High Quality Content by WIKIPEDIA articles! Hemigrapsus estellinensis is a extinct species of crab, formerly endemic to the Texas Panhandle. It was discovered by Gordon C. Creel in 1962 and was probably already extinct before his description was published in 1964, after the Estelline Salt Springs where it lived were contained by the United States Army. H. estellinensis is closely related to species from the Pacific Ocean such as Hemigrapsus oregonensis, but lived 500 mi (800 km) inland in a hypersaline spring. It differed from its relatives by the pattern of spots on its back, and by the relative sizes of its limbs.