Relationship between diet and helminths in Gallotia caesaris (Sauria: Lacertidae).

Agama agama, the agamid rainbow lizard, has been reported to serve as transport and reservoir host to several protozoan and helminth parasites. We randomly sampled 310 specimens between May and July, 2005, at Oyingbo, Lagos, Nigeria (6°34'60'' N-3°19'59'' E and 6°34'60'' N-3°19'59'' E).They harboured four species of nematodes: Strongyluris brevicaudata, Parapharyngodon awokoyai, Capillaria sp. and Oxyuris sp.; one of Cestoda, Oochoristica agamae; one of Trematoda, Mesocoelium monas; and one of Pentastomida, Raillietiella sp. Strongyluris brevicaudata had the highest prevalence of infection (82.3 %), followed by P. awokoyai (74.5 %), Raillietiella (10.3 %), Capillaria sp. (8.4 %) and O. agamae (7.4 %). M. monas and Oxyuris sp. had low prevalences: 1.61 % each. Raillietiella sp. and Capillaria sp. can cause localized inflammation and intestinal infections in humans. The prevalence of infection was higher in larger adult lizards. Prevalence in males was 97.6 % (94.1 % in females). In four of the helminth species, intensity of infection was higher in male lizards. Parasite intensity was highest in the rectum, followed by the intestine (p < 0.05). Infection intensity was, to a large extent, dependent on the type of parasite, and age of lizard. During May, P. awokoyai had its highest mean intensities and prevalence. The prevalence and mean intensity of helminthes varied with the month of collection (both p < 0.05). For the three months studied, prevalence and mean intensity of S. brevicaudata were highest in June (July for the other species).

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Helminth parasites of the African lizard Agama agama (Squamata: Agamidae), in Lagos, Nigeria

Diet and helminth fauna were analysed in Gallotia stehlini (Schenkel, 1901), a giant lacertid lizard endemic to Gran Canaria (Canary Islands, Spain) in order to explore eventual relationships between both traits. This species is mainly herbivorous, eating a large proportion of plant matter (occurrence 97.1%) including not only seeds but also leaves and other vegetative parts. Helminth fauna included many helminth species typical of herbivorous reptiles, and intestinal helminth diversity was high. A comparison with other lacertids suggests that both traits, diet and helminth fauna, result from an adaptation to insular conditions. Canarian Gallotia, a separate lineage evolving for a long time in insularity, constitutes the most modified lacertid group in this sense.

/pdf/diet-and-helminth-parasites-in-the-gran-canaria-giant-lizard-2g9lhfzaac.pdf

Diet and helminth parasites in the Gran Canaria giant lizard, Gallotia stehlini

A survey of helminth communities of Gallotia atlantica (Peters et Doria, 1882), from Lanzarote and Fuerteventura islands, in the Canary Archipelago, Spain, was conducted in order to determine the prevalence, intensity, and diversity of parasites of these lacertid lizards. Larval cestodes were found in the body cavity of hosts from Lanzarote. Spauligodon atlanticus was the only core species in the helminth component community of G. atlantica. Helminth infracommunities of both host populations were depauperate and isolationist.

/pdf/helminths-of-the-atlantic-lizard-gallotia-atlantica-reptilia-2bcp40mdca.pdf

Helminths of the Atlantic lizard, Gallotia atlantica [Reptilia, Lacertidae], in the Canary Islands [Eastern Atlantic]: Composition and structure of component communities

Understanding how parasite communities are assembled, and the factors that influence their richness, can improve our knowledge of parasite-host interactions and help to predict the spread of infectious diseases. Previous comparative analyses have found significant influences of host ecology and life history, but focused on a few select host taxa. Host diet and habitat use play key roles in the acquisition of parasitic helminths as many are trophically transmitted, making these attributes potentially key indicators of infection risk. Given the paucity of comparative studies with non-piscine, non-avian or non-mammalian hosts, it is critical to examine the degree to which host ecology influences parasite communities in other host taxa in order to identify common drivers. We examined helminth diversity in over 350 species of lizards in relation to their body mass, ecology (diet and habitat use) and life history (clutch size, and ovo- or viviparity) using previously published data. Overall, lizard species with herbivorous diets harboured fewer types of helminths (especially larval stages), with similar results for traits that were ultimately strongly associated with diet (host mass and habitat use). Large hosts tended to be herbivores with few helminth types, whereas species utilizing arboreal habitats typically consumed some animal matter and hosted more helminths. Understanding how host ecology and life history are related to their parasite assemblages has significant implications for the risk of acquiring novel parasites. Our results indicate an overwhelming influence of host diet such that many helminths may be relatively easily acquired by hosts in new ranges, or through dietary shifts.

https://besjournals.onlinelibrary.wiley.com/doi/pdf/10.1111/1365-2656.12934

Your infections are what you eat: How host ecology shapes the helminth parasite communities of lizards.

A survey of gastro-intestinal helminth communities of Gallotia stehlini (Sauria: Lacertidae) from Gran Canaria island (Canary Archipelago, Spain), was conducted to determine the prevalence, abundance and species diversity of intestinal parasites in these lizards. Pharyngodonid nematodes were the most common intestinal helminths, three species being Gallotia specialists. Helminth infracommunities of G. stehlini were rich and appear to be closer to the interactive end of the continuum isolationist-interactive helminth communities, according to the high values of helminth diversity. It is the first case of a saurian reptile showing this kind of diverse helminth infracommunity, produced by a large size, a wide-ranging plant diet and exposure to helminths with direct life-cycles.

V. Roca

Papers

Helminth infracommunities of a population of the Gran Canaria giant lizard Gallotia stehlini.