Stichodactyla haddoni differences

Paleozoic_reefer · Mar 26, 2026

@Beuchat and @OrionN I recently acquired a second Stichodactyla haddoni and noticed a difference in the shape of the tentacles and shape of the bodies between my current blue haddoni and the new one. Is there a reason for the difference? I’m assuming they are both haddonis but with different characteristics. Any insight is greatly appreciated!

D-Nak · Mar 27, 2026

Looks like the green one is still acclimating. Oftentimes the white blotches or stripes go away as the haddoni settles in. The tentacles may change shape as well, more closely resembling that you see on your blue haddoni. That said, all haddoni may react slightly differently to their environment--changes in lighting and flow may cause the tentacles to remain short and tight, but also loosen and lengthen.

Paleozoic_reefer · Mar 27, 2026

D-Nak said:
Looks like the green one is still acclimating. Oftentimes the white blotches or stripes go away as the haddoni settles in. The tentacles may change shape as well, more closely resembling that you see on your blue haddoni. That said, all haddoni may react slightly differently to their environment--changes in lighting and flow may cause the tentacles to remain short and tight, but also loosen and lengthen.

Thanks @D-Nak! I’m new to haddonis so any information is appreciated.

Beuchat · Mar 28, 2026

Paleozoic_reefer said:
@Beuchat and @OrionN I recently acquired a second Stichodactyla haddoni and noticed a difference in the shape of the tentacles and shape of the bodies between my current blue haddoni and the new one. Is there a reason for the difference? I’m assuming they are both haddonis but with different characteristics. Any insight is greatly appreciated!

Hi,

The tentacle length varies due to a combination of genetics and environmental factors. Specimens of the same species have different genes, according to their evolutionary history (for example, the place of origin of recent generations).Genetic differences set the baseline structure, while lighting plays a major role: stronger light leads to shorter, compact tentacles, whereas lower light encourages elongation. Water flow also influences shape, with stronger currents causing tentacles to stay shorter or more retracted. Adequate feeding results in fuller, more turgid tentacles, while poor nutrition leads to thinner ones.