Anubias heterophylla

Anubias heterophylla, commonly known as Lance Leaf or Congo Anubias, is a highly appreciated species in the aquascaping community for its distinct morphology and hardiness. Its specific epithet, 'heterophylla,' means 'different-leaved,' alluding to the variation in leaf shape that can occur on a single plant, especially between its emersed and submersed forms. The leaves are typically lanceolate (lance-shaped), leathery, and a deep, rich green, providing a strong vertical element in an aquascape. Its significant height potential makes it an excellent choice for background compositions, where it can effectively hide equipment like heaters and filter intakes.

Proper planting is the single most critical factor for success with this species. As an epiphyte, its thick, creeping rhizome must remain exposed to the water column. Burying the rhizome in substrate will lead to rot. The preferred method is to attach the plant to hardscape (rock or driftwood) using cyanoacrylate super glue or thread until its strong, wiry roots take hold. While it does not feed through its roots from the substrate, it does absorb nutrients from the water column. Therefore, it benefits from a comprehensive liquid fertilizer, although its slow metabolism and low nutrient demand mean it can subsist in fish-only tanks with minimal supplementation.

The slow growth rate of Anubias heterophylla is a double-edged sword. It requires very little maintenance in terms of pruning, but this also makes it highly susceptible to algae growth on its leaves, particularly Green Spot Algae and Black Beard Algae. This issue is exacerbated by high-intensity lighting. To prevent this, it should be placed in low to medium light areas, perhaps shaded by other plants or larger pieces of hardscape. Its wide tolerance for water chemistry makes it adaptable to most community tanks, from soft, acidic water to hard, alkaline conditions. Propagation is straightforward: the rhizome can be cut into sections with a sterile blade, ensuring each new piece has at least 3-4 leaves and some roots. This allows hobbyists to easily multiply their stock over time.

Anubias heterophylla Engler is a robust, monocotyledonous flowering plant belonging to the family Araceae. This species is indigenous to the tropical regions of central Africa, including Cameroon, Equatorial Guinea, Gabon, and the Congo, where it functions as a rheophyte. In its natural habitat, it colonizes the splash zones of fast-flowing, shaded rivers and forest streams, anchoring itself to rocks and fallen logs with its powerful, adventitious roots. This amphibious nature allows it to thrive in both fully submersed and emersed conditions, making it suitable for aquariums, paludariums, and vivariums.

The plant's morphology is well-adapted to its environment. It features a thick, creeping rhizome from which petioles and roots emerge. The leaves are its most prominent feature, with a leathery texture that serves as a defense against herbivory and physical damage from water currents. The leaf blades are lanceolate to ovate-lanceolate, with a variable base that can range from cuneate to cordate or even sagittate. The specific epithet 'heterophylla' reflects this morphological plasticity. Its slow metabolism is characteristic of shade-adapted plants (sciophytes). This results in a low rate of photosynthesis, minimal oxygen production, and low demand for nutrients and CO2. While tolerant of a wide range of water parameters, its growth is opportunistic, responding favorably but not dependently on supplemental CO2 and water column fertilization.

Reproduction in an aquatic environment is almost exclusively vegetative, occurring through the fragmentation and branching of the rhizome. Sexual reproduction is rare in submersed aquarium conditions. When grown emersed, A. heterophylla can produce a characteristic Araceae inflorescence: a greenish-white spathe surrounding a spadix. From a conservation standpoint, the International Union for Conservation of Nature (IUCN) lists Anubias heterophylla as 'Least Concern' (LC), indicating that it is currently widespread and not facing significant threats to its survival in the wild. Its low nutrient uptake rate means it is not a primary species for nutrient export or bioload reduction in a planted aquarium ecosystem, but it contributes to the overall stability and biodiversity of the closed system.