SMITH & MILLER, 1986
Characodon audax SMITH & MILLER, 1986
Characodon spec. RADDA, 1984
Characodon audax SMITH & MILLER, 1986
English name:
Bold Goodeid Family:
Goodeidae JORDAN, 1923 Subfamily:
Goodeinae JORDAN, 1923 Original description:
SMITH & MILLER, 1986: Mexican Goodeid Fishes of the Genus Characodon, with Description of a New Species. American Museum Novitates No.2851 pp. 1-14. Derivation of the species name:
named audax in reference to its aggressive nature. Type locality:
Source at El Ojo de Agua de Las Mujeres, close to the town El Toboso, Durango, Mexico. Together with Hubbsina turneri Characodon audax seems to be the most wanted Goodeid at present. During a collecting expedition in the north of Mexico in 1982 R.R. MILLER and his colleagues caught a Goodeid in a pond close to Ojo de Agua de Las Mujeres, which was fed by a spring. The outer look of the fish was distinctly different to the only well-known species of the genus Characodon, Characodon lateralis (GUENTHER 1866). In 1986 the species was described as Characodon audax. The name "audax", which would be translated from Latin as bold or daring, indicates the aggressive character of this small Goodeid. The shape of Characodon audax strongly resembles C. lateralis. A reliable distinctive feature is the number of dorsal fin rays, which is exactly one less in the case of Characodon audax with 10 (females) to 11 (males) than in the case of Characodon lateralis. Also the pectoral fins of the males are a little bit smaller. A still more prominent difference is the colouring of the males. While Characodon lateralis displays yellow and red tones on a greenish background, the males of Characodon audax are nearly black. Only the area around the abdomen and the pectoral fins as well as chest and throat are yellowish-orange. On the sides of the body are some silvery or bluish gleaming scales. This appearance gave the fish its trivial name "black prince". The females of Characodon audax and Characodon lateralis are hard to differentiate and therefore should not be kept together. The ovary of the Characodon audax females is designed as that of most other Goodeids. The trophotaenia of the young are very similar with those of Characodon lateralis. Investigations on the chromosome structure have revealed that Characodon audax, just as Characodon lateralis, has 24 large diploid, metacentric chromosomes. Since the most primitive Goodeids have 48 telocentric chromosomes, Characodon is a more highly developed genus. At this time Characodon audax has only been found at its type locality which is one of a few smaller springs, all flowing into a lake that occasionally dries up in the semiarid basin of the Laguna El Toboso. This lagoon is only separated by a small threshold of no more than 50 meters height from the neighbouring occurrences of Characodon lateralis. Characodon audax populates the brook, whose ground exists of mud, sand and some stones, as well as the pond. This small Goodeid does well in aquariums from 50 litres on up in size. Because of the high inner-species aggressiveness (the males only) however many hiding places (stone superstructures, wood) and a dense vegetation must be present. Keeping several males is favourable also with this species, since the aggressions will be distributed on several individuals and thus the pressure on each individual male is reduced. Fighting between the males can be so intense that an involved fish sometimes dies of the consequences. All specimens of Characodon audax in Europe probably descend from only 2 pairs, which DGLZ member IVAN DIBBLE got directly from the USA collection of Professor MILLER. This species does well in alkaline water with a temperature between 22 °C and 24 °C. Live-food is preferred, while scalded spinach, frozen food and flakes are willingly accepted. As an additional source of food, algae vegetation in the aquarium is welcome. Maturity is reached approx. 4 months after birth. The young do not grow very fast. The sexes can be differentiated after approximately six weeks. Breeding succeeds frequently. Younger females deliver up to 10 young about every two months. IVAN DIBBLE reported of a litter of 63 fry from a particularly large female. Characodon audax can be crossed with Characodon lateralis. Therefore these two kinds should not be kept together. In 1990 Dr. DIETMAR KUNATH, Germany, was involved in crossing Characodon audax and Characodon lateralis. This is the report: Crossing of species-, genus or even family hybrids certainly permits conclusions in genetic and taxonomic direction and permits at the same time certain statements about the depth and the age of a species as well as about their descent. Specimens of different species do not cross if the formation of the species took