SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd1976336e2ca6396073bf993d66719edf310ac8c42b6a57fc87b35e376567464' 
  AND token = 'u03LEZ8a5gldAE/abdwoIUPjHcxuu2hStkSpSZPBtVU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

Explain
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE Impossible WHERE noticed after reading const tables