Thismia aliasii (Thismiaceae), a new species from Terengganu, Peninsular Malaysia

A new mycoheterotrophic species, <i>Thismiaaliasii</i>, is described and illustrated. This species inhabits a hill dipterocarp forest in mountains of eastern Peninsular Malaysia. <i>Thismiaaliasii</i> differs from other <i>Thismia</i> species by the following features: tepals equal in size and shape with different length of their appendages, appendages of the outer tepals shorter than those of the inner tepals (3.5 mm vs. ca. 26-32 mm long), stamen supraconnective at apex with three long filiform appendages and two acute appendages, and the margins of individual connectives abaxially raised into a conspicuous rib. With respect to floral morphology, <i>T.aliasii</i> should be placed to Thismiasubsect.Odoardoa. According to the categories and criteria of the IUCN Red List, <i>T.aliasii</i> is provisionally classified as Critically Endangered (CR).