place early and has become species-specific enough. In this respect one has to distinguish between voluntary and forced crossing, the latter under the condition of close socialization. Especially with livebearers and their internal fecundity many parameters can be experimentally varied between voluntary and forced crossing. The results if appropriately described can increase ichthyologic knowledge. In a densely planted 70-litre-tank (Vallisneria spiralis forma tortifolia) I have kept since March 1989 the following species of Goodeidae (JORDAN, 1880): Ataeniobius toweri (MEEK, 1904) 2/1/0 (that means: 2 adult males, 1 grown-up female, 0 young), Characododon audax (SMITH & MILLER, 1986) 1/1/0, Characodon lateralis (MORE GUENTHER, 1866) 11/8/10, Skiffia bilineata (BEAN, 1898) 4/5/6, Skiffia francesae (KINGSTON, 1978) 3/3/4, Xenotoca variata (BEAN, 1888) 1/1/0 and Zoogoneticus quitzeoensis (BEAN, 1898) 1/1/0. While Ataeniobius toweri, Skiffia bilineata, Skiffia francesae and Xenotoca variata could be bred only by separation of pregnant females and/or freshly delivered young, Characodon lateralis reproduced itself without any help. The Zoogoneticus quitzeoensis died without producing offspring in May/August 1989. After being put into the 70-Liter-Aquarium, Characodon audax delivered some young twice, which did not survive however. On September 11th 1989 one highly pregnant Characodon audax female was therefore set into a separate 20-litre aquarium, where it delivered six young on October 4th 1989 and seven young on October 5th. First they showed a regular grey colouring, thus completely different juvenile colouration than Characodon lateralis. On November 11th 1989 four males and 9 females could be identified, which had a striking similarity with adolescent Characodon lateralis. These fish were always kept separately from other Characodon. Today these animals are about 3 cm long and look like this: Male of the hybrid Characodon lateralis x Characodon audax
illustration: Dr. DIETMAR KUNATH On the basis of the two illustrations below (by Dr. DIETMAR KUNATH) it is visible that the hybrid has characteristics of both species. The red coloration corresponds to the red coloration of Characodon lateralis. These animals might certainly be a crossing between a male of Characodon lateralis and a female of Characodon audax. The Characodon audax - female delivered just once more again on January, 1st 1990 in the community tank; a young fish with a length of 8-9 mm could be observed several days, without being harmed by the other fish. The Characodon audax-male died on the March,12th 1990 and has kept its species-characteristic colouring to the end. There were no signs of outside pathogens and the fish was also well fed (approx. 4.5 cm length). The female did not recover after the last litter, so its death had to be expected. The Characodon hybrids are still kept separately. So far it seems that the fish will be fertile; some females appear to have rounded belly portions. This crossing between Characodon lateralis and Characodon audax can probably neither be defined clearly as voluntary nor as forced, since all sexes of both kinds were always present in normal condition. Unfortunately no statement can be made whether the two previous throws and the following throw produced hybrids, too. This coincidental crossing could encourage further attempts, however with the urgent request to spread no hybrids uncontrolled. On January 9th I received the message that Characodon audax was considered to be extinct in its natural environment. BRIAN KABBES, a Dutch friend of Goodeids, visited the only known habitat in 1999 and noticed a certain endangerment. When he visited the site again on December 7th 2000 he had to witness that there was no water present anymore. |
Characodon audax has become extinct
by BRIAN KABBES After SIMONE and BRIAN KABBES visited El Toboso (Durango, Mexico) in 1999 and recognized that the habitat of Characodon audax was to be classified as critically endangered, both visited this place again in the year 2000. On December 7th 2000 we were heading to El Toboso again. Already on the trip to the dusty desert village we were alarmed. In the previous year there was still a rather large marshy area outside of the village, where we could catch a large number of Characodon audax and Gambusia senilis. Today, this area is dry except two shallow puddles, in which we could find no organisms at all. It seemed that the formerly marshy area had become completely dry at the beginning of the yearly 2000. An inquiry revealed that this had been the case. Water originating from a well within the village permanently flooded the swampy land outside the village. Some years ago a water pump was built on this well to pump the