Adult in Candelaria River
An adult of Thorichthys helleri in normal coloration in Candelaria River [Mexico].Photo by Juan Miguel Artigas Azas. determiner Juan Miguel Artigas Azas

Family
Cichlidae

Sub-family
Cichlinae

Tribe
Therapsini

Genus
Thorichthys

Group
Helleri

Status
valid


Curator

Published:

Last updated on:
17-Oct-2017

Thorichthys helleri (Steindachner, 1864)


Original description as Heros helleri:

  • Steindachner, Franz. 1864. "Beiträge zur Kenntniss der Chromiden Mejico's und Central-Amerika's". Denkschriften der Mathematisch-Naturwissenschaftlichen Classe der Kaiserlichen Akademie der Wissenschaften in Wien. v. 23 (n. 2); 57-74 (crc00248)

Synonyms (1):

Nomenclature history:

Etymology: There is no mention in Steindachner´s paper about for whom he named this fish, but most likely it was named after Karl Bartholomaeus Heller (1824-1880), an Austrian naturalist and professor at the prestigious Theresium school in Vienna (named after Empress Maria Theresa). He collected material that served as a base for T. helleri and several other fish descriptions. Of the seven cichlid species described in Steindachner´s paper, only Thorichthys helleri has a patronymic name.

Types: Syntypes: Six specimens stored at the Natural History Museum (Naturhistorisches Museum) [Vienna] with registration NMW 17344-49.

Diagnosis: Franz Steindachner states that as a main diagnosis trait, the higher body of Thorichthys helleri separates it from both T. aureus and T. affine. The distinctive fold in the lower lip of T. helleri, interrupted in the center, is also mentioned.

A diagnostic marking for T. helleri includes an elongated black blotch on the rear distal part of the dorsal fin on the males, from about the eighth hard ray back to the first soft rays. The females have a diffuse black blotch in the central part of their dorsal fins. Although this mark could differ in separated populations. Another distinctive feature is the pronounced downward sloped curve of the snout. The snout (the horizontal distance between the anterior extreme of the orbits and the tip of the lips) is noticeably shorter than in the rest of species of Thorichthys. The dorsal fin spines are also longer than in the rest of the congeners (Artigas Azas, 2007).

Size: Thorichthys helleri is a small cichlid with a record for 17 cm. (Resendez Medina, 1981) in total length, which I must stress that would really be a unusually large fish, probably counting fin filaments, as specimens larger than 13 cm for a male would be considered as extremely large, females rarely reaching 10 cm total length.

Sex dimorphism: Males grow larger than females (large females hardly reaching 10 cm under natural conditions) and have longer fin threads on the fins. Sex is also shown in adult individuals by the distinctive elongated black blotch on the distal part of the dorsal fin of males. This blotch is different between populations but in every population I know males can be distinguished from females by the shape and location of this blotch (Artigas Azas, 2007).

Common names: Bacchoy (native, Tzotzil), Mojarra amarilla (literature, Spanish), Yellow cichlid (literature, English).

Type locality: Río Teapa, Tabasco, Mexico.

Distribution: Thorichthys helleri is one of the most widely distributed Thorichthys species, inhabiting the lowland (up to about 200 m altitude) of the clear water river systems between the Rio Tonalá and the Rio Champotón, all flowing east to the Gulf of México. This includes the Rio Tonala and the lower Grijalva, Usumacinta, lower Tulija, Chompán, Candelaria and Champotón drainages. In Rio Usumacinta system it extends well into Guatemala tributaries in the Quiché and Petén areas. A population is known (Miller, 2005:377) in Rio Chiyú, which has underground connection with Rio Sarstoon, flowing to the east into the Gulf of Honduras and forming the border between Belize and Guatemala.

Although primary a riverine species, found in rivers and streams of moderate flow, some small populations also dwell in lakes and swamps, together with T. meeki. The latter species is, however, much more abundant in more stagnant and less oxygenated habitats.

Inhabited countries: Guatemala (native), Mexico (native).

