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Ryusho Hoshi Medaka
AdvancedOryzias latipes
An improved medaka with black rim markings over transparent-scale vermilion, combining hirenaga long fins with the hikari body type. Created in 2020 by Kazuaki Senoo, it also carries vivid fin colour.
Difficulty
Advanced
Temperature
18〜28℃
Lifespan
2-3 years
Size
Up to about 4cm SL
Diet
Prepared medaka food, green water
About
Ryusho Hoshi was created in 2020 by Kazuaki Senoo; its classification name is the vermilion transparent-scale black-rim hirenaga hikari medaka, with the common note hire-bi. The Medaka Web Encyclopedia registers it as type No.0649 and variety No.0628, describing it as a strikingly elegant fish thanks to the vivid colour carried in its fins. Black rim is the trait in which dark markings emphasise each scale; unlike blotching it does not break up but spreads evenly over the whole body. On the head the black tends to appear along the scale margins, while toward the tail it gathers at the centre of each scale. It was once seen mainly in semi-transparent-scale lines, but crossing with transparent scale brought it into those lines too. Hire-bi appears mostly on transparent-scale varieties, and covers both fins more vividly coloured than the body and colour appearing where it usually does not.
Source: Wikipedia (CC BY-SA 4.0)
Lifespan of the Ryusho Hoshi Medaka
The Ryusho Hoshi Medaka lives 2-3 years.
Size of the Ryusho Hoshi Medaka
The Ryusho Hoshi Medaka grows to Up to about 4cm SL.
Temperature & humidity for the Ryusho Hoshi Medaka
The ideal temperature for the Ryusho Hoshi Medaka is 18〜28℃.
Basic Info
Origin
Japan (domestic variety created in 2020 by Kazuaki Senoo)
Lifespan
2-3 years
Care Specifications
- pH
- 7–8
- Hardness (GH)
- 9–19 dGH
- Water Temp.
- 18–28℃
PeacefulGroupBreeding: Hard
Sources: Medaka Web Encyclopedia: Complete Medaka Care Guide / FishBase Oryzias latipes / Medaka Web Encyclopedia No.0649
Morphs (Varieties)
The Japan Medaka Association's classification manual sorts varieties by traits that can be seen rather than by genotype, and does not set out how individual traits are inherited. Traits the manual explicitly says can be passed on and produced by selective, multi-generation breeding are listed as line-bred; the rest are grouped under Other.
Other
Vermilion body colourTransparent scaleBlack rimHirenaga (all-fin elongation)Hikari body typeHire-bi (vivid fin colour)
Sources: Japan Medaka Association: Variety Classification Manual, 5th ed. (Sep 2025) / Medaka Web Encyclopedia: Medaka Traits / Medaka Web Encyclopedia No.0649
A curated selection of notable morphs. Inheritance modes are a breeding-planning guide; actual appearance varies with combos.
References & Sources
Edited & verified by: BreederDirect editorial team
The taxonomic, regulatory, and husbandry data on this page are compiled and verified against the authoritative primary sources below.
Primary sources
- Wikipedia
- CITES Appendices (species not listed)
- FishBase (IUCN Red List: Least Concern, assessed 2018)
- Medaka Web Encyclopedia: Complete Medaka Care Guide
- Medaka Web Encyclopedia No.0649
- Japan Medaka Association: Variety Classification Manual, 5th ed. (Sep 2025)
- Medaka Web Encyclopedia: Medaka Traits
- FishBase
- GBIF
Taxonomy & Authority
Accepted name: Oryzias latipes (Temminck & Schlegel, 1846)
Breeder: 妹尾和明 (2020)
Authority databases: FishBase · GBIF · Medaka Web Encyclopedia No.0649
Nomenclature follows global taxonomic authority databases.
Regulations & Conservation Status
Not CITES-listedIUCN LC · Least Concern
Sources: CITES Appendices (species not listed) / FishBase (IUCN Red List: Least Concern, assessed 2018)
Regulations may change. Always verify the latest information with the relevant authorities.
Ryusho Hoshi Medaka Listings
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