Ancestor Corydoras CW004/155
Ancestor Corydoras CW004/155 (Hoplisoma noxium) — known by the collector codes CW004 and CW155 — is a species recently reclassified into the genus Hoplisoma. It displays a pale body with a large, dark, irregular blotch over the dorsal area, giving it a distinctive saddled appearance. The name 'Ancestor' reflects its taxonomic position as an early-described species in the group.
Feeding & Care Tip: Hikari Sinking Wafers make an excellent daily staple and Sera Vipachips Tropical Wafers are an excellent alternative. Supplement 2–3× per week with Hikari Frozen or Freeze-Dried Bloodworms, Hikari Frozen or Freeze-Dried Tubifex Worms. Feed near the substrate at or after lights-out when corydoras are most active.
Native to South America (Colombia and Venezuela). In the aquarium, soft to medium, slightly acidic to neutral water with fine sand substrate, gentle filtration, and shaded areas created by driftwood or plants replicates the natural habitat and produces the most active, healthy behavior.
Keep in groups of at least six — this is not optional for Corydoras. In the wild these fish occur in schools of dozens to hundreds. A lone Corydoras or a group of fewer than six is a stressed fish that stays hidden, refuses food, and lives a shortened life. In a proper group they are bold, constantly active, and endlessly entertaining to watch as they forage together across the bottom of the aquarium.
Corydoras are highly sensitive to substrate quality — fine sand is strongly preferred over gravel, as rough substrates damage the delicate barbels they use to forage. Regular partial water changes and pristine water quality are essential, as all Corydoras are sensitive to nitrites and dissolved waste. Sand substrate, gentle flow, and shaded areas with driftwood or plants will keep this species at its happiest and most active.
Care & Ideal Parameters
| Difficulty | Easy |
| Temperament | Peaceful — Community |
| Typical Adult Size | 3.0 inches (7.5 cm) |
| Min. Group Size | 6 minimum — groups of 8+ for best activity |
| Ideal Temp | 72–82°F (22–28°C) |
| Ideal pH | 6.0–7.0 |
| Ideal GH | 0–15 dGH |
| Ideal KH | 0–10 dKH |
| Staple Food | Hikari Sinking Wafers; Sera Vipachips Tropical Wafers |
| Treat / Supplement | Hikari Frozen or Freeze-Dried Bloodworms, Hikari Frozen or Freeze-Dried Tubifex Worms |
| Origin | South America (Colombia and Venezuela) |
| Notes | Genus Hoplisoma — reclassified from Corydoras. CW004/CW155 collector numbers. Large dark dorsal saddle on pale body. Hardy and adaptable. Sand substrate essential. |