Lichenized fungi

A lichen is a symbiotic organism composed of a fungus and an algae or cyanobacteria (in some cases both). This relationship has enabled lichenized fungi to inhabit most terrestrial habitats, including some that are too stressful for most other organisms (e.g., high altitudes, high latitudes, and early succession sites following disturbances such as landslides). Nearly 50% of all reported Ascomycetes are lichenized. The world-wide diversity of lichenized fungi is among the best known for any group of fungi. Nevertheless, much more work surveying tropical diversity is necessary.

Dictyonema glabratum

Protocols:

Lichenized fungi will be collected and processed following the protocols provided by Dr. Harrie Sipman during the short course on lichens given in November, 1999.

Sampling lichen diversity:

Lichens will only be collected during the dry season (January - April). Sampling will begin in January 2000.

1. Sample the transects set out for macrofungi. If possible, tree canopies should be investigated by climbing.

2. Sample all trees and shrubs in an area of 10m on both sides of a transect set out along 50 m of a forest trail. One usually does not have to resample a site since the lichen community does not change rapidly and since they are always present. Therefore, choose a different trails to sample each year. Do as many of such trail plots as time permits, preferably on in each principal vegetation type.

3. The plot inventories should be combined with visits to rocky, open, or swampy sites, and with a search for particularly large trees of various species to cover microhabitat groups that are too sporadic to be included in plots. Do as time permits during the dry season. In the first year the inventory will concentrate on macrolichens. The other groups will be added to the inventory in subsequent years.

Protocols for documenting and preserving fungi in the field:

1. Collection data for all specimens will be entered into a database on laptop computers. This database will be compatible with ATTA and will enable ready transfer to that web accessible system.

2. Fresh material of lichenized fungi is not needed for cultures. On dry, sunny sites the specimens can be placed in the sun for drying, provided they are not too bulky and are in paper packets. Under humid conditions a dryer of the same type as used for the other fungi can be used. As a rule, specimens should be dry within two days. Thick pieces of bark dry slowly and need special attention. Photographs of fresh specimens or specimen descriptions are usually not required as only a few species from shady sites show a significant color change after drying, the rest remain unchanged. Lichens on leaves are sampled by collecting whole leaves and treating them like higher plants: they have to be pressed between papers. Avoid excessive heat and conservation liquids like alcohol or formalin. The leaves should not be kept in plastic bags for a long time before putting them in the press. Examination by stereomicroscope can help to separate mixed samples that are often inadvertently made in the field.

Protocols for identifying and curating the collections:

Identification of lichenized fungi is based on macro- and micromorphological characters as well as thin layer chromatography (TLC). Curators and technicians will use compound and stereo microscopes equipped with digital image capture systems to facilitate capturing images for documentation, rapidly sharing information with international collaborators through e-mail, publications and other products. International collaborators will perform TLC on the groups that they specialize in.

Plot based inventories tend to generate large number of specimens, and an accession policy is mandatory to prevent a herbarium from being overwhelmed (both in processing time and space) by redundant collections. In general, it is recommended that 2 or 3 good samples of each taxon from each site be retained. Common or poorly represented species may be vouchered by small fragments included as addition in other samples from the same microhabitat. The collection database should have the capacity to retrieve such additions.