Habitat: Thorichthys helleri is mostly found in areas of clear water, in pools of oxygenated rivers and creeks with moderate flow within its range. It is normally associated with jungle bordered sandy bottomed courses of water, with or without aquatic vegetation, rocks and driftwood. Water is normally clear or very clear, although some areas with some turbidity are also inhabited by the fish. T. helleri can be found over a bottom of sand, silt, gravel and sometimes mud, preferring areas with sunken leaf beds and driftwood. T. helleri is found sympatrically but in very small numbers with T. meeki, in the same kind of habitat where the fire-mouth inhabits, like lagoons (sometimes brackish), swamps and ditches, in muddy and poorly oxygenated water.

Water in the T. helleri habitat is always alkaline with a pH over 7.5 and normally very hard, but it can also be moderately hard. Temperature in my experience ranges mostly from 22 to 28ْْ C, with many measurements made over the years. Warmer temperatures are registered during the end of the dry season between March and May.

Thorichthys helleri is associated with numerous groups of fish species. Cichlids include members of the genera; Thorichthyts (meeki, pasionis), Amphilophus (nourissati, robertsoni), Chuco intermedium, “Cichlasoma” (octofasciatus, salvini, urophthalmus), Parachromis friedrichsthalii, Paraneetroplus gibbiceps, Petenia splendida, Theraps (irregulare, lentiginosus), Vieja (argentea, bifasciata, heterospila, pearsei, ufermanni and probably V. regani).

Localities: Candelaria River (Mexico, native), Champoton River (Mexico, native), Arroyo Cristal (Mexico, native), Oxolotán River (Mexico, native), Puyacatengo River (Mexico, native), Franja transversal norte (Guatemala, native), Chancala River (Mexico, native), Corzo River (Mexico, native), Lacanjá River (Mexico, native), Lake Lachuá (Guatemala, native), Miramar (Mexico, native), Nututun (Mexico, undefined), San Juan River (Guatemala, undefined), Subin River (Guatemala, native).

Feeding: Thorichthys helleri feeds in loose groups in shallow areas of the habitat. It wanders facing downwards and picking on the substrate, creating small pits in it, more than sifters Thorichthys are pickers, they do not systematically pick on every area of the substrate like sifter cichlid species (e.g. Crybroheros robertsoni) do, the way they locate their preys has not been studied to my knowledge. Material picked up is scrupulously examined in the mouth and inedible matter expelled through mouth and gills, while softer material is filtered by gill rakes. Thorichthys are carnivorous and I have never seen them collecting vegetable matter, although it may be ingested as a sub-product of the picking process.

Breeding: Thorichthys helleri starts breeding efforts in the last months of the dry season around March, when the water is clearer, warmer and the flow is slower. Breeding may extend to October but is drastically reduced after May, when the rains arrive. In my observations T. helleri normally selects territories in slower flow areas of the river, in many occasions over accumulations of fallen leaves that seem to hide their color pattern from above. Suitable areas may be occupied by many pairs, separated on occasion by no more than one meter. A solid surface in the form of a rock, wood or sunken leaf with surrounding cover is a valuable asset for a territory and males fight for such areas. Males defend territories prior to the formation of pairs, and start courting passing females by assuming a slightly head down position, extending fins and slightly shaking their bodies. Females, smaller in size, respond by circling males with their fins extended in ever tightening circles. At one point pairs get side by side while males, with undulating movements of the body, push water at the females in an apparent effort to show their strength. If a female decides to stay with the male, they start a vigorous side-to-side courting motion while circling.

Alternatively pairs form without the previous establishment of a breeding territory and once formed both pair wander the habitat in search and establishment of one, apparently for some days judging from aquarium observations.

At one point the territory is defended by the new pair. They defend their territory by making small frontal runs towards neighboring pairs with their gular pouches and opercular plates extended. In this situation the black blotches on the extended operculum give them the appearance of bigger fish, and other fish are normally intimidated without a fight. On a few occasions pairs get to their counterparts mouths and bite them, but without any damage being produced.

