Phyllolithodes papillosus Brandt, 1849 Common name(s): Heart crab, heart lithodid, papillid crab, flat spined triangle crab, spiny-leg lithode crab
Synonyms: Phyllolithodes bicornis, Petaloceras bellianus
Phylum Arthropoda  Subphylum Crustacea   Class Malacostraca     Subclass Eumalacostraca      Superorder Eucarida       Order Decapoda         Suborder Pleocyemata         Infraorder Anomura          Family Lithodidae
	Phyllolithodes papillosus subtidal from Sares Head.  About 5 cm carapace width.
	(Photo by: Dave Cowles, July 2000)

How to Distinguish from Similar Species: Rhinolithodes wosnessenskii also has a triangular carapace with a depression in the middle but the legs are covered with setae and sharp spines, its rostrum is not divided into two blunt lobes, and the carapace has no tubercles on the dorsal surface but has sharp spines along the margin.

Geographical Range: Dutch Harbor, Alaska to San Miguel Island, California

Depth Range: Subtidal to 183 m

Habitat: Around rocks in deep water, especially with currents.

Biology/Natural History: This species is not frequently encountered.  Captive individuals readily eat urchins.  May also eat sponges.  This species often shelters under the anemone Cribrinopsis fernaldi, especially after molting (photo) (photo).  Juveniles can (rarely) be found under intertidal rocks.

Genus Phyllolithodes is characterized by large abdominal plates with softer centers (photo)

References:

General References:
  Harbo, 1999
  Jensen, 1995
  Johnson and Snook, 1955
  Lamb and Hanby, 2005

Scientific Articles:

Several more views of the species.  Photo by Dave Cowles, July 2000.  Captured subtidally at Sares Head.

Phyllolithodea papillosus often takes refuge under the crimson anemone Cribrinopsis fernaldi.
Photo by Dave Cowles, July 2008

This view of the face shows the red eyes, the flattened scales, and the blunt dorsal and ventral lobes on the rostrum.

As in many Lithodid crabs, the abdomen is broad and sculptured.  The abdominal plates are softer in the middle.  Note also the long bristly setae on the chelae.

This female was carrying eggs. Photo by Dave Cowles, July 2018
 

Several views of an individual captured at 12 m depth on Sares Head, June 2020. Carapace width 7 cm, carapace length 6.5 cm including rostrum. Photos by Dave Cowles

Above: Dorsal view. Below: Ventral view

Above: Ventral view with chelae. Below: Lateral view

Lateral view of head and rostrum.