Anubias hastifolia

Anubias hastifolia, often sold as the Spear Leaf or Hastate-leafed Anubias, is a robust and visually distinct member of the Araceae family. Its most notable feature is its leaf morphology; the dark green, leathery leaf blades (lamina) are hastate, or spear-shaped, with pronounced basal lobes that point outwards. These leaves sit atop long, slender petioles that can extend significantly, contributing to the plant's impressive total height and making it an ideal background specimen.

This plant is a rhizomatous epiphyte, meaning it grows from a thick, creeping rhizome that stores nutrients and anchors the plant to hard surfaces. A critical aspect of its care is ensuring this rhizome is never buried in the substrate, as this will lead to anaerobic conditions and fatal rot. Successful cultivation involves attaching the rhizome to driftwood or porous rock using cyanoacrylate super glue gel or thread. The roots will eventually envelop the hardscape, creating a naturalistic appearance.

Its growth rate is exceptionally slow, a common trait among Anubias species. This slow growth makes it highly susceptible to algae, particularly Black Beard Algae (BBA) or Green Spot Algae, if placed under direct, high-intensity lighting. To mitigate this, it's best positioned in areas of low to medium light or shaded by taller, faster-growing stem plants or floating flora. While it does not require CO2 injection, a stable environment with a comprehensive liquid fertilizer will encourage healthier, more robust growth and prevent nutrient deficiencies, which can manifest as yellowing leaves (chlorosis). Because of its low nutrient uptake, it does not contribute significantly to nitrate and phosphate reduction in the water column.

Propagation is straightforward for the patient hobbyist. It is achieved by vegetative division of the rhizome. Using a sharp, sterile blade, the rhizome can be cut into sections, ensuring each piece has at least 3-4 healthy leaves and a solid portion of the rhizome to support new growth. These new cuttings can then be attached to hardscape elsewhere in the aquarium. Occasionally, under stable conditions, Anubias hastifolia may produce a flower underwater—a creamy-white spadix surrounded by a greenish spathe—which is a fascinating event for any aquarist to witness.

Anubias hastifolia is a species of flowering plant in the aroid family, Araceae, native to West Africa, with known populations in Ghana, Nigeria, Cameroon, and the Democratic Republic of Congo. Taxonomically, it belongs to the Alismatales order, a group of monocots that contains a large number of aquatic and wetland plants. The genus name, Anubias, is a reference to the Egyptian god of the afterlife, Anubis, alluding to the plant's preference for shaded, dimly lit habitats along forested riverbanks and streams. Its IUCN Red List status as 'Least Concern' (LC) reflects its widespread distribution and stable populations in its natural range.

Morphologically, the species is characterized by its thick, creeping rhizome, typically 1-1.5 cm in diameter. The petioles are notably long, often reaching 30-50 cm, and are generally much longer than the lamina. The leaf blade (lamina) is the most distinguishing feature, exhibiting a hastate to sagittate shape, measuring up to 30 cm long and 14 cm wide. The posterior lobes of the leaf are well-defined and often spread outwards. The plant's cellular structure results in tough, coriaceous (leathery) leaves, which serves as a physiological adaptation to deter herbivory and withstand mechanical stress from water currents in its rheophytic habitat. This species exhibits phenotypic plasticity, with leaf morphology varying based on environmental factors such as light intensity and whether it is growing in an emersed or submersed state.

Reproduction in situ occurs both sexually and vegetatively. The inflorescence, typical of Araceae, consists of a spathe and spadix. The spathe is a small, greenish, ovate structure that opens to reveal the spadix, where the male and female flowers are located. In its natural habitat, it often grows emersed or semi-emersed, allowing for pollination. Vegetative propagation occurs naturally through rhizome fragmentation. Its metabolic rate is very low, corresponding to its slow growth, a k-strategy adaptation to stable, low-light, and often nutrient-limited environments. This low metabolic demand explains why it does not require supplemental CO2 or high nutrient loads in an aquarium setting, as it is adapted to efficiently utilize available resources.