Thismia belumensis (Thismiaceae), a remarkable new species from The Royal Belum State Park, Gerik, Perak, Peninsular Malaysia.

Mat Yunoh Siti-Munirah,Zainol Suhaimi-Miloko,Mohammad Ismail Zubir Ahmad

doi:10.3897/phytokeys.172.59336

Abstract

This report describes Thismia belumensis Siti-Munirah & Suhaimi-Miloko, a novel species of achlorophyllous herb discovered in the Royal Belum State Park, Peninsular Malaysia. This new species is unlike any previously described species of Thismia. In particular, T. belumensis possesses a unique annulus, which has been expanded and modified into a cucullate (hood-like) structure. This structure covers the apical floral tube and has an opening on one side facing a thickened part of the annulus, and the off-centre floral aperture confers a zygomorphic symmetry to the flower, indicating T. belumensis is more similar to Thismia labiata J.J.Sm. This morphological detail makes this new species distinct from all other described species of Thismia. In this report, we provide descriptions, illustrations, colour plates, and the provisional conservation status of Thismia belumensis.

Highlights

Thismia Griff. (Thismiaceae) is a genus of small mycoheterotrophic herbs, currently comprising approximately 80–90 species (Dančák et al 2020a; Nuraliev et al 2020; Shepeleva et al 2020)
Throughout Malaysia, there are currently approximately 30 Thismia species, of which – including T. belumensis, described in this report, – 14 of these are found in Peninsular Malaysia
This report represents the first description of a novel, notable, and very rare plant – T. belumensis – from The Royal Belum State Park (SP), Perak, Malaysia. This new species is significantly different from other “fairy lantern” species found in the Malay Peninsula and Borneo

Summary

Introduction

Thismia Griff. (Thismiaceae) is a genus of small mycoheterotrophic herbs, currently comprising approximately 80–90 species (Dančák et al 2020a; Nuraliev et al 2020; Shepeleva et al 2020). Throughout Malaysia, there are currently approximately 30 Thismia species, of which – including T. belumensis, described in this report, – 14 of these are found in Peninsular Malaysia These are: Thismia alba Holttum ex Jonker, Thismia arachnites Ridl., Thismia aseroe Becc., Thismia chrysops Ridl., Thismia clavigera F. The Thismia species described here was first discovered in 2017 by Mr SuhaimiMiloko during a guided nature tour in the Royal Belum State Park (SP), Perak, Peninsular Malaysia (Map 1). The new species of Thismia was discovered in the Sungai Gadong forest area, in the southern part of the Royal Belum SP This location is an important habitat of Rafflesia azlanii Latiff & Wong, and R. cantleyi Solms, which possess the world’s largest. Some novel characteristics of the annulus and tepals were identified in the specimens These traits formed a unique combination of characteristics that did not match any described species of Thismia.

Materials and methods

Discussion