Glass Catfish, also known as Ghost Catfish or Phantom Catfish, is a small Asian glass catfish species.
It’s often found in freshwater aquariums but was only fully understood in 2013 due to confusing taxonomy.
This fish is native to Thailand and lives in rivers that flow into the Gulf of Thailand and the Cardamom Mountains’ river basins.
There are unconfirmed sightings in Penang, Malaysia. Before 1989, people thought it was the same as another glass catfish called Kryptopterus bicirrhis, but they’re actually different species.
In 2013, researchers discovered that the common aquarium glass catfish is Kryptopterus vitreolus and not K. minor as previously believed.
The true K. minor species mainly lives in Borneo and rarely appears in aquariums.
Glass Catfish Interesting Facts
- Glass catfish was fully understood only in 2013 due to confusing taxonomy, and is native to Thailand with unconfirmed sightings in Malaysia.
- Previously mistaken for K. bicirrhis or K. minor, researchers identified the common aquarium species as Kryptopterus vitreolus in 2013.
- The transparent-bodied fish prefers slow-moving, tropical freshwater habitats between 6°N to 13°N latitude.
- Unique features like fewer anal fin rays (48 to 55) and specific measurements of snout length, eye diameter, and body depth help differentiate it from similar species.
Glass Catfish Habitat
Glass catfish is found in Asia. Specifically, it lives in peninsular and southeastern Thailand but not in central Thailand.
There’s a report that they might be in Penang, Malaysia too, but this needs confirmation.
These fish live in freshwater environments near the bottom (demersal) and prefer tropical climates between 6°N to 13°N latitude.
This fish prefers slow-moving or still waters with brown to black coloration.
Glass Catfish Physical Characteristics
Size: 2.6 inches (6.5 centimeters)
Glass catfish is a small fish, growing up to 2.6 inches (6.5 centimeters) in length.
It has a unique transparent body that sets it apart from most other Kryptopterus species, except for K. minor and K. piperatus.
This fish has 32 dorsal soft rays and between 48 to 55 anal soft rays on its fins. It also has 44 to 47 vertebrae in its spine.
What makes the glass catfish different from other groups like K. cryptopterus, K. limpok, and K. schilbeides is that it has fewer anal-fin rays (48 to 55 instead of 64 to 85).
You can differentiate glass catfish apart from the similar-looking species in the K. bicirrhis group by looking at the following features:
- Snout length: 29% to 35% of head length,
- Eye diameter: 28% to 34% of head length,
- Body depth at anus: 16% to 20% of body length,
- Depth of caudal peduncle (tail): 4% to 7% of body length,
- Long maxillary barbels reaching past the base of the first anal-fin ray,
- A noticeable dip in the dorsal profile near the head (nuchal concavity), and
- Between 14 and 18 gill rakers on the first gill arch.