Purple Broad-fronted Crab
The Purple Broad-fronted Crab has a northern tropical Australian distribution. It ranges from northern WA, across northern shores including the NT, to south-eastern Qld (WA,NT, QLD).Features:
The Purple Broad-fronted Crab is a sesarmid crab with a square shaped carapace and is very wide between the eyes. Its carapace sides are almost straight, but converge partly at the rear. It grows to a carapace width of 40 mm. Metopograpsus crabs are not hairy, or spined like other sesarmid crabs. Like other grapsid crabs, the last pair of legs is not flattened to suit a swimming lifestyle, but are adapted for running over mud, sand and rocks. The arm or merus of the third maxilliped mouthparts is broader than it is long. The male crab has larger chelae that the females do.
This is a spectacularly coloured shore crab with a black carapace covered with symmetrical grey to brown mottling. It has brownish coloured walking legs and mauve to purple chelae, merging to white on the fingertips.Ecology/Way of Life:
The Purple Broad-fronted Crab occurs under mangroves, often in soft sediment, near high tide levels, usually under rocks and logs.Interaction with Humans/Threats:
The Purple Broad-fronted Crab lives on many northern tropical shores that are remote from human habitation and therefore is probably safe from human activities.Other Comments:
Metopograpsus latifrons . Metope is the Greek word for an opening to fit a beam-end of a sculptured slab, while grapsus comes from the Latinised Middle English word graspen, from the root of grapian, to grope. Latifrons comes from a combination of two Latin words lati, meaning broad, while frons means front.Further Reading:
Davey, K. (1998) A Photographic Guide to Seashore Life of Australia. p.59, New Holland Press, Sydney.
Jones, D. & Morgan, G. (1994). A Field Guide to Crustaceans of Australian waters. p.189, Reed.
Sakai, T. (1976). Crabs of Japan and the Adjacent Seas. Kodansha Ltd. Tokyo.
Text, map & photograph by Keith Davey.Sponsorship welcomed:
Please Contact ABRS if you wish to discuss sponsoring this or other pages.