Pachypanchax arnoulti
| Pachypanchax arnoulti | ||||||||||||
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| Scientific name | ||||||||||||
| Pachypanchax arnoulti | ||||||||||||
| Loiselle , 2006 |
Pachypanchax arnoulti is afish that livesin northern Madagascar . The species name refers to Jacques Arnoult, who first introduced a number of Malagasy fish species to science and aquaristics in the 1950s.
distribution and habitat
The species inhabits the Mahavavy du Nord and Betsiboka river basins . Between the mouths of these two rivers, it is also found in a number of small streams that flow into the Mozambique Strait . There are also known finds from a mountain stream in the Tampoketsa highlands . Some other potential sites still require confirmation. The water of origin of the type specimens is a swamp with few plants, with clear, tannin-colored and with less than one degree of German hardness (<17.1 ppm ) very soft water. The water is slightly acidic with a pH of 6.2 and has a very low conductivity of only 16 μS / cm² .
Appearance
The species reaches a standard length of almost six centimeters and shows the typical body shape of the genus Pachypanchax . Compared to the other species, P. arnoulti has the proportionally longest head, making up about 30 percent of the standard length. Nine to eleven gill trap processes sit on the first gill arch. A narrow white border delimits the anal fin and the lower corner of the caudal fin . There are 29 to 33 cycloid scales along the sidelines .
- Dorsal II-III / 8-12
- Anal II-III / 12-17
- Pectorals 14-16
- Ventral I / 5
Way of life
Like practically all of its relatives already described, P. arnoulti feeds on insects that have fallen into the water as well as larvae and nymphs of water-dwelling insects. In addition to predatory fish such as the flat-headed goby ( Glossogobius giuris ), fish-eating birds and dragonfly larvae prey on it. The breeding season of the species probably extends over the entire rainy season.
status
The condition of the different populations of P. arnoulti fluctuates within the relatively wide range. In some locations, the species is increasingly being pressurized by neozoa . The swordtail ( Xiphophorus helleri ) and the gambus species Gambusia holbrooki play a special role .
literature
- Paul V. Loiselle: A review of the Malagasy Pachypanchax (Teleostei: Cyprinodontiformes, Aplocheilidae), with descriptions of four new species. Magnolia Press, 2006 ( Download , eng., PDF; 676 kB)
Web links
- Pachypanchax arnoulti on Fishbase.org (English)