in Sri Lanka - Ministry of Environment

Taxonomy and Conservation Status of Pteridophyte Flora of Sri LankaR.H.G. Ranil and D.K.N.G. PushpakumaraUniversity of PeradeniyaIntroductionThe recorded history of exploration of pteridophytes in Sri Lanka dates back to 1672-1675when Poul Hermann had collected a few fern specimens which were first described by Linneus(1747) in Flora Zeylanica. The majority of Sri Lankan pteridophytes have been collected in the19 th century during the British period and some of them have been published as cataloguesand checklists. However, only Beddome (1863-1883) and Sledge (1950-1954) had conductedsystematic studies and contributed significantly to today’s knowledge on taxonomy and diversityof Sri Lankan pteridophytes (Beddome, 1883; Sledge, 1982). Thereafter, Manton (1953) andManton and Sledge (1954) reported chromosome numbers and some taxonomic issues ofselected Sri Lankan Pteridophytes. Recently, Shaffer-Fehre (2006) has edited the volume 15of the revised handbook to the flora of Ceylon on pteridophyta (Fern and Fern Allies).The local involvement of pteridological studies began with Abeywickrama (1956; 1964;1978), Abeywickrama and Dassanayake (1956); and Abeywickrama and De Fonseka, (1975)with the preparations of checklists of pteridophytes and description of some fern families.Dassanayake (1964), Jayasekara (1996), Jayasekara et al., (1996), Dhanasekera (undated),Fenando (2002), Herat and Rathnayake (2004) and Ranil et al., (2004; 2005; 2006) have alsocontributed to the present knowledge on Pteridophytes in Sri Lanka. However, only recently,Ranil and co workers initiated a detailed study on biology, ecology and variation of tree ferns(Cyatheaceae) in Kanneliya and Sinharaja MAB reserves combining field and laboratorystudies and also taxonomic studies on island-wide Sri Lankan fern flora. As a result, Ranil etal. (2010a; 2010b) have described two new pteridophyte species from Sri Lanka and identifiedconservation priorities for Sri Lankan tree ferns in 2011 (Ranil et al., 2011). Ranil et al.,(in prep.) reviewed and revised the list of endemic pteridophytes in Sri Lanka.Currently, about 348 pteridophyte taxa from 30 families have been recorded from Sri Lanka,of which 50 taxa are reported to be endemic to the country (Shaffer-Fehre, 2006). AmongAsian countries, Sri Lanka is second only to Taiwan in terms of the number of pteridophytespecies per 10,000 km 2 (Ranil et al., 2008a). Geographical isolation, and a wide range ofclimatic, elevational and soil type variation in Sri Lanka may have resulted in rich diversityof pteridophyte flora as well along with exceptionally high level of endemism. It is reportedthat Sri Lankan pteridophytes have strong phyto-geographical relationships with South Indianspecies. Further, both the Sri Lankan and the South Indian pteridophyte flora also have phytogeographicalrelationship with three regions, namely the Sino-Himalayan flora, the Malesianflora from South East Asia, and an African element connected with the Seychelles, Mascarenes,Madagascar and East Africa (Fraser-Jenkins, 1984). Despite historical and recent informationon pteridophyte flora of Sri Lanka, this is the first instance that the pteridophyte flora has beenassessed based on the national Red Listing criteria.148