Gastrointestinal helminth community of loggerhead sea turtle Caretta caretta in the Adriatic Sea

Abstract

We analysed the intestinal helminth community of 70 loggerhead sea turtles Caretta caretta with a curved carapace length ranging from 25 to 85.4 cm, recovered dead in neritic foraging habitats in the Adriatic Sea in 1995 to 2004. The overall prevalence of infection was high (70.0%), with a mean abundance of 36.8 helminth parasites per turtle. Helminth fauna comprised 5 trematodes (Calycodes anthos, Enodiotrema megachondrus, Orchidasma amphiorchis, Pachypsolus irroratus, Rhytidodes gelatinosus) and 3 nematodes (Sulcascaris sulcata, Anisakis spp., Hysterothylacium sp.), with 6 taxa specific for marine turtles. In terms of infection intensity and parasite abundance, O. amphiorchis was the dominant species (mean intensity: 49.8; mean abundance: 12.8), followed by R. gelatinosus (30.5 and 8.3, respectively) and P. irroratus (23.5 and 7.0, respectively), while larval Anisakis spp. exhibited the highest prevalence (34.3%). The intensity of helminth infection ranged from 1 to 302 (mean: 52.6 ± 69.1) and was not correlated with the size of turtles; this relationship held for all species, except R. gelatinosus (r S = 0.556, p < 0.05). In comparison to other marine habitats, the helminth community of Adriatic loggerheads is characterised by higher species diversity (Shannon-Wiener H' = 1.58) and evenness (E = 0.76), and lower dominance values (Berger-Parker d = 0.35), which can be attributed to the life history and feeding ecology of sea turtles in recruited neritic grounds and the diversity of their benthic prey.

Report of Enodiotrema megachondrus (Looss, 1899) Looss, 1901 (Digenea: Plagiorchiidae) in a green turtle Chelonia mydas Linnaeus, 1758 (Testudines, Cheloniidae) from Brazil

“…This hypothesis is supported by the observation that the largest parasitological indices (prevalence, mean abundance and mean intensity) were found in turtles with small CCL during the study. A similar fact has been observed by other authors in the same host in the Mediterranean Sea (Aznar et al, 1998), the Madeira archipelago (Valente et al, 2009) and the Adriatic Sea (Gracan et al, 2012).…”

“…The author subsequently described E. reductum and E. instar (Looss, 1901) and, in the following year, offered a better description of the two species as well as describing E. acariaeum Looss, 1902(Looss, 1902. Enodiotrema megachondrus is a generalist parasite described in C. mydas (Looss, 1902;Greiner, 2013; presente report), C. caretta (Braun, 1901;Looss, 1901Looss, , 1902Sey, 1977;Aznar et al, 1998;Manfredi et al, 1998;Valente et al, 2009;Santoro et al, 2010;Gracan et al, 2012;Greiner, 2013), Eretmochelys imbricata Linnaeus, 1766 (Groschaft et al, 1977), Lepidochelys olivacea (Eschscholtz, 1829) (Vivaldo et al, 2006;Santoro & Morales, 2007) and Lepidochelys kempii (Garman, 1880) (Greiner, 2013) in different regions of the world. Although E. megachondrus has been described in different hosts, this species has been studied better in C. caretta hosts, especially in regions of Europe (Aznar et al, 1998;Manfredi et al, 1998;Valente et al, 2009;Santoro et al, 2010;Gracan et al, 1012).…”

“…2F). Previous records: In C. caretta from Egypt (Braun, 1901;Looss, 1899); France (Euzet & Combes, 1962); Italy (Manfredi et al, 1998); Mediterranean (Aznar et al, 1998;Santoro et al, 2010); Madera (Valente et al, 2009), Adriatic sea (Gracan et al, 2012) and USA (Greiner, 2013); C. mydas from Egypt (Looss, 1902), USA (Greiner, 2013) and Brazil (Present report); E. imbricata from Cuba (Groschaft et al, 1977); L. olivacea from Mexico (Pérez-Ponce de León et al, 1996;Vivaldo et al, 2006) and Costa Rica (Santoro & Morales, 2007) and L. kempii from and USA (Greiner, 2013).…”

“…In the archipelago of Madeira, Valente et al (2009) performed a parasitological analysis of 57 individuals of C. caretta (CCL range: 15.3 to 61.5 cm) and the presence of E. megachondrus was found in 24.6 % of the hosts, accounting for the second most prevalent parasite, with mean intensity of 7.71 (range: 1 to 31). Analyzing 70 individuals of C. caretta from the Adriatic Sea [mean CCL: 45.0 ± 13.6 cm (range: 25.0 to 85.4 cm)], Gracan et al (2012) found a prevalence rate of 4.3 % (3/70) (confi dence interval: 1.2 to 11.9) and mean intensity of 11.3 (confi dence interval: 11.0 to 11.7). However, the parasites were only found in small juvenile turtles.…”

Helminth Parasites of the Juvenile Hawksbill TurtleEretmochelys imbricata(Testudines: Cheloniidae) in Brazil

“…Studies on parasite communities from sea turtles have been conducted with Lepidochelys olivacea (De León et al, 1996), Caretta caretta (Aznar et al, 1998;Santoro et al, 2010, Gracan et al, 2012Valente et al, 2009) and Chelonia mydas (Santoro et al, 2006). However, until the date of this work there is no E. imbricata parasite communities analysis available in the literature.…”