SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '36973c6847425e8e2ab741b0a5003691d2be6bfab5bbf67c6be81bd89e7a2c5e' 
  AND token = 'AARTajyx6Qba2D2BGRVr8rHJXbnL3cce+QCuKU0ta58=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

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