Spirocerca lupi in the stomach of two Andean foxes (Lycalopex culpaeus) from Chile

Sophia Di Cataldo, Aitor Cevidanes, Paulina Sepúlveda-García, Mario Alvarado-Rybak, Riccardo Paolo Lia, Domenico Otranto, Karen Terio, Ananda Müller, Javier Millán

Research output: Contribution to journalArticlepeer-review


The genus Spirocerca includes nematodes that parasitize the stomach and the oesophagus of carnivores, chiefly canids. Herein, we provide new data about the morphological, histopathological, and molecular characterization of Spirocerca sp. in Andean foxes (Lycalopex culpaeus) in Chile. Intact immature worms, identified as Spirocerca sp., were recovered in the lumen of the stomach from two foxes. Histologically, worms morphologically consistent with spirurid nematodes were present within the wall of the stomach and surrounded by nodular areas of inflammation with central necrotic debris. Molecular analysis of the cox1 gene yielded 19 sequences and 5 nucleotide sequence types with 99.95 to 99.98% similarity, being shared between both foxes. Nucleotide similarity ranged from 93.1 (with genotype 2 of S. lupi and S. vulpis) to 95.8% (with genotype 1 of S. lupi), a higher similarity than noted from sequences of S. lupi from an Andean fox from Peru (91.0 to 93.3%). However, the Poisson Tree Processes for species delineation did not support the existence of a new species Spirocerca. Phylogenetic and nucleotide analyses suggest that these specimens belong to a new variant or genotype of S. lupi or to a cryptic species. Whether the presence of the worms in the stomach has to do with genotypic differences in parasites or host or some combination is uncertain. Spirocerca lupi has never been found in Chilean dogs and must be investigated.

Original languageEnglish (US)
Pages (from-to)1261-1269
Number of pages9
JournalParasitology Research
Issue number6
StatePublished - Jun 2023


  • Culpeo fox
  • Nematoda
  • Pseudalopex culpaeus
  • South America
  • Spirurida

ASJC Scopus subject areas

  • veterinary(all)
  • Insect Science
  • Infectious Diseases
  • Parasitology


Dive into the research topics of 'Spirocerca lupi in the stomach of two Andean foxes (Lycalopex culpaeus) from Chile'. Together they form a unique fingerprint.

Cite this