SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eea36390570102be3db0c33ddddd93166fb105deda7f6434009c59407e58ec93' 
  AND token = '0RaOLIljeF484gZvlgU9O+t7nhFUsI1L84yboNSzuW0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00054

JSON explain

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