- Of 2,122 marine fishes belonging to 36 species collected in the
vicinity of Newport, Oregon, 541 belonging to 8 species were infected
with hemoflagellates. Four species of trypanosomes and three species
of cryptobias were found in offshore fishes, but no hemoflagellates
were observed in fishes from Yaquina Bay.
Trypanosoma pacifica was found in 177 of 1,102 Parophrys
vetulus, 3 of 84 Citharichthys sordidus, and 1 of 35 Lyopsetta exilis,
and survived in 10 other species after intraperitoneal injection. The
host-specificity observed in nature was probably the result of selective
feeding by the leech vector, possibly Oceanobdella sp. or Johanssonia
sp. Division stages of T. pacifica were observed in the fish host and
described. The growth rate of juvenile P. vetulus injected with T.
pacifica was less than that of uninfected individuals for a 10 week
period, after which the growth rates of the two groups were
Trypanosoma gargantua was found in 3 of 7 Raja binoculata and
the vector was shown to be the leech Orientobdella sp.
Two unidentified trypanosomes were observed, one from 21 of
1,102 P. vetulus, 24 of 303 Eopsetta jordani, and 6 of 61 Microstomus
pacificus, and the other from 4 of 35 L. exilis.
A small, active cryptobiid was found in 106 of 303 E. jordani,
51 of 1,102 P. vetulus, and a similar but larger flagellate in 9 of 35
L. exilis. After intraperitoneal injection flagellates from E. jordani
did not survive in P. vetulus, but did survive in other flatfishes;
flagellates from L. exilis survived in P. vetulus, but not E. jordani,
indicating the possible presence of two species, one in E. jordani and
one in P. vetulus and L. exilis.
A larger, sluggish cryptobiid was found in 134 of 1,102 P.
An extremely large cryptobiid, grossly different morphologically
from previously described species, was observed in 1 of 5
Scorpaenichthys marmoratus. The developmental cycle in the leech
vector Malmiana sp. was described; the leech Trachelobdella sp. was
also shown to be a potential vector.
Leeches belonging to the following genera were collected during
this study: Johanssonia, two species; Malmiana, three species;
Trachelobdella, Oceanobdella, Orientobdella, and Ostreobdella. Of
these, one species of Malmiana and one of Orientobdella were experimentally
shown to be vectors of hemoflagellates.