SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd4b50506db1206a227a825cf7adbd4de64ea452cbeb371993892706ef781d320' 
  AND token = 'NJL3cLqiSajFu+j5dM9XwC42YxxZ+WixWh7Imo+0x5c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

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