Cladonia perforata
Encyclopedia
Cladonia perforata is a rare species of lichen
Lichen
Lichens are composite organisms consisting of a symbiotic organism composed of a fungus with a photosynthetic partner , usually either a green alga or cyanobacterium...

 known by the common names Florida perforate cladonia and Florida perforate reindeer lichen. It is endemic to the state of Florida
Florida
Florida is a state in the southeastern United States, located on the nation's Atlantic and Gulf coasts. It is bordered to the west by the Gulf of Mexico, to the north by Alabama and Georgia and to the east by the Atlantic Ocean. With a population of 18,801,310 as measured by the 2010 census, it...

 in the United States, where it is known from 16 populations in four widely separated areas of the state. It is native to a very specific type of Florida scrub
Florida scrub
Florida scrub is an endangered temperate coniferous forest ecoregion of the state of Florida in the United States. It is found on coastal and inland sand ridges and is characterized by a xeromorphic plant community dominated by shrubs and dwarf oaks. Scrub soils, a type of entisol, are derived...

 habitat which is increasingly rare and patchy due to habitat destruction
Habitat destruction
Habitat destruction is the process in which natural habitat is rendered functionally unable to support the species present. In this process, the organisms that previously used the site are displaced or destroyed, reducing biodiversity. Habitat destruction by human activity mainly for the purpose of...

, degradation, and fragmentation
Habitat fragmentation
Habitat fragmentation as the name implies, describes the emergence of discontinuities in an organism's preferred environment , causing population fragmentation...

. In 1993 this was the first species of lichen to be federally listed as an endangered species
Endangered species
An endangered species is a population of organisms which is at risk of becoming extinct because it is either few in numbers, or threatened by changing environmental or predation parameters...

 of the United States.

Description

This lichen is relatively large, its yellow-gray, slightly glossy fruiting body
Sporocarp (fungi)
In fungi, the sporocarp is a multicellular structure on which spore-producing structures, such as basidia or asci, are borne...

 measuring up to 6 centimetres (2.4 in) in length. The fruiting body, the visible part of the lichen, is a branching, tufted structure. The branches, or podetia, are lined with hypha
Hypha
A hypha is a long, branching filamentous structure of a fungus, and also of unrelated Actinobacteria. In most fungi, hyphae are the main mode of vegetative growth, and are collectively called a mycelium; yeasts are unicellular fungi that do not grow as hyphae.-Structure:A hypha consists of one or...

e on their inner surfaces and are perforated
Perforation
A perforation is a small hole in a thin material or web. There is usually more than one perforation in an organized fashion, where all of the holes are called a perforation...

 with tiny holes. It and similar species undergo vegetative reproduction
Vegetative reproduction
Vegetative reproduction is a form of asexual reproduction in plants. It is a process by which new individuals arise without production of seeds or spores...

 in which it clones
Cloning
Cloning in biology is the process of producing similar populations of genetically identical individuals that occurs in nature when organisms such as bacteria, insects or plants reproduce asexually. Cloning in biotechnology refers to processes used to create copies of DNA fragments , cells , or...

 by physically breaking up and spreading. No sexual reproduction
Sexual reproduction
Sexual reproduction is the creation of a new organism by combining the genetic material of two organisms. There are two main processes during sexual reproduction; they are: meiosis, involving the halving of the number of chromosomes; and fertilization, involving the fusion of two gametes and the...

 has been observed. The lichen's method of biological dispersal
Biological dispersal
Biological dispersal refers to species movement away from an existing population or away from the parent organism. Through simply moving from one habitat patch to another, the dispersal of an individual has consequences not only for individual fitness, but also for population dynamics, population...

 is to have its fragments swept or blown to new locations.

In general, this species is poorly known. Little information is available about its life history, including its precise reproductive cycle, growth, population dynamics
Population dynamics
Population dynamics is the branch of life sciences that studies short-term and long-term changes in the size and age composition of populations, and the biological and environmental processes influencing those changes...

, or any seasonal changes it might experience.

Distribution and habitat

The habitat of this species is the white sand of the Florida scrub, already a rare and endangered type of ecosystem, and the lichen requires a specific spot within the habitat. It can be found on high dune
Dune
In physical geography, a dune is a hill of sand built by wind. Dunes occur in different forms and sizes, formed by interaction with the wind. Most kinds of dunes are longer on the windward side where the sand is pushed up the dune and have a shorter "slip face" in the lee of the wind...

s and ridges among sand pines (Pinus clausa) in the part of the scrub understory
Understory
Understory is the term for the area of a forest which grows at the lowest height level below the forest canopy. Plants in the understory consist of a mixture of seedlings and saplings of canopy trees together with understory shrubs and herbs...

 called "rosemary balds": land dominated by Florida rosemary
Ceratiola ericoides
The Sandhill-rosemary, Florida-rosemary or Sand heath, Ceratiola ericoides, is a shrub usually included in the plant family Ericaceae, though treated by some botanists in the Empetraceae....

