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Oryzias latipes var.
Medaka with elongated dorsal, caudal, and pectoral fins. Developed by Matsui fish farm. Gracefully flowing fins are best appreciated from the side.
Matsui Hirenaga medaka is a long-finned improved variety developed by Matsui Fish Farm in Okayama Prefecture, with all fins — dorsal, caudal, pectoral, and ventral — elongated beyond normal. Unlike the swallow-tail trait, all fins are uniformly extended, creating gracefully flowing fin movement best appreciated in side-view aquariums. Long-fin trait is highly heritable. Strong water flow is the primary care concern — it damages delicate fins and increases bacterial fin rot risk; sponge filters providing gentle current are essential. Hardy in 5–30°C, neutral to slightly alkaline water. Exists in many combinations including Miyuki Hirenaga and Youkihi Hirenaga.
Origin
Japan (selectively bred variety)
Lifespan
1-3 years
Size
3-4cm
Temperature
5〜30℃
Medaka pellets, daphnia
Side-view tank to enjoy fin beauty
Keep flow gentle to reduce strain on long fins
5-30°C (optimal 20-28°C)
Sources: FishBase: Oryzias latipes / Seriously Fish: Oryzias latipes
改良メダカは体型×体色×柄×光(体内/体外)×鱗(透明鱗)×ラメ×ヒレ等のトレイト合成。掲載は当該品種を構成する確証トレイトのみで遺伝形式は確証のみ付与(不確実は省略)。遺伝形式は交配の参考。
Sources: JMA日本メダカ協会 改良メダカ品種分類マニュアル / 改良メダカWEB図鑑(medakazukan)
A curated selection of notable morphs. Inheritance modes are a breeding-planning guide; actual appearance varies with combos.
Edited & verified by: br-choku editorial team
The taxonomic, regulatory, and husbandry data on this page are compiled and verified against the authoritative primary sources below.
Accepted name: Oryzias latipes var. (Temminck & Schlegel, 1846)
Synonyms: Aplocheilus latipes (Temminck & Schlegel, 1846), Poecilia latipes Temminck & Schlegel, 1846, Oryzias latipes latipes (Temminck & Schlegel, 1846)
Authority databases: FishBase · GBIF · 日本メダカ協会 品種分類マニュアル
Nomenclature follows global taxonomic authority databases.
Find listings for this species
Long fin x long fin crosses improve fin length in offspring
Fins easily damaged — reduce aquascape decorations
Intermediate. This is an intermediate-level species. Some prior experience and knowledge of environmental management are recommended.
The ideal temperature for Matsui Hirenaga Medaka is 5〜30℃. Avoid sudden temperature changes and maintain a stable environment.
The average lifespan of Matsui Hirenaga Medaka is 1-3 years. With proper care and nutrition, they can live a long and healthy life.
Matsui Hirenaga Medaka typically reaches 3-4cm as an adult. Size may vary depending on care conditions and individual genetics.
Matsui Hirenaga Medaka feeds on: Medaka pellets, daphnia. Aim for a balanced diet with appropriate feeding frequency.
The price of Matsui Hirenaga Medaka varies significantly depending on morph, size, and lineage. Check our market price page for the latest pricing information.
Last updated: July 8, 2026