SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a9ab3d6991a6d0bfbfd66bd18244e928eb3577a916a12b79fc7640fa984fc50c' 
  AND token = 'aGOudc5mKZqiYyXuJeWa+IN0aqBkkJn2JUpeLCcG8Pw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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