 (Ceratiola ericoides). The lichen occurs in very dry, open sites on sand with little plant cover around it. It can often be found tangled up in clumps with other species of lichen.

It is difficult to estimate the abundance of this species. Much of the current data is outdated. The organism in question is often small and sometimes hard to spot on the ground or in the leaf litter. Furthermore, what constitutes one individual organism is not always apparent; one living lichen may be several centimeters long or just a tiny fragment. Populations fluctuate often, occurrences are destroyed, and several new ones have been discovered and rediscovered in recent years. The species was first discovered in 1945 on Eglin Air Force Base
Eglin Air Force Base
Eglin Air Force Base is a United States Air Force base located approximately 3 miles southwest of Valparaiso, Florida in Okaloosa County....

 property on Santa Rosa Island
Santa Rosa Island, Florida
Santa Rosa Island[p] is a 40-mile barrier island located in the U.S. state of Florida, thirty miles east of the Alabama state border...

 near Pensacola
Pensacola, Florida
Pensacola is the westernmost city in the Florida Panhandle and the county seat of Escambia County, Florida, United States of America. As of the 2000 census, the city had a total population of 56,255 and as of 2009, the estimated population was 53,752...

. This, the lichen's type locality, was later paved and the population presumably destroyed. A population was rediscovered in this area of the Florida Panhandle
Florida Panhandle
The Florida Panhandle, an informal, unofficial term for the northwestern part of Florida, is a strip of land roughly 200 miles long and 50 to 100 miles wide , lying between Alabama on the north and the west, Georgia also on the north, and the Gulf of Mexico to the south. Its eastern boundary is...

 in 1989. The species has a disjunct distribution
Disjunct distribution
In biology, a taxon with a disjunct distribution is one that has two or more groups that are related but widely separated from each other geographically...

: the other populations are located on the east and west coasts of the main peninsula of Florida.

Conservation concerns

Threats to this species include development of its habitat for residential, agricultural
Agriculture
Agriculture is the cultivation of animals, plants, fungi and other life forms for food, fiber, and other products used to sustain life. Agriculture was the key implement in the rise of sedentary human civilization, whereby farming of domesticated species created food surpluses that nurtured the...

, and commercial use, pollution and trash dumping, off-road vehicle
Off-road vehicle
An off-road vehicle is considered to be any type of vehicle which is capable of driving on and off paved or gravel surface. It is generally characterized by having large tires with deep, open treads, a flexible suspension, or even caterpillar tracks...

 use, trampling and crushing by people, animals, and vehicles, and severe storms and wildfire
Wildfire
A wildfire is any uncontrolled fire in combustible vegetation that occurs in the countryside or a wilderness area. Other names such as brush fire, bushfire, forest fire, desert fire, grass fire, hill fire, squirrel fire, vegetation fire, veldfire, and wilkjjofire may be used to describe the same...

s. Natural processes such as hurricanes and fires are necessary for maintaining habitat such as Florida scrub, but these events do kill the lichen by burning it, crushing it to small pieces, sweeping it away in storm surge
Storm surge
A storm surge is an offshore rise of water associated with a low pressure weather system, typically tropical cyclones and strong extratropical cyclones. Storm surges are caused primarily by high winds pushing on the ocean's surface. The wind causes the water to pile up higher than the ordinary sea...

s, or burying it in sand. Hurricane Opal
Hurricane Opal
Hurricane Opal was a Category 4 hurricane that formed in the Gulf of Mexico in September 1995.Opal was the ninth hurricane and the strongest of the abnormally active 1995 Atlantic hurricane season...

 in 1995, for example, destroyed at least two known occurrences of the lichen. Lichen rescue operations are sometimes performed in the days after a hurricane in an effort to unbury individuals from sand and debris, and even pluck them out of trees where they have landed. Some individuals are collected on beds of sand and brought indoors when storms are expected. Even if the lichen itself is undamaged in a storm, parts of its rare, limited potential habitat may be rendered unsuitable by disturbances.

The lichen is also vulnerable because it is slow-growing, slow to recover after mortality, inefficient in its dispersal, and already rare with unstable populations. Its patchy, fragmented distribution makes it likely to experience isolation and extirpation
Local extinction
Local extinction, also known as extirpation, is the condition of a species which ceases to exist in the chosen geographic area of study, though it still exists elsewhere...

 of small populations. Since most populations are just clusters of clones, each population is extremely valuable in the conservation of the species. The populations occur in North, Central, and South Florida, and can be separated by hundreds of miles; gene flow
Gene flow
In population genetics, gene flow is the transfer of alleles of genes from one population to another.Migration into or out of a population may be responsible for a marked change in allele frequencies...

between them is often highly unlikely.

New populations have been reintroduced to appropriate habitat where the species has been observed before. Many populations are located in areas that are protected from development and fragmentation. At last review the species was still considered endangered.
The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK