Original description as Pseudotropheus callainos:
- Stauffer, Jay Richard Jr. & E. Hert. 1992. "Pseudotropheus callainos, a new species of mbuna (Cichlidae), with analyses of changes associated with two intra-lacustrine transplantations in Lake Malawi, Africa". Ichthyological Explorations of Freshwaters. v. 3(n. 3), pp. 253-264 (crc01065) (abstract)
Conservation: Metriaclima callainos is evaluated by the international union for the conservation of nature in the iucn red list of threatened species as (VU) vulnerable (2006). Although the Cobalt Zebra has been collected for the ornamental fish trade since the early beginning of the Malawi cichlid hobby, sometimes at a rate of more than 20,000 zebra per year, there is no visible threat to its existence. None of the geographical variants seems to be at risk.