Food refusal
A sudden refusal of prey is common before a moult in Omothymus violaceopes, especially when the spider had been feeding normally beforehand.
Remove ignored live prey from the Singapore Blue Tarantula enclosure instead of offering another feeder immediately.
Retreat use and webbing
Omothymus violaceopes may spend more time hidden, close a burrow entrance or lay heavier webbing before moulting. Leave the retreat intact.
Do not dig out a Singapore Blue Tarantula simply because it has sealed itself in. Retreat closure can be normal premoult behaviour.
Abdomen changes
In species where the abdomen is visible, Omothymus violaceopes may show a darker exposed patch or other colour change as a new exoskeleton develops underneath.
Not every Singapore Blue Tarantula shows an obvious visual change, so use abdomen appearance alongside appetite and behaviour rather than as the only sign.
What to do
When premoult looks likely in Omothymus violaceopes, remove live prey, keep fresh water available and keep the enclosure within its normal moisture and temperature range.
Do not increase handling, spraying or enclosure disturbance for a Singapore Blue Tarantula. Stable conditions and patience are normally what the spider needs.
How long can premoult last?
Premoult in Omothymus violaceopes can last much longer in a large animal than in a tiny sling. The passage of time alone does not prove something is wrong.
Judge a Singapore Blue Tarantula by overall condition and enclosure access to water, not by expecting every spider to moult on the same timetable.