water to a nearby water tower. I presume that the building of this water pump and its high capacity is the reason, why Characodon audax has become extinct. The quantity of water in the well has likewise decreased strongly. Some water has remained however and herein only Gambusia senilis existed. Also this site seemed to have almost dried in the course of the year 2000. The fact that Gambusia senilis could increase here that fast again is an example of the great ability of life-bearing tooth carps to adjust and to keep up. All fish found seemed to be adolescents and along with adults which remained small. Despite an extensive search no specimen of Characodon audax could be discovered. In the aquarium Goodeids remain smaller and have less resistance power when the living conditions are bad. This characteristic was crucial for them in the long run. Considering the habitat of this very much-isolated species it is assumed that the species Characodon audax became extinct in nature during the course of the year 2000. In the surrounding area there is no continuously existing water anymore. In the Netherlands and other countries extensive aquarium populations still exist. BRIAN KABBES, January 2001 On January 12th, 2001 I received a new and more positive message concerning Characodon audax. |
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Dedicated Aquarists who intensively deal with Goodeids have of course recognized the information provided by BRIAN KABBES about the destruction of the natural habitat of Characodon audax in Mexico. So a short while after the information had become public I received a message from Mexico via Great Britain and the Netherlands saying that there must be another natural habitat of Characodon audax, since in the photos by BRIAN KABBES (see above) other locations are shown, than those familiar to Goodeid enthusiasts from Mexico and Great Britain. The pictures above do not show the well-known C. audax habitat, but its vicinity.  |
In December 2001 Mr. JUAN MIGUEL ARTIGAS AZAS from Mexico sent the following text concerning Characodon audax to me: Hello,
You surely would like to know that I visited the El Toboso source in the last week. The habitat of Characodon audax is safe and stable – just like in the past. The population of the Characodon audax appears to be large and it seems prosper well. I spent a whole afternoon in the area and also visited another source, which is approximately 3 kilometres distant from El Toboso, an area without roads. Here was also the place of residence of the legendary revolutionist Pancho Villa. The source that I found had a low water level and a similar environment as the source at El Toboso, although the area is more isolated. A resident told me that the water level of the source had sunken during the last years (in contrast to El Toboso) without any obvious reason. It seems as if strong pumps somewhere interrupt the underground water flow feeding the spring. I have been told that last spring Characodon had still existed there and that it was seen also one year ago. But I found none. There is still enough water for a population of fish, but I saw no fish; only aquatic plants and insects. To be honest, I believe that there is not one fish anymore, although I naturally may err. I thought that this might be of interest in the face of all the rumours concerning C. audax. Juan Miguel |
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Taken from: Aqualog publishing company
Title: all Livebearers and Halfbeaks,
Photo by: E. Puerzl
Habitat: Coahuila, Mexico, wild form, male, 5 cm.  |
Taken from: Aqualog publishing company
Title: all Livebearers and Halfbeaks,
Photo by: H. J. Mayland
Aquarium population, bred in captivity, male, 5 cm.  |
Taken from: Aqualog publishing company
Title: all Livebearers and Halfbeaks,
Photo by: Manfred K. Meyer
Aquarium population, bred in captivity, male, 5 cm.  |
Taken from: Aqualog publishing company
Title: all Livebearers and Halfbeaks,
Photo by: MANFRED K. MEYER
Aquarium population, bred in captivity, female, 6,5 cm.  |
Taken from: Aqualog publishing company
Title: all Livebearers and Halfbeaks,
Photo by: J. C. MERINO
Aquarium population, bred in captivity, male, 5 cm.  |
Taken from: Aqualog publishing company
Title: all Livebearers and Halfbeaks,
Photo by: J. C. Merino
Aquarium population, bred in captivity, female, 6,5 cm.  |
Characodon audax  |
Characodon audax
place of discovery: El Toboso, Durango, Mexico  |
Characodon audax
place of discovery: El Toboso, Durango, Mexico  |
Characodon audax
place of discovery: El Toboso, Durango, Mexico  |
Characodon audax
place of discovery: El Toboso, Durango, Mexico
Photo by Uwe Dost  |
Characodon audax
place of discovery: El Toboso, Durango, Mexico
Photo by Uwe Dost | 
