The species we will introduce here is Oryzias songkhramensis, which was just described as a new species last year.It is a small species closely related to O. minutillus, O. mekongensis, and O.pectoralis, both of the same genus.

Its distribution area is the Mekong River basin from northeastern Thailand to central Laos. The species name is derived from the Songkhram River in the Mekong River system in northeastern Thailand, where this species is distributed.
At first glance, it looks quite similar to Minutilus, a member of the same genus, but when this species settles down, the peritoneum becomes black, giving the appearance of a black line on the side of the body. It is also characterized by a small black spot at the base of its pectoral fins.
This species does not have the small black spot near the excretory opening that is seen in Minutilus, so it is easy to distinguish.
This species was described as a new species in April 2010, but its existence was known even before then, and the fact that it was imported to Japan is probably unknown to anyone other than enthusiasts. At that time, some thought that it was a poor Mekonensis with no red on its tail, and that it may have been mistakenly identified as Minutilus. However, when we confirmed the collection location, it was definitely in northeastern Thailand, and since the distribution area is clearly different from that of Minutilus, it was dismissed as just a regional variation of Mekonensis.

When this species was imported to Japan in the past, I saw it in the stock aquarium of the importer in Tokyo, but the water was colored due to the chemicals in it, and it was not calm, so it had a distinctive color. Because there was no ``,'' I overlooked that it was a new species.

It is very important to observe these delicate small fish in a calm state in your home aquarium. When looking at fish, you have to let go of your preconceived notions, but sometimes I forget this, so I have to reflect on this. Last year, I obtained a paper describing this species, and found that its distribution range in Thailand and Laos is a place I had previously visited several times to photograph and collect. Orygias like this species are very easy to spot locally as they swim in groups on the surface of the water. So, although I knew of its existence, I always thought it was Mekonensis and neglected to scoop it up with a net to confirm.

Last November, I finally had the opportunity to go to Thailand and Laos, which was my long-awaited chance to see where this species lives.
We began our search in Vientiane, Laos, and were able to confirm that this species was living in a rice field on the outskirts of the country. Next, we entered the Thai side from Nong Khai and headed to Ratanawapi, where the holotype of this species was collected. The dry season has already begun, and all the rice fields are dry. As they searched for water, they found a vast wetland. Just as I had a hunch that it would definitely live here, I immediately caught sight of this species swimming on the surface of the water. I quickly scooped it up with a net, transferred it to a plastic bag, and checked it. It's definitely Songkramensis.

The one shown in this photo is an individual collected at this location. There is information that in addition to Songkramensis and Mekonensis, Pectralis also inhabits the northeastern part of Thailand called Isan. I haven't seen Pectralis with my own eyes yet, so this is a challenge for the future. Perhaps there are new origias in addition to these. If I have a chance, I would like to continue exploring small Origias.

Lastly, breeding is easy, as long as the chlorine is removed from tap water in Japan, there is no need to adjust the water.
Small baits like brine shrimp are best, but you can also feed them finely chopped flake bait. Breeding is easy if kept in good conditions. Spawning often takes place in the morning, and you may be able to see them swimming with eggs, which are slightly larger than their bodies, attached to their abdomens.