SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '54549053029115860e32addd989fcd69a8c474266b89ffacad52d84bbbfe41f0' 
  AND token = 'ubJ8j3McfAdOggrPccq6XLnug45kBTkQbpnDu0+/sew=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

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