This plant is sourced from Tropica Aquarium plants.  Here is the description of this plant from Tropica:

The appearance of Littorella Uniflora makes it an easily recognizable plant in the aquarium.

It grows wild on lakeshores of Europe, North America, and South America. Tolerates quite low light intensity, but this will add to the length of leaves.

Each rosette is planted separately at a distance of a few cm.  They will readily send out runners. In time a very characteristic carpet of fat and fleshy leaves – each 2-5 cm long and 0,1-0,3 cm wide – will be created. Be careful when maintaining the tank, the leaves are easily damaged.

Littorella Uniflora is suitable for terrariums and garden ponds, too.

INSTRUCTION:

• Type: Stolon
• Origin: Cosmopolitan
• Growth Rate: Slow
• Height: 3-5+ cm
• Light Demand: Low
• CO2: Low

Attention! Please read the following important notes before ordering any live plants:

For all customers outside of California, please do not order plants via UPS Ground shipping or USPS first class mail, there is a very high chance they will not make it alive.  No live arrival guarantee for USPS first class, UPS ground, and FedEx ground.  USPS priority mail is guaranteed with a 50% refund/credit.  Although USPS priority mail is the most popular and ships fine in most cases, occasionally it could get mishandled or delayed, so please order at your own risk.

*Please refer to the link here for more details of our Live plants guarantee policy before you make the purchase.

Due to the fact that live plants are highly perishable, we strongly recommend the purchase of a thermal bag and cold pack set ($5 each) with each plant order value under $50 (not including shipping).

We will include the thermal bag and cold pack set for FREE if each plant order exceeds $50 (not including shipping).