SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1280db91def9fccf4e6bb996af7dacfae7005b36b09953800025c1a87c412dda' 
  AND token = 'n/FABiJL+gbn785jZDEyLGK38B2ct76LzBf6Gww4chs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}