AI-generated image
Reckless Medaka
IntermediateOryzias latipes
An improved medaka with dense fine glitter over a bright yellow aurora body and elongated fins. Created in 2021 by Mai Medaka, its name comes from the English word reckless.
Difficulty
Intermediate
Temperature
18〜28℃
Lifespan
2-3 years
Size
Up to about 4cm SL
Diet
Prepared medaka food, green water
About
Reckless was created in 2021 by Mai Medaka; its classification name is the yellow semi-transparent-scale glitter hirenaga medaka. The Medaka Web Encyclopedia registers it as type No.0871 and variety No.0840, describing it as a fish characterised by a bright yellow aurora body, glitter and hirenaga fins: the glitter is strongest seen from above, but the glitter in side view and the fins richly marked with yellow are attractions in their own right. The name comes from the English word reckless. Aurora is another term for semi-transparent scale, an expression midway between normal and transparent scale that lends the body a translucent quality. Semi-transparent-scale fish show yellow pigment in patches, and glitter on them tends to appear in several colours. The hirenaga trait, created in 2015 by Katsujiro Matsui, elongates every fin including the membrane, which distinguishes it from the long-fin trait that extends the rays alone.
Source: Wikipedia (CC BY-SA 4.0)
Lifespan of the Reckless Medaka
The Reckless Medaka lives 2-3 years.
Size of the Reckless Medaka
The Reckless Medaka grows to Up to about 4cm SL.
Temperature & humidity for the Reckless Medaka
The ideal temperature for the Reckless Medaka is 18〜28℃.
Basic Info
Origin
Japan (domestic variety created in 2021 by Mai Medaka)
Lifespan
Care Specifications
- pH
- 7–8
- Hardness (GH)
- 9–19 dGH
- Water Temp.
- 18–28℃
PeacefulGroupBreeding: Moderate
Sources: Medaka Web Encyclopedia: Complete Medaka Care Guide / FishBase Oryzias latipes / Medaka Web Encyclopedia No.0871
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
Yellow body colourSemi-transparent scale (aurora)Lame (glitter scales)Hirenaga (all-fin elongation)
Sources: Japan Medaka Association: Variety Classification Manual, 5th ed. (Sep 2025) / Medaka Web Encyclopedia: Medaka Traits / Medaka Web Encyclopedia No.0871
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.0871
- 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: 舞めだか (2021)
Authority databases: FishBase · GBIF · Medaka Web Encyclopedia No.0871
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.
Reckless Medaka Listings
Loading latest listingsFind listings for this species
