SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '94f33b6b3f5c1939be3d4d790c1c96f42195a076294cc76882713a079429cda8' 
  AND token = 'xCwsFcyOHZZ491viLiByuZD1pZ1YxsxItzcADGw24dc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

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