SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '175e25707a7f2cbd7bd69e972b26302d3cca9919dafdd7419c8c7a8e3af3e4bb' 
  AND token = '5CFq/+lYf/XnADx679vI4X0ZJAvmKJhM3VjOVwUYbNo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}