Sri Lanka is a tropical island situated close to the southern tip of India. The invertebrate fauna is as large as it is common to other regions of the world. There are about 2 million species of arthropods found in the world, and still it is counting. So many new species are discover up to this time also. So it is very complicated and difficult to summarize the exact number of species found within a certain region.
This a list of the pteridophytes found from Sri Lanka.
Pteridophytes
Pteridophytes are vascular plants which reproduce by spores. These free sporing vascular plants show a remarkable life cycle with independent gametophyte and sporophyte generations. Pteridophytes are composed of ferns and lycophytes. Ferns consist of stems, leaves and roots. The stem is usually referred to as rhizome, which is sometimes underground in nature. Most species show stolons and few are with semi-woody trunks. Leaves are referred to as a frond. New leaves typically expand by the unrolling of a tight spiral, the phenomenon known as circinate vernation.[1] There are about 10,560 known species of ferns in the world.[2]
Lycopods are belong to the division Lycopodiophyta, and some are homosporous while others are heterosporous. They differ from ferns due to presence of microphylls, which are the leaves that have only a single vascular trace. There are two extant classes of lycopods, which contains a total of 12 genera and 1290 known species.
The earliest notes on pteridophyte diversity of Sri Lanka dated back to 1887 with Baker's Handbook to the Fern Allies and then in 1892 with Beddome's Handbook to the Ferns of British India, Ceylon, and the Malay Peninsula. In 1947, Copeland adopted a taxonomical system to describe modern taxa of pteridophytes of Sri Lanka. Based on these publications, Prof. R.N. de Fonseka and Mr. M.A.B Jansen prepared the checklist of the pteidophytes of Sri Lanka in 1978.[3] Since then, many experiments and research were carried out about particular families which are important to economy.[4][5][6][7][8]
The following article is based on the checklist by Fonseka and Jansen in 1978.[9]
