SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e41738cd9e8016fa1ed239d61fe955a074cfaf055d4a5e1cd39a90f69e5bc621' 
  AND token = 'AdfC+BFoXRdi6IAvvpOE0ClOG6zlP+EZ/SY11ptII34=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

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