Grapsus longitarsis

Grapsus longitarsis
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Clade:	Pancrustacea
Class:	Malacostraca
Order:	Decapoda
Suborder:	Pleocyemata
Infraorder:	Brachyura
Family:	Grapsidae
Genus:	Grapsus
Species:	G. longitarsis
Binomial name
Grapsus longitarsis Dana, 1851

Grapsus longitarsis, also known as the long-legged rock crab, is a species of shore crab in the family Grapsidae.¹ It was first described in 1851 by the American zoologist James Dwight Dana.² This species occurs throughout the tropical Indo-Pacific,³ including Hawai'i, Tuamotu Archipelago, the Cook Islands, and has been recorded in regions such as Indonesia,⁴ and the coast of Somalia.³

Grapsus longitarsis is a medium-sized crab with an adult carapace width of approximately 32–33 mm and a length of 25–29 mm.¹ The species is physically distinguished from others in its genus by having lateral margins of the carapace that are nearly straight.² The body coloration is typically pale yellow and is often marked with small reddish-brown spots.⁴ Its walking legs are notably elongated, which is a key characteristic of the species.³ The fingers of the claws are darker in color and feature "spooned" tips used for feeding.⁴

Grapsus longitarsis is widely distributed throughout the tropical Indo-Pacific region.³ The species is native to several island chains, including Hawai'i, Tuamotu Archipelago, and the Cook Islands.⁴ It is also commonly found in the waters around Indonesia.⁴ Records of the species extend as far west as the coast of Somalia in the Indian Ocean.³ This crab typically inhabits high-energy coastal environments, such as wave-exposed rocky shorelines.¹ It is a benthic species usually found in the intertidal zone at depths of 0-5 meters.⁵ During low tide, the crab is often observed within tidal pools.⁴