Helminth Assemblages of the Turtle Emydura macquarii (Pleurodira: Chelidae) Queensland, Australia

Parasites in feral

Feral populations of Chelodina longicollis (Shaw, 1794) have established in Tasmania but many aspects of their biology in the wild remain unknown. A number of C. longicollis specimens were available for examination for parasites. Two species of digenean parasites were found in three of the 11 turtles examined: a Choanocotyle sp. and Thrinascotrema brisbanica Jue Sue & Platt, 1999. This is the first report of parasites from feral turtles in Tasmania. Due to the lack of native populations of freshwater turtles in Tasmania, these parasites must also have been introduced to Tasmania and have established life cycles in the new environments. The implications of such introductions, without suitable definitive hosts available to assist in establishing parasite infections, is discussed. An updated list of digenean parasites reported from Australian freshwater turtles is presented.

Helminth’s assemblage of Trachemys dorbigni (Testudines: Emydidae) in southern Brazil: implications of anthropogenic environments and host’s genders

ABSTRACT The assemblage of helminths of Trachemys dorbigni was analyzed according two environments (rural and urban) and according to host’s gender. Thus, the helminths found were: Spiroxys contortus (Rudolphi, 1819), Falcaustra affinis (Leidy, 1856), Camallanus emydidius Mascarenhas & Müller, 2017, Dioctophyme renale (Goeze, 1782) (larvae), Eustrongylides sp. (larvae) (Nematoda), Telorchis corti (Stunkard, 1915), Telorchis achavali Mañé-Garzón & Holcman-Spector, 1973, Telorchis spp. (Digenea), Polystomoides rohdei Mañé-Garzón & Holcman-Spector,1968 and Neopolystoma sp. (Monogenoidea). Parasitological indices suggests that S. contortus, F. affinis, C. emydidius, T. corti and P. rohdei are species common in helminth assemblage of T. dorbigni in southern Brazil. Infection by Dioctophyme renale is typical of the urban area and suggest relation with eutrophication process and feedback of parasitic cycle in the freshwater urban environment. Parasitological indices of Neopolystoma sp. and T. achavali suggest to be occasional infections; whereas infection by Eustrongylides sp. could be considered accidental. About Telorchiidae, there was no co-occurrence of the species of this group for the examined hosts. In relation to host’s gender, it was observed that infections by S. contortus, F. affinis, C. emydidius and T. corti had higher rates in females, showing a more intimate association with the females of T. dorbigni. The results suggest that human impact on the environment could affect the infrapopulacional dynamics of parasite species influencing the presence and rates of infection of helminths or exacerbating heterogeneities related to host’s gender.

Krefftascaris (Nematoda, Ascaridoidea) from Australian Side-Necked Turtles with Description of Krefftascaris Sharpiloi SP. N. from Chelodina Rugosa

Previously known records of ascaridoid nematodesKrefftascarisSprent, 1980 are summarized and new records of the genus reported.Krefftascaris sharpiloiTkach, Kuzmin et Snyder, sp. n. is described from specimens found in the stomach of the northern snake-necked turtleChelodina rugosacollected from two localities in Northern Territory, Australia. The new species differs from the only previously knownKrefftascarisspecies,K. parmenteriSprent, 1980, by the presence of thickened and bifurcated anterior edges of the lateral cuticular alae and a difference in the relative distance from the anterior end to the nerve ring which is 1.5 to 2 times greater inK. parmenteri.Comparison of approximately 2.100 bases of ribosomal DNA sequences This study contains first reports ofKrefftascarisinChelodina rugosa, Chelodina burrungandjii, Chelodina canniandEmydura tanybaragaand the first records of this genus in the Northern Territory, Queensland and Western Australia. Molecular phylogenetic analysis based on sequences of nuclear small ribosomal subunit gene has demonstrated close affinities betweenKrefftascarisandHeterocheilus, the type genus of the Heterocheilidae and Heterocheilinae. Parasitism of several species and genera of Heterocheilidae in crocodiles allows us to hypothesize thatKrefftascarismay have been acquired by turtles from crocodilians.