SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '303ba3b1dcf2dd327ddfb99982bed48258d3aa32127812a8f08fb9ce16480362' 
  AND token = '0DoGXtgBjiTTupkMGAPm6RPNUWx1Vo1McW0YNc5SZEc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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