&lt;i&gt;Stenochlaena riauensis&lt;/i&gt; (Blechnaceae), a new fern species from Riau, Indonesia

Andesba A Roza,Dr Fitmawati,Dyah Iriani,Nery Sofiyanti

doi:10.3329/bjpt.v22i2.26075

Abstract

Stenochlaena riauensis, a new fern species from Riau, Indonesia is described and illustrated. This species can be distinguished from its most closely related species S. palustris by the position of fertile and sterile pinnae. In the new species, both fertile and sterile pinnae are located on the same frond, the lower part of lamina consisted of sterile pinnae that gradually narrower towards apex forming linear fertile pinnae.Bangladesh J. Plant Taxon. 22(2): 137-141, 2015 (December)

Highlights

During our expedition in Riau Province (Sumatera Island, Indonesia) from 2012 to 2014, we discovered that S. palustris (Burm.f.) Bedd (1876) is the the most widely distributed and abundant fern species in this province (Fig. 1)
Both fertile and sterile pinnae are located in one frond, the lower part of lamina are consisted of sterile pinnae that gradually narrower forming fertile pinnae on the tip of leaves
Fertile pinnae 9 per frond, started from the middle of laminae toward the apex, pinnae gradually reduce towards the apex of lamina, shortly stalked, form elongated fertile pinnae on the tip, usually asymetric at the base, the reduced sterile pinnae glabrous on both surfaces, c. 7 cm long, 1.5 cm wide, blackish green stalk c. 2.0−2.5 mm long, margin serrate, veins anastomosing and forming single row of areoles along each side of costa, at the fertile parts become yellowish green and narrower, linear, the top pinnae is the longest (c. 8 cm long, 2 mm wide), margin curve forming a linear groove at ventral surface

Summary

Introduction

Most of the species of the genus have both sterile and fertile pinnae. Chamber (2013) reported that this genus is strongly dimorphic, in which fertile and sterile pinnae are located at the different fronds, with imparipinnate pinnae. During our expedition in Riau Province (Sumatera Island, Indonesia) from 2012 to 2014, we discovered that S. palustris (Burm.f.) Bedd (1876) is the the most widely distributed and abundant fern species in this province (Fig. 1).

Results

Conclusion