Heligmosomoides neopolygyrus Asakawa & Ohbayashi, 1986, a cryptic Asian nematode infecting the striped field mouse Apodemus agrarius in Central Europe

Abstract

Background: Heligmosomoides polygyrus is a widespread gastro-intestinal nematode infecting wild Apodemus (wood mice) throughout Europe. Using molecular and morphological evidence, we review the status of Heligmosomoides from Apodemus agrarius in Poland previously considered to be an outlying clade of H. polygyrus, to further resolve the status of the laboratory model species, H. bakeri. Methods: Morphological analysis of the male bursa and the synlophe, and molecular analyses of concatenated nuclear (28S rDNA, ITS1 and ITS2) and mitochondrial (CO1 and cytb) genes, of Heligmosomoides collected from Apodemus agrarius from two sites in Poland and comparison with related heligmosomids from voles and mice in Eurasia. Results: Heligmosomoides neopolygyrus, a heligmosomid nematode from Apodemus species from China and Japan, is recognised for the first time in western Europe infecting Apodemus agrarius in Poland. It can be distinguished from H. polygyrus by the filiform externo-dorsal rays of the male copulatory bursa and the small, equally distributed longitudinal crêtes on the body. Specimens from A. agrarius are 20% different at ribosomal (ITS1 and ITS2) nuclear loci, and 10% different at the mitochondrial cytb locus from H. polygyrus, and in phylogenetic analyses group with the vole-infecting genus Heligmosomum. Conclusions: Despite morphological similarity, H. neopolygyrus is only distantly related to H. polygyrus from western European Apodemus, and may be more closely related to vole-infecting taxa. It was brought into Europe by the recent rapid migration of the host mice. Inclusion of H. neopolygyrus in phylogenies makes it clear that Heligmosomoides is paraphyletic, with the pika-infecting Ohbayashinema and the vole-infecting Heligmosomum nesting within it. Clarification of the European status of H. neopolygyrus also allows H. bakeri, the laboratory model species, to be seen as a terminal sister clade to H. polygyrus, rather than as an internal clade of the latter taxon.

Parasitic nematodes of the genusSyphaciaSeurat, 1916 infecting Muridae in the British Isles, and the peculiar case ofSyphacia frederici

“…The eastern Asian nematode fauna differs in many respects to that found in western Europe (e.g. the genus Aspiculuris , see Behnke et al 2015, or Heligmosomoides , see Zaleśny et al 2014), and there is no a priori reason to suspect that Syphacia from Japan and western Europe should be conspecific. Moreover, A. speciosus , the host of S .…”

“…Nottingham in the centre and Berkshire in the central south of the British Isles, and Anglesey in the north-west tip of Wales). It may of course be more widespread, or indeed show a patchy distribution across the British Isles since Apodemus populations in the British Isles and Ireland originated in a variety of ways, including from potential southern refugia (Montgomery et al 2014) and from synanthropic transfer with colonizing or invading humans (Berry, 1973; Yalden, 1999), and their parasites originated with them; Heligmosomoides polygyrus of two quite distinct mitochondrial haplotypes occur within the British Isles, for example, one widespread in western Europe, while the other has been found only in Britain, Ireland and Denmark (Nieberding et al 2005; Cable et al 2006; Zaleśny et al 2014). A heterogeneous distribution of Syphacia species might therefore be expected, but further relevant fieldwork must be conducted to elucidate these patterns.…”

Genetic diversity of Bartonella genotypes found in the striped field mouse (Apodemus agrarius) in Central Europe

“…A. agrarius is a recent immigrant to Europe, spreading west with the development of agriculture over the past 1000 years (Kowalski, 2001), and it has brought with it a number of unique parasites (Zalesny et al 2014) otherwise known only from Eastern Asia. The B. clarridgeiae / rochalimae and B. elizabethae / tribocorum clades infecting A. agrarius appear to lack genetic diversity when compared with e.g.…”

Effects of Climate and Rodent Factors on Hemorrhagic Fever with Renal Syndrome in Chongqing, China, 1997–2008

“…In addition, high temperature may limit the time for outdoor activity and work, thereby reducing the opportunity for contact between people and the striped field mouse ( A . agrarius ), which is one of the most common agricultural pests and a natural vector of hantavirus [ 23 , 24 ]. However, inconsistent findings have been reported in other studies indicating a positive association between temperature and HFRS incidence [ 25 , 26 ].…”