Thismia taiwanensis sp. nov. (Burmanniaceae tribe Thismieae): First Record of the Tribe in China

Abstract

A new holomycotrophic species, Thismia taiwanensis (Burmanniaceae), is described and illustrated from Kaohsiung County, south-central Taiwan. It most closely resembles the Japanese species T. abei and T. tuberculata, but is distinct as the flowers are subsessile, the outer surface of the perianth tube is smooth, the outer tepals bear very short solitary appendages, and the inner tepals bear longer solitary appendages. This represents the first record of both Thismia and Burmanniaceae tribe Thismieae in China. The genus Thismia Griff. (Burmanniaceae) consists of ca. 35 species of small holomycotrophic herbs, typ- ically growing amongst leaf litter on the forest floor. The only comprehensive taxonomic monograph of the genus was published by Jonker (1938), who recognized 23 species in Thismia itself, as well as several other genera that have been subsequently reduced to syn- onymy with it, viz. Glaziocharis Taub. ex Warm. (one species), Triscyphus Taub. ex Warm. (one species), Geomitra Becc. (one species), and Scaphiophora Schltr. (two species). Jonker (1938) proposed a supraspecific classification system for Thismia, with five sections. This classifica- tion was necessarily reassessed following the accep- tance of a broader generic concept for Thismia: Hatu- sima (1976), for example, established Thismia sect. Gla- ziocharis (Taub. ex Warm.) Hatusima following the re- duction of Glaziocharis into synonymy with Thismia. Maas et al. (1986) recently proposed a comprehensive subgeneric and sectional classification for the neotrop- ical members of the genus, with several new taxa that were previously recognized as distinct genera. Although Thismia has an essentially pantropical distribution, several species have been described from warm temperate regions. In Asia, the genus extends northwards into southern Japan: T. abei (Akasawa) Ha- tusima (syn. Glaziocharis abei Akasawa) has been re- corded from Honshu, Shikoku, and Kyushu (Akasawa 1950; Shin 1974, as ''Glaziocharis sp.''; Matsumoto and Yamada 1994), and T. tuberculata Hatusima has been recorded from Kyushu (Shin 1974; Hatusima 1976). A new species of Thismia was recently collected in Kaohsiung County in south-central Taiwan; this rep- resents the first record of the genus in China. The spe- cies is formally named and described here as T. tai- wanensis S.-Z. Yang, R. M. K. Saunders & C.-J. Hsu. T