SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b9c05bdd003e66d998bdc3a11503d6448be182e3aa87a997481b1acb505e5a9d' 
  AND token = '87Tft3fTisTIYU/3NPCHMB3cW8bua8STJY+sL0M99O0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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