 1828) and Schmidt-Rhaesa & Cieslak (2008) added two new species: Gordionus barbatus and Paragordionus ibericus. Recently Schmidt-Rhaesa & Martínez (2016) described the species Gordius gonzalezi, from material collected in the region of Extremadura. Gerlach (1978) cited an additional four species from the Iberian fauna but without any further information on the locality of collection, deposition of voucher material or reference. In this note we present a new record of the species Gordius albopunctatus Müller, 1927 to be added to the Iberian fauna.

Material studied: 1 ♂, 1 ♀ of Gordius albopunctatus Müller, 1927. Locality: Rascafría, puente del Perdón, río Lozoya. Madrid. Guadarrama Range, Sistema Central. Date of collection: 22.08.2019. Leg. J.E. Expósito López de Felipe. Det. A. Schmidt-Rhaesa. Deposited in the Zoological Museum Hamburg (ZMH) (accession number ♀: ZMH V13460; accession number ♂ ZMH-V13461). The specimen was collected manually in the riverside and transferred to ethanol (70%). Pieces of the midbody region and the posterior end of the male were dehydrated in an increasing ethanol series, critical point dried and coated with gold in a sputter coater. Observations were made using a LEO scanning electron microscope (SEM) 1524.

The diagnosis of the species is made by a combination of two characters according to Schmidt-Rhaesa & Kristensen (2006): the presence of white dots (hence the specific name, albopunctatus) and polygonal areoles on the cuticle (Fig. 1A-C). The posterior end of the male (Fig. 1D) has the postcloacal crescent characteristic for the genus Gordius. Interestingly, while most species of Gordius develop in terrestrial hosts, this species has been exclusively reported from aquatic hosts, including caddisflies (Trichoptera), especially Potamophylax cingulatus (Stephens, 1837) (Schmidt-Rhaesa & Kristensen, 2006) and Potamophylax latipennis (Curtis, 1834) (in Heinze, 1941 as Stenophylax stellatus Curtis, 1834).

Fig. 1.—Gordius albopunctatus. A: Overview of the cuticle in midbody in male specimen. B: Magnification of the cuticle in midbody in male specimen. C: Adult cuticle with areoles still partly covered by the larval cuticle of the female specimen. D: Ventral view of the posterior end of the male with the semicircular postcloacal crescent (pcc).

Fig. 1.—Gordius albopunctatus. A: Vista general de la cutícula en la parte media del cuerpo del macho. B: Ampliación de la cutícula en la parte media del cuerpo del macho. C: Cutícula adulta con areolas todavía parcialmente cubiertas por la cutícula larvaria de la hembra. D: vista ventral del extremo posterior del macho con la media luna postcloacal semicircular (pcc).


This record notably widens the distribution of this species towards southern Europe (currently is cited in Germany, Poland and Belgium) (Schmidt-Rhaesa, 2010, 2013).

Although the ecological importance of horsehair worms in freshwater ecosystems has been underestimated in many limnological studies, recent studies have shown this group plays a significant role in terrestrial and aquatic ecosystems. Specifically, they are relevant in the energy flow between terrestrial and aquatic trophic nets and in modifying the seasonality of spatial energy subsidies, which can be important for the dynamics of the community (Sato et al. 2008, 2011, 2012; Takimoto et al. 2009).


We are grateful to Prof. Arun K. Yadav and to an anonymous reviewer for their detailed and interesting suggestions and critical review of the manuscript.


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