Trigonostigma
Keilfleckbärbling ( Trigonostigma heteromorpha )
Trigonostigma is a genus of danios ( Rasborinae ) that are similar in terms of their appearance and have a common reproductive strategy. They are found in Thailand, Cambodia, Malaysia, Singapore and Indonesia in tropical Southeast Asia. In a very thorough investigation of the mitochondrial DNA of many carp fish in the genus Rasbora collection, it became clear that the criteria for the establishment of the genus Trigonostigma for a definition is not sufficient and must be the synonymisation with Rasbora.
Features
The size varies between about two and four and a half centimeters. The body is narrow and has an orange-red to reddish staining. From the middle of the body to the tail fin root is a black strip at the front widened or similar club- like a triangle with three types draws. While Rasbora heteromorpha is high backs, Rasbora has somphongsi a considerably long straighter lower body. The lateral line is strongly reduced and only extends over six to nine voided shed. The females are slightly larger and thicker than the existing spawning males. With a total length of up to 20 millimeters and a body height of about five millimeters Rasbora is somphongsi one of the smallest vertebrates.
Way of life
For reproduction form within an occupied and defended by the male coalfield short pairs. The fish are ovulipar, which means that the females lay eggs from which are then fertilized outside the body of only one male. The eggs are attached to the underside of plant leaves water in the course of a ritualized Balzspiels. Herein differ Keilfleckbärblinge from all other known Rasborinen that spawn in pairs or in groups freely over different substrates. Keilfeckbärblinge, like all cyprinids, no schooling fish, but living in socially responsive groups, of which reproductive prepare couples separate in the short term.
System
All four Trigonostigma species were first described as Rasbora. Because of their similar drawing and matching reproductive behavior presented Kottelat and Witte ( 1999) for the genus Trigonostigma on it. Studies of mitochondrial DNA of many Southeast Asian carp fish by Tang et al. (2010) gave arguments for a return to the genus Rasbora sensu lato, while another study by SO Kullander et. al. (2010) gives rise to the retention of the new genus Trigonostigma.
The genus Trigonostigma is composed of four types:
- Keilfleckbärbling, Rasbora heteromorpha, Duncker, 1904
- Hengel Keifleckbärbling, Rasbora hengeli, Meinken, 1956
- Conjoined Zwergbärbling, Rasbora somphongsi, Meinken, 1958
- Shivers Keilfleckbärbling, Rasbora, Meinken, 1967
The then head of the fish destination of the Association of German aquarium and terrarium Associations (VDA ), Hermann Meinken, had to Rasbora somphongsi in October 1958, although published a professional scientific species description, the style but in February 1958 in the enthusiast magazine DATZ so precise and with the new presented scientific names, that this popular item from the priority principle is the actual first description.
Also Rasbora espei was first described by Meinken in a Aquaristikzeitschrift as a subspecies of Rasbora heteromorpha. However, this publication does not contain any comprehensible diagnosis, so that the identity of the Rain by Both and Kottelat (1987 ) collected the species rank Rasbora espei not safe. Therefore, the status of the species is in doubt again and again.
The systematic position of the genus Trigonostigma by Liao, TY, SO Kullander & F. Fang within the Bärblingstribus Rasborini cladogram shows the following:
Trigonostigma
Horadandia
Rasbosoma
Rasbora
Brevibora
Kottelatia
Relevance to humans
All summarized in this genus species are popular and - with the exception of Rasbora Rasbora somphongsi and espei - regularly offered in the pet trade aquarium fish. From Rasbora heteromorpha there is a melanistic, a xanthoristische and a schleierflossige breed form. While Rasbora Rasbora heteromorpha and hengeli of large hatcheries in Thailand, Malaysia, Poland and the Czech Republic are increasingly encompasses virtually all traded Rasbora Rasbora espei somphongsi and wild-caught ..