SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '650f6bfad5626cf5381c5b53545221ed43f0815f58f49244233f065cd0d6eafa' 
  AND token = '+BpK1ojKAw9QVaRUDTPZ9TDlaiZikSssLB8zU+4PXUA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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