Microcarpaea Minima Merrill TC – IC299

Microcarpaea minima is a small, fragile wetland plant that may grow both above and below water and is native to Southeast Asia, Japan, and northern Australia. It can be found in and around shallow, warm, periodic bodies of water like puddles and rice fields, as well as on riverbanks.

It is the only member of the genus Microcarpaea, and it is related to Glossostigma (Phrymaceae). Wim Tomey (Netherlands) was the first to introduce it as an aquarium plant from West Kalimantan, and it is still a rarity in the aquarium hobby. Microcarpaea minima Merrill is the species name in the ADA tissue culture line; the last part is the author citation of the species name.

This plantlet grows as low cushions with 3-5 cm long, narrow leaves and little pale purple flowers on slender stalks in its terrestrial form. With up to 20 mm length and 1-2 mm wide leaves, the submerged stems grow straight, branching, and a little chaotic in all directions.

This plant is not difficult to cultivate, although it does benefit from bright lighting, soft to medium-hard water, and CO₂ supplementation. Because it is thermophilic, the temperature should be much above 20 degrees Celsius. Planting the fragile stems might be a little tricky, so tweezers are recommended. Trimming the spreading, developing shrubs will keep them at a manageable height.

Aquascapers may be unfamiliar with Microcarpaea minima. It looks great in small tanks as a low, light green bush or little carpet in the foreground or middle ground. It stands out among the foreground plants with its tiny, almost needle-like leaves. Its cushion-like terrestrial form could be useful in emersed setups, where its tiny flowers and fruit capsules could be expected.

Care Tips

• Benefits from bright lighting, soft to medium-hard water, and CO₂ supplementation
• Use  tweezers to plant it as its very fragile.