SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9830b05c0e0cb21bebda901bb368cc2e191008d724c2797602997c7739bdf574' 
  AND token = 'mi9HEZTpdWoawaJmQZEHy6hHYFry2y3BzpYAHVGPaYc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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