Matt Clarke on Aequidens patricki, a beautifully marked and rarely seen South American cichlid.
Common name: Patrick's cichlid
Scientific name: Aequidens patricki Kullander, 1984
Origin: This species is only known from a couple of river systems in Peru - the Rio Aguaytia and Rio Pachitea.
Size: Males can reach around 12cm/5", but females are a little smaller.
Diet: Should take most chunky foods.
Water: I've heard of these being kept in hard water without problems, but if you want to get them looking at their best, soft and slightly acidic water is best. I'd keep them warm at about 27-29C.
Aquarium: I've never kept patricki, but if it's anything like its close relatives in the Aequidens genus, it could get a little feisty as it matures. Most are pretty simple to keep, but should only be mixed with fish of equal size or larger who are capable of sticking up for themselves. Many of the similar-looking Aequidens can also be wife-beaters, so make sure you provide plenty of hiding places, or consider bringing the female into condition and then reintroducing the male to her tank using a divider.
Identification: According to Sven Kullander, who described it, A. patricki is a member of the "true acaras" group. A few other representatives such as diadema, tetramerus, metae and pallidus also enter the trade, but there are about another seven or eight rarer species, and several that haven't been described yet.
Notes: This species is named after Patrick de Rham, a Swiss fishkeeper who is perhaps best known for his work on Malagasy cichlids.
Availability: This Aequidens is very rarely seen in the aquarium trade. These ones were imported by Maidenhead Aquatics @ Iver. Captive bred fish are sometimes available from Europe, but they are normally wild caught.
Price: Expect to pay about twenty pounds each.