T. helleri cleans the spawning surface vigorously with their mouths prior to depositing their ovoid yellowish translucent eggs in tight circles. I would estimate spawns of about 100 to 200 eggs, depending on the size of the female. Females watch over their spawn, circulating water among eggs with their pectoral fins, while males chase intruders away from the territory.

In Lake Miramar (Konings, 2014) we were able to witness sneaker behavior in a spawning pair of Thorichthys helleri, first spotted by Ad Konings for any Central American cichlid (look video accompanying this profile). A sneaker male was hidden with a subdued coloration behind a rock close to the spawning site and at the smallest distraction of the pair he rushed in to occupy a position just above the eggs and quickly proceeded to fertilize them, just to dash away as rapidly as he came in, often followed close by the male.

Eggs hatch in about 48 hours under aquarium conditions at 28 °C. Small pits in the substrate are excavated by the pair where they place the newly hatched wrigglers; subsequently wrigglers are transported by the female from one pit to another several times a day. Five to six days later the yolk sac, with which the babies are born, is fully consumed and the little babies start making swimming attempts inside their pits. The next day, with all the wriggler now swimming, the pairs school them around the territory.

I have followed pairs for hours and have seen that they always circle the same area around the nest, not venturing more than a few meters away, and it is probable that they use the same pits for night cover. Herding their babies the pair behaves as other Central American cichlids do: the females closely guarding the babies and guiding them. Signaling is achieved with spasmodic body shakes and with rapid opening and closing of the fins. Males, also signaling, take the lead.

Fry appear to decrease in number with the passing of the days and when babies reach about a centimeter (in aquarium, about four weeks post spawning) they are normally (but not always) significantly fewer in numbers. Predation pressures, especially from other fish such as Astyanax ssp., take a toll on the fry.

Babies seem to feed picking on the surfaces that they pass, and females don’t seem to make any special effort (unlike other Central American cichlids) to provide food for their babies.

When babies abandon their parents at a little over a centimeter and half in length (about two months post spawning) they congregate in covered shallow areas of the habitat, where they are seen in the company of many other young fish.

Aquaristics: Thorichthys helleri has apparently been known in the aquarium hobby for a long time, longer even than its popular relative, T. meeki. Walter Lannoy Brind, an early New York aquarium fish distributor, mentioned them in the T. helleri meeki (Firemouth) description in 1918, published in Aquatic Life magazine. He then considered the Fire-mouth as a subspecies of T. helleri. Over the years there have been ups and downs in the mention of T. helleri in the aquarium literature, probably because of the following reasons.

When keeping T. helleri, remember its habitat preferences. Unlike T. meeki, T. helleri cannot successfully thrive in low oxygen, bad quality or warm water (over 28 ̊C) conditions. It likes cool and oxygenated water, within its natural parameters. If water loses quality, bacterial infections and hole-in-the-head are likely to strike.

Although not very aggressive and hardly ever damaging each other, I would not recommend anything less than 300 liters for housing a group of Thorichthys helleri. As for decoration, I prefer somewhat natural looking aquariums with boulders and driftwood, with a fine sand substrate that allows them (and me) to enjoy their natural picking behavior. You can then notice that at feeding time many small pits are dug on the sandy surface of the aquarium.

Natural shyness is easily overcome with dither fish. I have used large Poecilia species, naturally occurring with T. helleri in some areas of the habitat. Any other large Poeciliids. (or other large dither fish) would do just fine. Just try to avoid fish that bite on the fins, as they can produce a counter effect to what you are looking for. Small dither fish may be eaten by adult T. helleri.

Providing for food is no problem; they are eager eaters when conditions are right. I consider Thorichthys of the T. helleri group a delicate fish in terms of diet, and although they are carnivorous in nature, I suggest to avoid diets with terrestrial animal proteins to avoid clout. It worked well for me.

