SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fd23a8f4acc8ddb64a67fcfd0725145f3136930b6933338fc66b661357b740e9' 
  AND token = 'Us/n43EzDj8LsNNmjYYVRcl0AhYZ9HOAgnJXacuG67w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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