large shrimp has the multiarticulated carpus
on its second pereopod
and the long rostrum
characteristic of Pandalids. Its first antenna is only about
or slightly longer than its carapace
(including the rostrum).
Abdominal segment 3 is not compressed and does not have a median dorsal
ridge or mid-dorsal spine anterior to the posterior edge. The
has mid-dorsal spines only on the anterior half. The rostrum
does not have mid-dorsal spines on the distal half (though it does have
ventral spines), and it ends in three points (trifid).
segment 6 is about 3x as long as wide. Body color consists of
red dots over a translucent background, with darker red background on
base of antenna, pleopods,
side of sixth abdominal segment, and dorsal surface of uropods
Up to 12.3 cm long.
tridens Rathbun, 1902
Common name(s): Yellowleg pandalid
Pandalus montagui tridens
tridens from the
Sea of Okhotsk, NW Pacific.
|(Photo by: Andrey Gontchar
How to Distinguish from
platyceros has an abdominal segment less than
twice as long
as wide. P.
eous, P. jordani,
goniurus don't have the steeply ascending rostrum
with the three pointed (trifid) tip. They also have a medial
ridge on abdominal segment 3. This is the only pandalid
this area which has light bands on its legs but no stripes or spots on
side of Bering Sea and Sea of Okhotsk to Channel Islands off Santa
Rocky and muddy bottoms,
may be more common on rocky bottoms.
This species was early identified as P. montagui tridens,
Bering Sea variation of the Atlantic P. montagui.
the larvae differ in several reliable anatomic respects from those of P.
montagui and the adults are colored differently, leading P.
to be given full species status. Except for the difference in
and the fact that the rostrum
of P. montagui ends in 2 points and that of P.
in 3, the adults of these two species are almost indistinguishable. P.
tridens tends to have more rostral
spines but the counts overlap. P. tridens
also has shorter
dactyls than does P. montagui.
The isopod Bopyroides
hippolytes infests the gills of this species but
does not infest
montagui. It may also be parasitized by the
This species is a protandroushermaphrodite
(is a male first, then later becomes female). It appears to
from male to female at about 1 1/2 to 2 years old. In the
of Georgia females may be ovigerous
(carrying eggs) from late November to early April.
and Hanby, 2005
General Notes and
abundances, unusual behaviors:
This dorsal view is also by Andrey Gontchar. This individual,
which is the same as the one at the top of the page, is a mature
It was collected at about 300 m depth in the Sea of Okhotsk, near
Authors and Editors of Page:
Dave Cowles (2009): Created original page
CSS coding for page developed by Jonathan Cowles (2007)
Rosario Invertebrates web site provided courtesy of Walla