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