×

Cookie Settings

This website uses different types of cookies to enhance your experience. Please select your preferences below:

Strictly Necessary

These cookies are essential for the website to function properly. They include session cookies, which help maintain your session while you navigate the site, as well as cookies that remember your language preferences and other essential functionalities. Without these cookies, certain features of the website cannot be provided.

Performance

These cookies help us understand how visitors interact with our website by collecting and reporting information anonymously. For example, we use Google Analytics to generate web statistics, which helps us improve our website's performance and user experience. These cookies may track information such as the pages visited, time spent on the site, and any errors encountered.

Save and Close

Distribution: Circumglobal. Uncommon in most areas but abundant around isolated oceanic islands (Ref. 9710).

How to read the map

The literature species report in a territory is represented by an icon (a circle) in the middle of the territory polygon.
Important: a report in the literature does not necessarily mean that the species is currently present in the territory! There are errors in literature, misidentifications, and some species have been locally or globally extirpated or eradicated.

The patterns and colours of the icon give 4 additional indications (see the legend under the map for the signification of the different colours and patterns):

• Presence status: the colour of the ring (green: Present; orange: Possible; red: Absent)
• Introduction status: a white 'i' in the middle of the circle indicates that the species has been introduced, if the presence ring is green it means that the species established itself or that we don't know the current presence status, if the presence ring is red it means that the species did not established itself.
• Threat status: the pattern of the ring (not dashed: not threatened or no information; dashed: any status indicating that the species has a national threatened).
  Important: This is the national threatened status, not the global IUCN one.
• Salinity status = milieu: the colours in the middle circle (blue: Marine; green: Brackish; light blue: freshwater; dark green: Land).

How to interpret the map

• The icon in a territory polygon indicates that the species has been reported at least once in the territory, BUT NOT NECESSARILY that it is present IN THE ENTIRE TERRITORY.
• It is particularly the case for large territory such as Brazil, USA, Canada, Russia, China, India, Indonesia, Australia, etc.
• For example, a number of freshwater species present in western European territories are also present in the western part of Russia, but not beyond the Ural mountains. Still the icon for Russia is placed in its Asian part.
• The icon is placed approximately in the middle of the territory, even for the species that are marine only.
• For marine species, it does not mean either that the species is present in all oceanic coasts of the territories (e.g., Altlantic and Pacific for USA and Canada).
• So the map needs to be interpreted carefully, but we think it helps to give a quick view of the distribution by territory, in a better way than the textual list of territories when it is over a dozen territories.

The map in this page was supported by BioFresh that has received funding from the
European Union's Seventh Programme for research, technological development and demonstration under grant agreement No 226874