Genetic variability in Hysterothylacium aduncum, a raphidascarid nematode isolated from sprat (Sprattus sprattus) of different geographical areas of the northeastern Atlantic.
Species of the genus Hysterothylacium are among the most common marine nematode fish parasites in the northern Atlantic. Due to recent findings of cryptic speciation in other parasitic ascaridoid nematodes, a similar pattern of sibling species was hypothesized also for Hysterothylacium aduncum. By investigating a 886- to 890-bp-long genomic DNA fragment including ITS-1, 5.8S rDNA and ITS-2 of 40 specimens of H. aduncum of sprat (Sprattus sprattus) of four different biogeographical regions (North Sea, English Channel, Bay of Biscay, Adriatic Sea), we could not detect significant genetic variability and therefore cryptic speciation. Nevertheless, while ITS-1 and 5.8S rDNA sequences were identical for all analysed specimens, ITS-2 sequences showed a population-specific pattern with the differentiation of an English Channel/Bay of Biscay group from a North Sea/Mediterranean Sea group.
Institute of Zoomorphology, Cell Biology and Parasitology, Heinrich-Heine-University Düsseldorf, Universitätsstrasse 1, 40225, Düsseldorf, Germany. Sven.Klimpel@uni-duesseldorf.de
Sven
S
Klimpel
Sonja
S
Kleinertz
Reinhold
R
Hanel
Sonja
S
Rückert
D000818:Animals; D017191:Ascaridida Infections / Q000469:parasitology*; D001199:Ascaridoidea / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification*; D001267:Atlantic Ocean; D001483:Base Sequence; D043344:Chordata / Q000469:parasitology*; D018509:DNA, Helminth / Q000235:genetics; D004275:DNA, Ribosomal / Q000235:genetics; D021903:DNA, Ribosomal Spacer / Q000235:genetics; D005393:Fish Diseases / Q000469:parasitology*; D008969:Molecular Sequence Data; D011110:Polymorphism, Genetic; D012340:RNA, Ribosomal, 5.8S / Q000235:genetics; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA
D018509:DNA, Helminth; D004275:DNA, Ribosomal; D021903:DNA, Ribosomal Spacer; D012340:RNA, Ribosomal, 5.8S