SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c01cd331ede56c250f9b017ea2f722b49bad75445e212726f87de8431ab52f66' 
  AND token = 'RmwY73/xqdP5859jXgO+p0ZDLUyDmk2J8ZPnNI4SFHk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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