SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '01c9730526c367dd76cd3bb28755bc358207f9da5b796d0a3c7538239fe34011' 
  AND token = 'fC9TXqYzn4RrJn6OvhkYZhhJg8O1KDQbFIeUTBnSrYQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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