Acta Parasitologica, Vol. 51, No. 2, 2006, 130-135 Xavier Santos(1,2)*, Fernando Martinez-Freiria(3), Juan M. Pleguezuelos(1) and Vicente Roca(4) - First helminthological data on Iberian vipers:
Helminth communities and host-parasite relationships
(1)Departamento de Biologia Animal y Ecologia, Facultad de Ciencias, Universidad de Granada, 18071 Granada, (2)Departamento
de Biologia Animal, Facultad de Biologia, Universidad de Barcelona, Avgda. Diagonal 645, 08028 Barcelona,
(3)Departamento de Biologia Animal, Facultad de Biologia, Universidad de Salamanca, Campus Miguel de Unamuno, Edificio de
Farmacia, 37007 Salamanca, (4)Departamento de Zoologia, Facultad de Ciencias Biologicas, Universidad de Valencia, C/Dr. Moliner 50,
46100 Burjassot, Valencia; Spain
*Corresponding author: xsantos1@ugr.es
ABSTRACT
European vipers are ambush predators with sporadic feeding events, thereby maintaining the digestive tract empty for long periods.
According to previous studies relating lizards' dietary habits and their helminth faunas, we predict poor gastrointestinal
helminth communities in vipers. To test this hypothesis, we have examined the digestive tract of 86 specimens of Vipera aspis
(L., 1758) and V. latastei Bosca, 1878, from several localities of the Iberian Peninsula. We found adults of only two nematode
species Kalicephalus viperae (Rud., 1819) and Ophidascaris sp. and cysts adhering to the external wall on the stomach in case
of two other nematode species Ascarops strongylina (Rud., 1819) and Spirurida gen. sp. All these nematodes are common parasite
species in snakes, although Ophidascaris sp. has never before been recorded in Vipera sp. The low prevalence and small
number of parasite species in Iberian vipers matched their low feeding rates. However, our results contrast with studies in Poland
and Belarus of V. berus species, in which nematodes, as well as trematodes, are common and abundant. Rainfall rates are lower
in the Iberian Peninsula than in eastern Central Europe, where amphibians are more available and consumed by V. berus.
Amphibians, intermediate hosts for these helminths, have been recorded only sporadically as prey for V. aspis and V. latastei,
thus supporting the absence of trematodes in both Iberian viper species. Among populations of Iberian vipers, the prevalence
of parasites correlates with the feeding rate (i.e. percentage of vipers with prey), suggesting a linkage between the two parameters.
In conclusion, our results suggest that several factors, including climatic characteristics of localities, feeding rates of predators,
and type of prey consumed, influence the number and type of parasites in Iberian vipers.
KEY WORDS: Vipera aspis, V. latastei, helminths, nematodes, parasitism, Iberian Peninsula