Discovery, Pursuit and Capture of Theraps wesseli

Collecting site of Theraps wesseli. Photo by Rusty Wessel.

In March 1991, I found myself collecting cichlids with fellow cichlidophiles Ross Socolof and Dr. Harry Specht on the Caribbean coast of northern Honduras. As usual, I was the first to enter the water. Equipped with a dive mask, I was pleasantly surprised to spot a fish in the river I had never seen. When I saw the fish I screamed to Ross to come see it before it vanished beneath the massive boulders in the rapids of the river. On first sight I knew this fish must be new and once Ross viewed it he agreed with my assessment. Subsequently, after some 12 trips to this area over a five-year period, this cichlid was named Theraps wesseli, in my honor, by Dr. Robert Rush Miller of the University of Michigan. The species description was published in the June 1996 issue of Tropical Fish Hobbyist. My intent here is to describe the habitat of Theraps wesseli and how difficult a fish it was to capture. Perhaps this difficulty is the reason it has gone undescribed this long.

Rio Jutiapa in Honduras. Collecting site of Theraps wesseli. Photo by Rusty Wessel.

Theraps wesseli exists in at least three streams in Northern Honduras, the Rio Juhapa, Rio Belleaire and the Rio Hauron. All of these streams are part of the Rio Papaloteca basin in the Departmento de Atlantida between the coastal city of La Ceiba and Sava (Saba on some maps). All three streams originate in the coastal Cordillera Mountain range and flow in the Caribbean Sea. Clouds constantly hug the mountain range and provide clean, pure water to these pristine mountain streams. The water clarity during the dry season (January to June) is spectacular. The crystal clear stream consist of fast moving water with a current of approximately three feet per second, a pH of 7.8 and a water temperature of approximately 25°C (77°F.) Surprisingly, the water is relatively soft. The bottom consists of sand, rocky rubble and large boulders with a maximum depth of only 2.4-3.0 m (8 to 10 feet.) The banks are lined by a lush green vegetation. Many consider this the area on of the most beautiful areas in all of Honduras.

Theraps wesseli lives in the fastest current in the river. This rapid loving cichlid is similar in color to Melanochromis auratus from Lake Malawi in east Africa. During normal coloration, the male and female have a narrow black strip extending from the eye to the base of the caudal fin. Above and below this mid-lateral stripe a gold stripe can been found. The overall body coloration is from tan to yellow. The tips of the dorsal and anal fin are chalky blue, as are the scales along the flanks. During courtship, the body below the mid-lateral stripe turns jet black in both sexes. This breeding color phase begins a week or so before spawning and lasts until the fry have left the nest. It is during courtship that this animal is most strikingly similar in color to M. auratus. Distinguishing the sexes is difficult, except during the height of courtship when the black color of the female intensifies. The fry at one inch are exact replicas of the adults. This asset should make these popular with aquarists because most young Central American cichlids are dull gray as juveniles.

Theraps wesseli in normal coloration. Photo by Rusty Wessel.

As I mentioned above, Theraps wesseli is at home in the rapids of the river and is quite rare in its habitat. My most liberal estimate is that there is only one T. wesseli in every 1000 fishes in the stream. Not only is it rare, but its life in the rapids make it extremely difficult to capture. In addition, at the slightest disturbance, the animal quickly vanishes into the cracks of the boulders. The trick to capturing this elusive cichlid was going after them at night. Equipped with underwater lights and braving the rapids at night, eventually, and with much difficulty, after numerous sightings and hours of fruitless pursuit, specimens were captured. It should be noted that these relatively peaceful flowing streams became raging torrents during the height of the rainy season (July to December). The bridge at Jutiapa was completely washed away during a storm in 1993. It's amazing how fish can withstand such torrents in nature.

Archocentrus spilurus 'cutteri' from Rio Jutiapa, Honduras. Photo by Rusty Wessel.

Other inhabitants of the stream include an undescribed molly (Poecilia) that is commonly called "bar-tail" because of the black crescent on the caudal fin. Poecilia mexicana, Alfaro huberi, Xiphophorus helleri (green swordtail), Belonesox belizianus (pike top minnow), Gambusia sp., Heterandria bimaculatus, Phallichthys amates and an undescribed plant which only grows in the fastest rapids, all occupy the streams with T. wesseli. Also in the rapids, along side of T. wesseli, was an interesting gobie, Sicydium gymnogaster. It has fused pelvic fins which serve as a suction cup and allow it to "hang on" to rocks in the rapids. Freshwater crabs and large shrimp scurry along the bottom in search of food. Even though there are many interesting fish in these streams, it is the cichlids that fascinate me the most. The slack areas are inhabited by Amphilophus robertsoni, and a color morph of Archocentrus spilurum known as "cutteri." A. robertsoni is a medium-sized blue cichlid that constantly sifts through the sand for food. It avoids fast flowing water and is quite relaxed in the warmer back waters. Archocentrus spilurum are well represented throughout the streams but seem most at home in the moderately flowing water. They keep along the bottom of shallow water and could be found along the occasional vertical rock walls that formed the edge of the stream in places. It would peck at the substrate as if tearing of mouthfuls of food and whatever algae and debris was there. Currently, as with many cichlids, this particular color morph of A. spilurum is still under taxonomic review. The "cutteri" from this area have a beautiful blue streak through the mid-section of the body and have wine-red fins, distinctive from the gray A. spilurum from neighboring Belize to the west.

In closing I would like to thank the following people for either direct and indirect help in my pursuit of this elusive cichlid: Vance Alford, Carl Barker, Garlan Bird, Carl Bischoff, Phil Clary, T.J. Delahanty, Thom Grimshaw, David Herlong, Andy Jackson, Don Kink, Paul Mann, Eddie Martin, Richard Peake, Charlie Pyles, Tim Rohleder, Todd Sanchez, Steve Sears, Keith Sheppard, Ross Socolof, Harry Specht, Dick Thomas, and Morgan and Suzie Wessel.

This bridge was washed out by the raging flow of the Rio Jutiapa during the rainy season. Photo by Rusty Wessel.