Brown Pencilfish, also known as Diptail Pencilfish, or Nannostomus eques, is a small freshwater fish that belongs to the Lebiasinidae family.
Its name comes from Greek and Latin words meaning “small mouth” and “horseman.”
Brown Pencilfish was first described in 1876 by Franz Steindachner, making it one of the earliest members of its genus to be discovered.
Brown Pencilfish is highly sought after in the aquarium trade due to its distinctive upward-pointing snout, a unique trait shared only with another species in its genus, Nannostomus unifasciatus.
This fish feed on eats worms, crustaceans, and insects.
The minimum tank size for this fish is 60 centimeters (about 24 inches), and it’s best to keep them in groups of at least five in an aquarium.
Brown Pencilfish Interesting Facts
- Brown Pencilfish swim with their snout pointing upward, a unique feature in its genus.
- These fish are found in South American countries like Brazil, Peru, and Colombia.
- Their diet includes worms, crustaceans, and insects.
- They thrive in the pH range of 5.0 to 6.0 and temperatures between 73.4°F to 82.4°F (23°C to 28°C).
Brown Pencilfish Habitat
Brown Pencilfish is a type of fish found in South America, specifically in the central and upper Amazon region.
It can be found in various South American countries like Brazil, Peru, Colombia, and Guyana.
Brown Pencilfish lives in freshwater environments and prefers to swim near the bottom of the water (benthopelagic).
The ideal water conditions for this fish include a pH range between 5.0 to 6.0, a dH (water hardness) range from 5 to 12, and temperatures between 73.4°F to 82.4°F (23°C to 28°C).
It thrives best under these specific tropical conditions.
| Water Temperature: | 73.4°F to 82.4°F (23°C to 28°C) |
| Water pH: | 5.0 to 6.0 pH |
| Water Hardness: | 5 to 12 dH |
Brown Pencilfish Physical Characteristics
Size: 2 inches (5.0 centimeters)
Brown Pencilfish reach up to 2 inches (5.0 centimeters) upon maturation.
It has an elongated body with noticeable horizontal stripes, which is typical for its genus.
Brown Pencilfish Reproduction
Brown Pencilfish are oviparous, meaning they lay eggs to reproduce.
Brown Pencilfish Scientific Classification
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Actinopterygii |
| Order: | Characiformes |
| Family: | Lebiasinidae |
| Genus: | Nannostomus |
| Scientific Name: | Nannostomus eques |
| Also Known As: | Brown Pencilfish, Diptail Pencilfish |
| Conservation Status: | Unknown |