{       

     

Coenobita rugosus

中文/日本語

Click different parts of the land hermit crab

Scientific name: Coenobita rugosus
Chinese name: 灰白陸寄居蟹 / 皺紋陸寄居蟹 / 波紋陸寄居蟹 / 哭陸寄居蟹
English name: Wrinkled Land Hermit Crab / Crying Land Hermit Crab
Japanese name: ナキオカヤドカリ
Max length of front part (head) of  cephalothorax: 15mm
Distribution(Map):

India ~ Pacific Ocean, Eastern part of Africa, Philippines, Malaysia, Japan, China, Taiwan, Ryukyu Islands, Polynesia

Habitat::

Live in the forest which near the beach.

Chirping: can make sound
Favorite Shell: Neritidae, Turbo shell, Lunella coronata, Bufonaria
*Remark

most common species

The following species information  is for reference only

 Body Colour / Spot
 

C. rugosus have various body colour, can be form light to dark. For example, Gray, Gray-brown, Gray-green, reddish orange, white, pink, yellow, sandy, black or red etc. This various colour make us very difficult to identify them especially when they are juvenile.

Sometime C. rugosus may also be purple in colour, it is easily to be misunderstood as C.purpureus.

There are many light colour granule / spot on the body.
 

 

Black diagnol (/) (Red circle) stripe behind the bases of the outer antennae's, on the side of the body. Harder to see on darker one's.
 

 

There is a weird markings (Red circle) on their backjust like /()\ .
 

 

 


↑TOP

 Eyes / Eyestalks
 

Eyes are elongated in shape. Eyestalks are white / sandy in colour. There is some black-brown stripes on the eyestalks (Red circle). Black-brown stripes will appear after they landing 1~2 years.

 


↑TOP

 Antenna
 
The bottom part of 2nd pair of antenna (Red circle) are light orange or light yellow in colour. Antennal acicle cannot move, fused with second segment of its peduncle.
 

 


↑TOP

 Claws / Walking Legs
 

Left claw is larger than right claw. There are 7 ridge (////) on the upper part of the big claw (Red circle). There are some hair on the inside part of both claws.

Palm of big claw as four-cornered in an external form (red rectangle).

 

Shape of big claw has a little bit different among different species

 

Shape of big claw of p.purpureus and c.rugosus has a little bit different.

(But there may be some exceptional case)

 


The last 2 part of their 3rd left Walking legs is flatten (Red circle) and the colour of these 2 parts is lighter then other part (White circle).

 

According to the articles of Akira Asakura (Japan Natural History Museum and Institute, CHiba) and Yukio Nakasone (University of the Ryukyus), outer surface of propodus of left 3rd leg separated from dorsal surface by a well-marked longitudinal crest.

 DRAW by TONY

 


↑TOP

 Abdomen
 

Abdomen is quite short and fat (Red circle).

 


↑TOP

 Male sexual tube
 

The shape of male sexual tube as below.

 


↑TOP

C. cavipes C. brevimanus C. perlatus
C. rugosus C. purpureus C. violascens
C. clypeatus C. variabilis C. compressus
C. spinosus C. scaevola C. olivieri
C. carnescens C. pseudorugosus C. rubescens
C. longitarsis Birgus latro

 

1