How to use LIASlight NaviKey

I) Recommended characters

Characters recommended to be used during first identification steps are those which can be objectified most easily and are therefore also included a) in most species descriptions and b) in traditional dichotomous keys.

In lichens most reliable characters proferably concern

1) Biological/ecological characters:

a) Primary and secondary photobionts: presence and major types

b) Substrate: major types

2) Morphological characters:

a) Specific characters of the upper and lower thallus surface: e. g. cilia, isidia, soredia and rhizomorph-like structures

b) Structure of the teleomorphic state: major morphological ascoma types

c) Spore characters of the anamorphic and teleomorphic state: number (per ascus), size, wall pigmentation, wall septation (kind and degree) and - to some extent - perispore development and amyloidity

3) Chemical characters

a) Secondary metabolites: their presence, patterns of combination and concentration


Characters, being reliable only to some degree by various reasons, mostly depend from the subjective estimate of the observer and mainly concern those describing the shape, surface properties, and colour of the upper and lower surface of the thallus.

These characters, which are useful for characterizing the species and therefore may often be of major diagnostic value, should nevertheless be used at later stages of the identification process.

II) Query Options

There are two major options of interest:

1) "Retain items unrecoreded for the selected characters" When enabling this option, all those taxa remain in the lower right panel ("Resulting items") which are (positively) coded for the respective character (state) or do not have an entry, i.e. are unrecorded for that. This means, no taxa will "get lost" due to a character state which has been used in the indentification process, but has not been recorded.

However, in LIASlight many incomplete data sets exist, which makes superfluosly many taxa appear in the panel of "Resulting items". Therefore it is recommended to keep this option deselected and preferably a) select instead "Recommended characters" and b) use the option to select more than one character state (see "Multiple states").

2) "Retain items matching at least one selected state" When this option is enabled, multiple selection of states of one character provides taxa with a positive record for at least one of these states. This corresponds to a "or" matching option, in contrast to the "and" option, which only matches those taxa being recorded for all of the selected states. The latter option is most valid in case that whole patterns of secondary metabolites are queried for.

(Unfortunately NaviKey does not yet provide the possiblity to switch between these two query modes between the single steps of the same identification procedure. However this option is going to be implemented in the near future:

III) Multiple states

More than one character state of the same character may be selected by pressing CTRL plus the respective character state(s). Depending from the status of the option "Retain items matching at least one selected state" the list of "Resulting items" provides different results (see there).

IV) Supplementary data

Additional information for a taxon is accessible through a context menue that is shown by clicking the right mouse button on any item in the bottom right panel ("Resulting items"). The evoked context menu provides a list of sources with access to lichen images, taxonomic information, and other kinds of information. Images from reliable sources are available as well, if the button is highlighted in green.