Abstract
Following the detection of
Brachylaima
spp., which are potentially pathogenic for domestic animals and humans, in
Cornu aspersum
and
Cepaea nemoralis
at a rural site in France, we investigated trematode distribution among sympatric gastropod species to assess their role in the parasite life cycle. Eight species were investigated (
Cepaea nemoralis
,
Cernuella neglecta, Clausilia bidentata
,
Cochlicella acuta, Cornu aspersum
,
Lauria cylindracea, Pomatias elegans
, and
Theba pisana
). Four species were parasitised by trematodes:
C. aspersum
(prevalence 56%),
C. nemoralis
(10%), and
T. pisana
(2%) as second intermediate hosts of
Brachylaima
spp., and
C. neglecta
(6%) as new first intermediate host of
Pseudoleucochloridium
sp. Moreover, we observed for the first time shell-encapsulation of trematodes in a non-helicid species (
C. neglecta
) and nematodes in a non-stylommatophoran species (
P. elegans
), suggesting more general anti-parasite defence than previously thought among land snails. Our current and previous results, including molecular data (28S rDNA, COI mtDNA), suggest the occurrence of four
Brachylaima
species at the site:
Brachylaima mesostoma
and three unidentified species.
Cornu aspersum
is the only identified first intermediate host for
B. mesostoma
and one of the unidentified trematode species also found at a metacercarial stage in
C. aspersum
and
C. nemoralis
. Another unidentified species recorded in
C. aspersum
and
C. nemoralis
, characterised by small orange metacercariae, may be a new species. The sole metacercaria found in
T. pisana
may also belong to an undescribed species.