Pseudacanthicus sp. “L273”

Order: Siluriformes
Suborder: Loricarioidei
Family: Loricariidae
Subfamily: Hypostominae
Genus: Pseudacanthicus
Species: not described yet

Pseudacanthicus sp. "L273"  is a large growing pleco. It can reach sizes of  40 cm. Most specimens in captivity stay around 30 - 35 cm body length. The whole body is covered with hard spikes, which can cause bleeding wounds when touched with the bare hands. This fish shows big fins and an overall strong body. On the tips of the caudal fin it can show long filaments.

Its ground coloration is in most cases olive green but can also show a more brownish, beige or grey coloration or almost black. In general the ground coloration is brighter in the head region and gets darker the further it goes back to the tail. Om top of it  a pattern off black spots can be seen, which start from the shoulders and get more numerous till the back of the body. In between those black patches, yellow/orange/salmon red or golden patches can be seen, depending on the specimen. The fins of this beautiful pleco can show a bright orange to red coloration with black spots in it. Mostly the dorsal- and caudal fin show this orange color. On the dorsal fin mostly only the tip is orange colored, the caudal fin shows mostly a orange seam.

This fish can show a territorial behaviour towards its own kind and other big plecos. In general this fish is very light sensitive and hides mostly in a cave over the day. In nature, this species can be found in deep water around 20 - 25 meters. When its dark, "L273" searches active for food. With its big fins, this pleco is a good swimmer and needs therefore a lot of space.

This fish appears in different color forms. Depending on the color form it is traded under names like "Yellow Titanic", "Red Titanic" or "Red Salmon Titanic".

Pseudacanthicus sp. "L273" is found in the Rio Tapajós in Brazil. In deep waters of around 20 meters depth this fish is mostly catched. The water there is rich in oxygen and slightly acidic (6 - 6,5 pH). This fish likes it warm, temperatures of up to 30 °C can be measured in its habitat.

Even though this species sometimes takes plant matter its main diet consists of animal proteins. In nature "L273" mostly eats dead fish, crustaceans, worms and insects (larvae).

In captivity this fish can be fed with frozen, live and dried food. Protein rich granules are a good base food for P. sp. "L273". Additional frozen shrimps, mussels, krill and artemia can be fed. Sometimes its necessary to feed this fish shortly before the lights go out. Even though its a big pleco, he tends to be shy and prefers to eat when its dark. Most "L273" get used to feeding during the day light though.

As previously mentioned, this fish gets huge and therefore needs a lot of space when grown out. Most "L273" in the trade are small enough for normal home aquariums. Since "L273" is a slow grower, it takes several years to reach sizes over 30 cm. Adults shouldn't be kept in tanks under 200 cm length. This fish swims a lot during night, even though it seems a bit inactive over the day.

Very important is a good lid for the aquarium, since Pseudacanthicus spp. push themselves sometimes far above the water surface. Uncalm behaviour can often be observed when the pleco has gill worms. This leads the fish to jump, swim fast or reach for air outside of the water.

The water should be heated up to 26 - 30 °C and kept neutral to slightly acidic. Good ventilation with an air stone and a good filtration are necessary to keep the fish healthy.

Depending on how many other plecos are in the tank, it should be structured well, to avoid to many territory conflicts. Pseudacanthicus stay mostly calmer in over-crowded tanks.  An over-crowded tank is only possible when there is a big and efficient filter installed, that can deal with the massive load of bio mass. Meat eaters produce a lot of ammonia, which can be lethal in to high doses.

Structure can be created with different big caves, driftwood and big rocks. Everything should be installed in a way that the "L273" can't toss it over or falls when being digged under. This species digs a lot and enjoys therefore a lot of substrate like sand or gravel.

Light is not necessary. Dimmed light helps to see this shy fish more often over the day.

With this page we want to explain the differences in male and female of probably one of the most colorful and variable colored Pseudacanthicus species.

From the side view we can see, that the male appears to be way more bulkier and robust built than the female. This trait that gets more visible, the older the fish get. It is not visible on the picture but the male is almost double the size of the female, which makes sexing the male of course easier than the female. Nonetheless are females with around 25 cm already adult and are able to breed, they just can still grow up to 40 cm in size!

When we look closer to the head, we can see that the tip of the females head ends pointier. The males head seems way more robust and in that specimen even has a slight convex curvature.

Odontodes on the snout, the gills and the pectorals are mostly more numerous and longer with males, but as always, take care with sexing Pseudacanthicus spp. solely on the odontode growth. They can vary depending on the dominance, breeding mood, and individual traits.

The hard ray of the pectorals are thicker and more pronounced with males.

The odontodes on the sides of the body are visible in both sexes and are also not a good sexing indicator with this species.

Differentiating male and female from top seems to be the most common way in the hobby. A round silhouette is more common in gravid females but as we can see in the picture, also fat males can show a rather round body line. The main difference we can see here is the head to body ratio. Males develop a way bigger and broader head than females and are more robust till the tail, where females mostly end pointier and slimmer. Also good visible from top are the differences of the pectoral fins in both sexes. The male shows really strong and broad hard rays in the pectorals.

If we take a closer look to the head of the male, we can again see the more pronounced odontodes on the outside border of the head. Also good visible is the more rounded tip of the head of the male in comparison to the pointy head of the female.

The shape of the papilla itself, is mostly not a good sexing indicator with this genus. It contracts a lot and changes therefore the shape constantly. Also depending on the mood, more or less of it is visible outside of the body. Its maybe a bit hard to see on this particular picture, but when zoomed into to it, the female shows yellow spots in the genital area, which are not visible at the male.

A lot of times Pseudacanthicus spp. get also sexed over the intensity of the coloration. While in most cases males tend to be more colorful and contrasty, "L273" tends to be to variable in coloration to show a strict sexual dichromatism.

Pseudacanthicus pitanga "L273" is a cave breeder. The male protects the egg batch till the fry hatch and eat up their yolk sacc.

In captivity this pleco gets rarely bred. It is hard to find harmonizing pairs, which are not to aggressive towards each other. Also tunneling occurs really late and short before laying eggs. It is said, that reported spawns were connected to bigger changes in air pressure and weather. A lot of water changes with soft water and high temperatures can trigger this species to mate.

Raising of the fry is really difficult with this species. Already after a few days it is better to separate the babies in groups of maximaal 10 - 20 pieces in big breeding boxes. The babies sometimes harm each other which leads to death or to crippled growth. This results mostly in short heads, twisted bodies and miss formed fins. Also the youngsters need a lot of fresh water and a lot of oxygen. Protein rich food is a key element in raising and breeding this species.