SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd2d1aa5e27aa770f1b9bdbc0186308140302ea3b122f91b800c38abd7b4456de' 
  AND token = 'QGVVFBZPUCCzPp56uXZKvd/JiKmFWkWpD0pYhmRr9xg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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