SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aa020a15d57cd0e7c24d2281f37782732031ea3617991229783b01001f585295' 
  AND token = '4DwC0pRYWdtLb/hPvJPtowqDH30PTsKS8WNHZXWRCEY=' 
  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