Tire Track Eel

Distribution:
   The Tire Track Eel was described by Hora in 1924. They are found in Southeast Asia including India, Myanmar, Thailand and the entire Malay Peninsula where they inhabit moving waters. They often bury themselves during the day in the gravel substrate, coming out at night to feed on insects larvae, worms, and vegetation.

Status:
   The species is not listed on the IUCN Red List.

Description:
   The body of the Tire Track Eel is elongated with a long snout. Both the dorsal and anal fins are extended and joined to the caudal fin. Its background coloration is a tan to light brown.
   Along the entire length of its body, reaching vertically from its back to its belly, it is patterned with a series of irregular dark markings. These markings have a 'tire track' or 'zig zag' appearance which has been used as a common name for this fish as well as several other species of spiny eel.

Size - Weight:
   These fish will generally as long as 28 inches (70 cm), though some have been reported to reach up to 36 inches (91 cm).

Care and feeding:
   The Tire Track Eels are primarily carnivores. Like all spiny eels they prefer a diet of live and fresh frozen foods such as brine shrimp, black worms, earthworms or bloodworms. Some Tire Track Eels can be trained to eat freeze dried brine shrimp or bloodworms but this is not something that can be counted on. They will also eat small fishes so make sure their tank mates are too large to be able to fit into their mouths.
   If their tank has a sand or fine gravel substrate, they may burrow into it. Make sure they have plenty of hiding places so they will feel secure in their new home. This species of spiny eel can eventually grow to be quite large so plan accordingly. That cute little 4 inch fish may eventually grow to over 2 feet long! Keep small specimens up to 6 inches in a tank that is at least 36 inches long and about 35 gallons. Larger specimens will needing an even bigger area, tanks that are 48 inches in length or longer and 55 gallons and up will be necessary. Provide a tight fitting lid as spiny eels are escape artists. These fish respond poorly to copper based medications, so these should be avoided.

Water Region: Top, Middle, Bottom:
   Tire Track Eels will spend most of their time on the bottom of the aquarium.

Acceptable Water Conditions:
   Temp: 74 - 82° F (23 - 28° C)
   pH: 7.0 - 8.0

Social Behaviors:
   They are a nocturnal species but are generally peaceful and shy. They mostly ignore other tankmates although they may eat fish that are small enough to fit into their mouths. Some species of spiny eels can get territorial and aggressive with their own kind so a general rule of thumb is to keep them singly unless you plan to breed.

Sexual Differences:
   Sexual differences are unknown and it is almost impossible to identify the sexes, though a mature female may be more full bodied.

Breeding/Reproduction:
   The Tire Track Eel has not been bred in captivity. Only a few spiny eels have been bred in the aquarium, possibly because they are generally kept singly rather than in a group where a male and female can find each other. Though it is not documented what makes them spawn, trying to emulate the bounty of the flood season can help stimulate breeding behavior. Feed more and higher quality food than you normally would and providing an influx of clean water. Their courtship lasts for several hours, where they chase each other and swim in circles.
   The eggs are deposited among floating plants. They are sticky so will adhere to the plants and then hatch in 3 to 4 days. The fry becoming free swimming a few more days after that and should be fed nauplii. The fry are something of a challenge to raise as they are susceptible to fungal infections. Regular water changes and the use of an antifungal water treatment can help.

Availability:
   The Tire Track Eel is commonly available and reasonably priced. Be aware when purchasing that the Tire Track Eel is often misidentified in its common name as the Zig Zag Eel Mastacembelus armatus. As these two similar looking eels attain a much different adult size it is important to know which eel you are purchasing. The Tire Track Eel can grow to about 28" in length while the Zig Zag Eel can reach up to 36".

Author: Clarice Brough, CFS