Small Hyocrinus species with stalk length to 120 mm; aboral cup with ribbed ornamentation usually present; arms ... [details]
Very large Hyocrinus species with stalk ~1 m long.; tegmen well developed and inflated; aboral cup with broad ... [details]
Central eastern Pacific Ocean WSW of Cabo San Lucas, Mexico; 4300-4700 m. [details]
Horizon Seamount, N Pacific Ocean; ~1830 m. [details]