As for breeding, if conditions are right, nothing will stop them from trying. I use inverted flower pots with the bottom opened as nest possibilities and they love them and readily use them, but readily spawn in open areas as well. They do not become too aggressive in breeding time and in fact you can raise a group of babies in the home aquarium, again, if conditions are right. You may however fail the first few occasions as they are quite shy and nervous but you will eventually succeed, and it is wonderful to observe their full pattern behavior in the home aquarium!

Thorichthys are a joy to keep in the home aquarium. They are interesting, not very aggressive, and wonderfully colored Central American cichlids.

Conservation: Thorichthys helleri is not evaluated by the international union for the conservation of nature in the iucn red list of threatened species.

Comments: As with many other cichlids, much is yet to be learned about this wonderful fish, a Mayan-land jewel of beautiful colors and gentle disposition. The colors of a healthy individual are one of the most beautiful sights you can have in the freshwater world. Give this splendid fish a chance!!.

References (13):

  • Artigas Azas, Juan Miguel. 2007. "Thorichthys helleri (Steindachner, 1864), the Mojarra Amarilla from Mexico". Cichlid News Magazine. v. 16; n. 1; pp. 22-28 (crc01380)
  • Brind, Walter L.. 1918. "A new subspecies of Thorichthys helleri". Aquatic Life. 3 (8); pp. 119-120 (crc00274)
  • Eigenmann, Carl H & C. H. Kennedy. 1903. "On a collection of fishes from Paraguay, with a synopsis of the American genera of cichlids". Proceedings of the Academy of Natural Sciences of Philadelphia (crc00070)
  • Eigenmann, Carl H. 1893. "Catalogue of the fresh-water fishes of Central America and Southern Mexico". Proceeding of the United States National Museum. vol. 16 (n. 925): pp53-60 (crc02506)
  • Jordan, David Starr & B.W. Evermann. 1896. "Checklist of the fishes and fish like vertebrates of North and Middle America". Report of the Commissioner of Fish and Fisheries. XXI: 207-584 (crc02517)
  • Konings, Ad. 2014. "Sneakers and streakers". Cichlid News Magazine. v. 23(n. 4), pp. 18-21 (crc06405)
  • Meek, Seth Eugene. 1904. "The fresh-water fishes of Mexico north of the isthmus of Tehuantepec". Field Columbian Museum Publication. pp. 1-252 (crc00159)
  • Miller, Robert Rush. 2005. "Freshwater Fishes of Mexico". University of Chicago Press, Chicago. pp. 1-524 (crc01245)
  • Miller, Robert Rush & J.N. Taylor. 1984. "Cichlasoma socolofi, a new species of cichlid fish of the Thorichthys group from northern Chiapas, Mexico". Copeia. pp. 933-940 (crc00272)
  • Miller, Robert Rush & B.C. Nelson. 1961. "Variation, life colors, and ecology of Cichlasoma callolepis, a cichlid fish from Southern Mexico, with a discussion of the Thorichthys Species Group". Occasional Papers of the Museum of Zoology, University of Michigan. (n. 622), pp. 9 (crc01100)
  • Regan, Charles Tate. 1905. "A revision of the fishes of the American cichlid genus Cichlosoma and of the allied genera". Annals and Magazine of Natural History. (Ser. 7) vol. 16; pp 60-77; 225-243; 316-340; 433-445 (crc00042)
  • Resendez Medina, Andrés. 1981. "Estudio de los Peces de la Laguna de Términos, Campeche, México. II. Última parte". Biótica. v. 6(n. 3), pp. 239-291 (crc04093)
  • Steindachner, Franz. 1864. "Beiträge zur Kenntniss der Chromiden Mejico's und Central-Amerika's". Denkschriften der Mathematisch-Naturwissenschaftlichen Classe der Kaiserlichen Akademie der Wissenschaften in Wien. v. 23 (n. 2); 57-74 (crc00248)

Citation:

Artigas Azas, Juan Miguel. (October 17, 2017). "Thorichthys helleri (Steindachner, 1864)". Cichlid Room Companion. Retrieved on November 23, 2017, from: https://www.cichlidae.com/species.php?id=246.