|General Notes and
abundances, unusual behaviors:
a well-developed, toothed rostrum.
None of the teeth are hinged (movable).
This species' tissue is normally nearly clear. As with many
the whitish tinge appearing in the tissue here only appears when
the animal is metabolically compromised and dead or nearing
Live shrimp run so fast and so constantly that it is almost
to get clear photos of small body parts.
Being decapods, shrimp such as Heptacarpus
sitchensis have 5 pairs of pereiopods
(walking legs). The 5 pairs can be easily
counted in this photo. Anterior to the walking legs are 3
which are legs specially modified for feeding.
In this species the 3rd pair of maxillipeds
is large; as long as the legs and more robust. The first pereiopod
yellow-tipped chela. The second pereiopod
is more slender and has a multiarticulatedcarpus.
3-5 are similar
to one another but in this species their dactyl
(tip) is bifid.
As with many shrimp, the 2nd pereiopod
is thinner and slightly longer than the other walking legs.
of the 2nd pereiopod,
here draped across the dissecting pin, has a series of constrictions
that divide it into seven articles. This type of structure is
Although Kozloff's key lists epipods
at the bases of several pereiopods
and the 3rd maxilliped,
Wicksten et al., state that this trait is quite variable.
Other references state that the epipods
are often very small and hard to see. This view centers on
(thin leg near middle). The 1st
and 3rd maxilliped
are to the right of it and the 3rd and 4th pereiopods
are to the left. None of the leg bases has an obvious epipod.
This view of the propodus
4 clearly shows the bifid
tip of the dactyl.
view of the carapace
shows that the species has no supraorbital
spine, which would be just above the
eye near the base of the rostrum.
It also shows that the rostrum
is slightly shorter than the postorbital carapace.
orbit is the slot in the carapace
to accommodate the eyestalk and is the official 'front' of the carapace
(not including the
The postorbital carapace
is measured from that slot at the base of the eye straight back to the
spine at the anteroventral
margin of the carapace,
seen here just below the base of the 2nd antenna.
margin of abdominal pleuron
4 (middle-right) of this species has a spine. Abdominal pleuron
5 (middle-left) has a similar spine. The third
segment (top right) of hippolytid shrimp is usually bent, leading to
family name of "broken-back shrimp".
view of the head shows that the anterior end of the basal segment of
has only one
prominent spine near where it articulates with the second segment.
view of a live individual shows the normally transparent or translucent
tissue, the pigmented oblique lines seen on the carapace
and illustrates how the colors can change (compare this view to those