A rotkeil severum wears a red to orange wedge from the nape down over the shoulder and gill cover, on a gold to olive body. Shops sell it as red shoulder, red head or red neck severum. Juveniles ship plain, and the red comes in between 2 and 4 in (5 and 10 cm), first as spots behind the gills. It is one of the calmer severums and does well in a group or with Geophagus, larger tetras and plecos. It grazes soft plants harder than most, so stick to anubias and Java fern. Care is otherwise the species' care, with the same tank, water and food.
In the wild
Rotkeil is German for red wedge, after the patch of color behind the head. The fish is exported out of Peru, from the upper Amazon around Iquitos, and Aqua Imports lists its locality as the Rio Nanay. No collection point has been published. Keepers with contacts at the Iquitos exporters say much of the stock is raised in ponds there. Some keepers hold that it is a wild fish, and others that a cross with Heros severus produced it. Nobody has described it, so the trade files it under Heros efasciatus or sells it as Heros sp. Rotkeil.
Good to know
A true rotkeil carries eight dark bars, the first through the eye and the last on the tail base. Heros efasciatus and Heros notatus carry nine. A red-headed fish with nine bars is a mislabeled green or a hybrid, since rotkeils spawn readily with other severums. Imperial Tropicals sells a nine-barred red shoulder line beside its rotkeil and says it was likely crossed with efasciatus. Eschmeyer's Catalog of Fishes lists five valid Heros species and no rotkeil, so the fish has no name of its own.
Did you know
Shops have sold the same fish as raspberry face, raspberry nose, rainbow severum, orange shoulder and red neck severum. Spanish-speaking keepers call it corbata roja, the red necktie, for the wedge that runs down under the throat.
Weekly picks
Tank mates
Rotkeil severum is a mostly peaceful, social species that keeps to the middle. These picks share a community profile with it, are safe together in both directions, and overlap on water type, temperature and pH.
Is a Rotkeil severum a different species from the Severum?
No. A Rotkeil severum is a variety of the Severum, Heros efasciatus, and it wants the same tank, water and food as the species.
Is a rotkeil severum a different species from the green severum?
Nobody has settled it. Hobby specialists treat the fish as an undescribed Heros from Peru, and it carries eight bars where a green carries nine. Eschmeyer's Catalog of Fishes lists no such species, so shops file it under Heros efasciatus or sell it as Heros sp. Rotkeil.
Why has my rotkeil severum not turned red?
Give it time. The red comes in as spots behind the gills and on the face. Some fish start at 2 in (5 cm) and others show nothing until past 4 in (10 cm). A fish with nine bars that never colors up is a mislabeled green or a hybrid.
What size tank does a Rotkeil severum need?
A Rotkeil severum needs at least 65 gal (245 L). It spends most of its time in the middle.
How big does a Rotkeil severum get?
An adult Rotkeil severum reaches about 11.8 in (30 cm).
11.8 in (30 cm)119 gal (450 L)75–82°F (24–28°C)
11.8 in (30 cm)58 gal (220 L)72–84°F (22–29°C)
7.9 in (20 cm)106 gal (400 L)75–82°F (24–28°C)
7.9 in (20 cm)75 gal (285 L)79–86°F (26–30°C)
11.8 in (30 cm)119 gal (450 L)77–86°F (25–30°C)
11.8 in (30 cm)74 gal (280 L)75–82°F (24–28°C)