Zamioculcas zamiifolia 'Oscura'
Native range: Eastern Africa
Known names: ZZ Plant, Zuzu Plant, Emerald Palm, Zanzibar Gem
Hardiness: Avoid freezing temperatures
Mature Size: ~3' Tall, ~3' Wide
Light: Will tolerate dark rooms, best in a well-lit room. 
Water: Drought tolerant, water when soil is dry.
Soil: Succulent mix, standard potting mix
Dormancy Period: N/A
Pet-Safe: No
Plant Size: 4" pot, shipped semi bare root
 
'Oscura' produces dark dark dark green leaves, usually emerging green then darkens over time.
One of the very few plant that we would recommend for a darker room. Thick, waxy. eliptic leaves on upright (that resembles a cycad) stem that can extend to close to 4'. Potato-like tubers form under the soil line with thick roots. Slowly expands outward.