Coral Red Pencilfish Care Guide
Nannostomus mortenthaleri · Freshwater Fish
What Coral Red Pencilfish look like
Nannostomus mortenthaleri, commonly known as the Coral Red Pencilfish, exhibits a diminutive and torpedo-shaped body, reaching a maximum adult size of approximately 1.5 inches (3.8 cm). The species is characterized by its vivid scarlet coloration, which is accentuated by bold black horizontal stripes that run along the length of its body, creating a striking contrast. This coloration serves as a form of aposematic signaling, warning potential predators of its unpalatability. The fish possesses a laterally compressed body, which aids in maneuverability within its natural habitat. Notable morphological features include a small, terminal mouth equipped with fine, comb-like teeth adapted for grazing on small food particles. The dorsal fin is positioned towards the rear of the body, while the anal fin is elongated, contributing to its streamlined appearance. The presence of an adipose fin further distinguishes this species within the Lebiasinidae family.
Behavior & temperament
In terms of behavior, Nannostomus mortenthaleri is a social species that thrives in small groups, often exhibiting a schooling behavior that enhances its safety in the wild. These fish are primarily pelagic, dwelling in the upper water column of slow-moving streams and rivers in their native South American habitat. During breeding, they exhibit egg-scattering behavior, where females release eggs into the water column, allowing fertilization to occur externally. The species is generally peaceful and exhibits low aggression levels, making it suitable for community tanks. However, they can be skittish and may require ample cover and plants to feel secure in their environment.
Diet & feeding
In the wild, the Coral Red Pencilfish is an omnivore, feeding on small invertebrates, zooplankton, and plant matter. In captivity, they thrive on a varied diet that includes high-quality flake food, micro-pellets, and live or frozen foods such as brine shrimp and daphnia to ensure optimal health and coloration.
Behind the name
The genus name 'Nannostomus' derives from the Greek 'nanno' (dwarf) and 'stoma' (mouth), indicating the small mouth size, while the species name 'mortenthaleri' honors the ichthyologist who contributed to the study of this group.
Plan your tank
Check the numbers before you buy: tank volume, a stocking plan, cycle progress, water changes, and your ongoing care routine.
Keeping Coral Red Pencilfish?
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