title: Morphology and aspects of growth of a trypanosome transmitted by the marine leech Johanssonia arctica (Piscicolidae) from Northern Norway.
abstract: The fish leech Johanssonia arctica (Johansson, 1898) was collected from king crabs Paralithodes camtschaticus (Tilesius, 1815) in Finnmark, N Norway, and allowed to feed on experimental fish hosts in the laboratory. This leech ingested blood from laboratory-reared cod (Gadus morhua) and halibut (Hippoglossus hippoglossus). Some experimental halibut acquired trypanosome infection, with parasitaemia between ca. 500 and 60,000 trypanosomes ml(-1). The trypanosomes were of variable size and measured 39-90 microm (mean 57 microm) ca. 81 days post-infection. Characteristic features are cell striation, refractile cytoplasmic granules, anterior nucleus and a relatively long (ca. 6 microm, max 9 microm) distance from the posterior end to the kinetoplast. Following growth, the trypanosomes became increasingly slender, with fewer striae and a nucleus position less pronounced anterior. The trypanosome is considered distinct from a type transmitted by the leech Calliobdella nodulifera (Malm, 1863) in the NE Atlantic, but is regarded conspecific with a trypanosome transmitted by J. arctica in the NW Atlantic. This trypanosome has in the past been identified as Trypanosoma murmanensis Nikitin, 1927, a poorly described species. T. murmanensis cannot be recognized with certainty among the trypanosomes transmitted by C. nodulifera and J. arctica respectively. We propose that the J. arctica-transmitted species is considered T. murmanensis Nikitin, 1927 sensu stricto.
authors.affiliation: University of Bergen, Department of Biology, Norway. egil.karlsbakk@bio.uib.no
authors.forename: Egil
authors.initials: E
authors.lastname: Karlsbakk
authors.forename: Eli
authors.initials: E
authors.lastname: Haugen
authors.forename: Are
authors.initials: A
authors.lastname: Nylund
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001837:Body Weights and Measures; D005399:Fishes / Q000469:parasitology*; D007865:Leeches / Q000469:parasitology*; D009664:Norway; D013045:Species Specificity; D014345:Trypanosoma / Q000145:classification / Q000166:cytology* / Q000254:growth & development*