Guyana’s coast isn’t only about seawalls, koker stories, and mangrove restoration. Beneath those same mangrove roots lives a tough, spotted, armour-plated catfish that most people have never heard of but that scientists have been writing about since the 1800s: Hypostomus watwata.
The Hypostomus Watwata. [Photo credit: Maël Lemaitre]
WHAT IS HYPOSTOMUS WATWATA?
Hypostomus watwata is a large, plate-covered catfish in the Loricariidae family, the same family as the popular aquarium plecos.
Unlike many of its relatives that stay far upriver, this species is tied to the coast. It was described as early as 1828 and is recorded for coastal drainages from the Oyapock River (on the French Guiana–Brazil border) right across the Guianas, including Guyana’s Demerara system.
In simple terms: if you are near the lower Demerara, Mahaica, Mahaicony or any short, muddy coastal creek with mangroves, this is the kind of catfish you can expect to find.
A CATFISH THAT LIKES MANGROVES
Most plecos like clean freshwater. Hypostomus watwata is different. It is repeatedly reported from brackish, mangrove-influenced creeks and estuaries.
That fits Guyana perfectly, because our coast is lined with red, black and white mangroves that trap mud and organic matter. Mangroves create slow, shaded water. That’s exactly where this fish feeds.
The Hypostomus watwata. [Photo credit: Guyana Wild Fish]
SIZE AND APPEARANCE
- Grows to about 45 cm (standard length) — so, a large creek fish.
- Body covered with bony plates (armoured).
- Dark body with distinct dark spots, sometimes extending onto the belly — a key trait to tell it from other Hypostomus in the Guianas.
- Suckermouth on the underside, allowing it to cling to roots, wood and even burrow walls.
HABITAT IN GUYANA
In Guyana, the best place to look for Hypostomus watwata is the lower, tidal part of rivers, such as the Demerara, Mahaica, Mahaicony, and other short coastal systems, especially where mangroves line the banks.
It favours soft, muddy banks, shaded water and areas with some salinity, though it is still a freshwater fish. This is a reminder that our short coastal rivers, which are often treated as drainage canals, actually support specialised native species.
FEEDING: THE MANGROVE VACUUM CLEANER
Diet studies on closely related Hypostomus species show a lot of detritus, algae, diatoms and plant fragments, basically whatever is growing on and breaking down around mangrove roots. That makes H. watwata part of the coastal ‘clean‑up crew,’ quietly processing organic matter and keeping surfaces from being overgrown.
Mud-bank burrowing and spawning
One of the most interesting things about Hypostomus watwata is its breeding strategy. It digs burrows in soft mud banks, lays its eggs inside and guards them. That makes intact mangrove and creek banks very important.
If we cut mangrove roots, harden the banks, or dump spoil that collapses the mud, we remove the very places where this fish reproduces. This is a direct link between mangrove protection and fish conservation on the coast.
AIR-BREATHING ABILITY
The species is believed to be a facultative air breather, meaning that in warm, low‑oxygen, muddy water, it can gulp air to supplement its oxygen intake. That is a perfect adaptation for Guyana’s tidal creeks, especially in the dry season or in blocked channels.
References
- https://www.fishbase.se/Country/CountrySpeciesSummary.php?c_code=254&id=49355&utm_
- https://repository.naturalis.nl/pub/317719/ZV1968099001.pdf
- https://www.doc-developpement-durable.org/file/Culture/Arbres-Bois-de-Rapport-Reforestation/mangrove/mangroves.pdf
