Pagurus caurinus Hart, 1971
Common name(s): Greenmark
hermit
|
Synonyms:
Pagurus setosus |
|
Phylum Arthropoda
Subphylum Crustacea
Class Malacostraca
Subclass Eumalacostraca
Superorder Eucarida
Order Decapoda
Suborder Pleocyemata
Infraorder
Anomura
Superfamily Paguroidea
Family
Paguridae |
Pagurus caurinus (underwater) |
(Photo by: Aaron
Baldwin) |
Description:
The carapace
of this small hermit crab is smooth (without dorsal spines), the
lateral
parts are covered with soft setae, and only part of it is
calcified.
Eyescales
have no deep median furrow, and their base is not covered by the carapace.
Leg 4 is subchelate.
Abdomen
coiled, right cheliped
is nearly as long as the walking legs and its carpus
is longer than wide. The left cheliped
is smaller than right but similar in structure. Both chelipeds
are greenish-brown and gray, often with orange tips. The merus
of both chelipeds
is brown and gray with a dull white or yellowish distal band.
The
merus
of the chelipeds
often have orange-tipped spines. Dactyls
of legs 2-3 not twisted. The carpus
of the right (but not left) second pereopod
(first walking leg) is serrated. Dorsal
surface of propodus
of left chela
with neither a prominent ridge or crest nor a concavity. Ventral
surface of merus
of right cheliped
with 1or 2 prominent tubercles.
Chelae
with irregular rows of stout spines along with long tufted setae.
Antenna 2 reddish brown without white spots. Has a white band
at
the articulation of dactyl
and propodus
on legs 2 & 3. Carapace
length to 1 cm. Carapace
is light gray and cream with lengthwise purple stripes, each of which
has
light dots. The abdomen
is purple and gray.
How to Distinguish
from Similar Species: P.
hirsutiusculus also has 1 prominent tubercle
on the ventral
surface of the merus
of the right cheliped
and white (or bluish) bands between the propodus
and dactyl
on legs 2-3 but the tubercle
is often obscure plus the chelae
have closely spaced tubercles
& granules instead of spines. Its second antennae are
green with
white spots. Pagurus hemphilli has
orange-red antenna 2 and
no white band between the propodus
and dactyl
of legs 2-3.
Geographical Range:
Port Gravina,
Alaska to Los Angeles (rare in California)
Depth Range:
Mostly subtidal to 126
m, occasionally intertidal in cold waters on outer coast.
Habitat: Rocky
or sandy, exposed or sheltered
Biology/Natural
History: This species
is common in the Puget Sound region but most are so small they are
assumed
to be juveniles of other species such as P.
hirsutiusculus.
References:
Dichotomous Keys:
Coffin,
1952 (as P. setosus)
Hart,
1982
Kozloff
1987, 1996
Wicksten,
2009
General References:
Jensen,
1995
Scientific
Articles:
Web sites:
General Notes and
Observations: Locations, abundances,
unusual behaviors:
Authors and Editors of Page:
Dave Cowles (2006): Created original page
|