AVH Public Help Page

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Introduction

The Australia's Virtual Herbarium (AVH) portal allows users to access herbarium specimen information from all Australian Commonwealth, state and territory herbaria with a single query. Data returned by the AVH portal is presented to the user as it is delivered to AVH by the participating herbaria, including uncertainties and errors, and should be checked for accuracy and precision before use.

The most common errors in AVH data arise from the misidentification of specimens or incorrect locality geocodes. Much of the data provided through AVH has been acquired for use in plant taxonomy and systematics and, while suitable for these purposes, may not be suitable for applications that require higher levels of precision. Data is continually tested and improved at the herbaria, and is regularly updated in AVH. The contributing herbaria appreciate feedback on any errors or discrepancies detected in the data.

It is important to bear in mind that different herbaria store their collection data in different ways. Furthermore, different herbaria, and indeed botanists in the same herbarium, delimit certain taxa in different ways. Therefore, queries will often return surprising results and it will not always be possible to get all the data the user is after with one query.

The information on this page is intended to assist users in understanding the limitations of AVH data and to achieve the best query results.

Query form

General

AVH search terms are case insensitive: 'Banksia' and 'banksia' will return the same records.

The wildcard is '%'. 'alb%' will return 'alba', 'album', 'albida', 'albidum', 'albescens', 'albertensis' etc. The wildcard can be placed anywhere in the search value to make the desired pattern. A wildcard at the start of a query value will significantly slow down a search and may result in the query timing out.

Navigating the query form

The query form works best with Javascript enabled, but will also work without. The following assumes that Javascript is enabled.

The query form has an expandable form for querying taxon names. Typing a genus name in the taxon name query will bring up a plus-sign button. Clicking on the button or hitting <ENTER> when it is in focus will add a new row. Up to five taxon names can be entered.

Taxonomy

Taxon name

You can query up to five taxon names at a time. Note that different herbaria may delimit certain taxa in different ways, so you may need to also query on synonyms in order to retrieve all records of a taxon. For example, some herbaria still recognise the genus Dryandra, while in other herbaria Dryandra is merged with Banksia. So, for instance, if you want to retrieve all records of the species Banksia armata (or Dryandra armata as the case may be), you should include both names in your query.

The following resources provide authoritative information on plant names and synonymy:

The Australian Plant Census (APC) is a cooperative project under the auspices of the Council of Heads of Australasian Herbaria (CHAH). The APC will provide a compromise view of Australian taxa, as well as an overview of different taxonomies and full synonymies. Once completed, an APC-based name service will be incorporated in AVH, allowing users to search for records of taxa without having to query for multiple names.

Uncertain identifications

Tick this box to include uncertain identifications in your query result. Uncertain identifications are excluded by default. Please note that not all herbaria provide this information. Therefore, query results may contain some uncertain identifications whether or not uncertain identifications have been explicitly included.

Output

Map

Mapping specimen records can provide a good overview of species' distributions. Only georeferenced records are shown on maps; to access non-geocoded records, choose another output format. The number of records from each herbarium is displayed in the top right of the screen. Note that these numbers include records that do not have latitude and longitude recorded. Click on the 'Redraw map' button after changing any display options. Clicking on 'New query' will take you back to the query page.

If the legend has more than one item, you can turn individual layers on and off. The map and legend can be downloaded in various formats.

You can open an overview map by clicking on the arrow in the lower right corner of the map. Clicking anywhere in the overview map will reposition the map. Clicking on the arrow in the overview map will close the overview map.

Boxes can be dragged to different positions, and minimised and then restored. The legend and query boxes can be resized as well. Clicking on the 'Reset boxes' button will return all elements to their original position. Note that the 'Reset boxes' button will only appear after you have moved, resized or minimised a box.

The results can be grouped in different ways:

  • By species – if more than one species is mapped, each species is displayed with a different symbol.
  • By taxon – if more than one taxon is mapped, each species or infraspecific taxon is displayed with a different symbol.
  • By herbarium – records from different herbaria are displayed with a different symbol.
  • By precision – records are displayed according to the precision assigned to the latitude and longitude.
  • Use single symbol – all records are displayed with the same symbol.

You can select one of the following options:

  • Show specimen information – the specimen data associated with the record will be displayed in a separate window.
  • Pan – click on the map (don't drag it) to reposition.
  • Zoom out – click on the map to zoom out by the factor entered under zoom factor.
  • Zoom in – click on the map to zoom in by the factor entered under zoom factor.

The following layers can be displayed on the map. The terrain, temperature and rainfall layers cannot be displayed together.

  • Terrain – general terrain features developed by Geoscience Australia, National Mapping Division. This layer is not available when zooming in at higher magnifications.
  • Temperature – mean annual maximum temperature isotherms from base climatological data sets supplied by the Bureau of Meteorology.
  • Rainfall – mean annual rainfall isohyets from base climatological data sets supplied by the Bureau of Meteorology.
  • States – state and territory borders, derived from Global Map Data Australia 1M 2001 developed by Geoscience Australia, National Mapping Division.
  • IBRA regions – the Interim Biogeographic Regionalisation of Australia regions, which categorise the Australian continent into regions with similar geology, landform, climate, vegetation and fauna.
  • 10° graticule – latitude and longitude grid at 10° intervals.

HTML table

You can choose to display 10, 25, 50 or 100 records per page. Use the navigation buttons at the right of the table header to move through the results pages. The scroll bar at the bottom of the table allows you to view the fields that don't fit within the table window.

By default, your query results will be ordered by herbarium and accession number. The data can be sorted by clicking on the arrows next to the column. Click on the arrows once to sort the results in ascending order; click twice to sort in descending order. You can sort on up to three columns at once by holding the <SHIFT> key while selecting the second and third columns.

Note that, because some accession numbers include letters, the accession numbers are treated as text and can not be ordered numerically.