Resolution of the Thelymitra Variegata (Orchidaceae) Complex of Southern Australia and New Zealand
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Resolution of the Thelymitra variegata (Orchidaceae) complex of southern Australia and New Zealand Jeffrey A. Jeanes Royal Botanic Gardens Melbourne, Birdwood Avenue, South Yarra, Victoria 3141, Australia; e-mail: [email protected] Introduction Abstract Thelymitra J.R.Forst. & G.Forst. is a complex genus of orchids consisting The eight currently known taxa in of about 100 described species, several described natural hybrids and the Thelymitra variegata (Lindl.) F.Muell. complex are reviewed and at least 13 undescribed taxa. It is concentrated in higher rainfall areas of descriptions are presented for each. temperate Australia, but a few species occur in tropical north-eastern Thelymitra pulcherrima Jeanes, Australia, about 20 species occur in New Zealand (15 endemic) and a T. speciosa Jeanes and T. uliginosa few species occur in Indonesia, New Caledonia, New Guinea and the Jeanes from southwestern Western Philippines. Australia are described as new and illustrated. Thelymitra spiralis (Lindl.) This is one of a series of papers by the author reviewing the various F.Muell. var. pulchella Nicholls is morphologically distinct groups or complexes within Thelymitra. raised to species rank and given the During the course of my studies of the Thelymitra variegata (Lindl.) new name T. maculata Jeanes as the F.Muell. complex it became evident that several undescribed species epithet ‘pulchella’ is unavailable. The were present within the group. I take this opportunity to descibe these key diagnostic features relating to new species and review the entire complex. the size and colour of the perianth, the size, colour and shape of the There are a number of morphological features that, in combination, lateral lobes of the column and distinguish members of the T. variegata complex from all other leaf characteristics are elucidated. Thelymitra species. The leaf is usually variously auriculate at the base Information on distribution, habitat, and the blade is usually spirally twisted or at least somewhat curved. pollination biology, flowering time The leaf is also pubescent at the base with the hairs mainly on the veins and conservation status is given for all eight taxa. The main distinguishing and margins. The flowers usually have strong lustrous colours, often in features of Thelymitra apiculata (A.S. combinations of pink, red, yellow, mauve or purple. The column has a George) M.A.Clem. & D.L.Jones, rudimentary post-anther lobe with an arc of small digitate to globose T. matthewsii Cheesem., T. spiralis, glands arranged between the bases of the lateral lobes. The lateral T. variegata and the four new species lobes are well-developed and prominent, stipitate, suborbicular to are tabulated. A key is provided to narrow-elliptic and smooth to rugulose. The anther has an elongate distinguish all eight members of the T. variegata complex. terminal beak that is essentially an extension of the connective (see Fig. 1). Although six of the eight species in the complex are apparently Muelleria 27(2): 149-170 (2009) insect-pollinated, it is interesting to note that no floral odours have ever been attributed to the group. The likely mechanism for pollination is floral mimicry of other wildflowers (A. Brown pers. comm.) Muelleria 149 Muelleria rec 27-2 text.indd 149 1/07/2009 9:26:09 AM Jeanes Taxonomic history Hoffman and Brown (1998) followed their earlier work but also recognised two informal taxa, both as T. aff. The first two species in the group to be recognised, variegata, one from north of Perth, the other from the Thelymitra variegata and T. spiralis (Lindl.) F.Muell., south coast of Western Australia. Brown et al. (2008) were described by Lindley (1839–40) as Macdonaldia recognised and illustrated the seven Western Australian variegata Lindl. and M. spiralis Lindl. respectively species described in this paper, either by their currently (see Discussion for notes on Macdonaldia). Mueller accepted names or the manuscript names ascribed by (1865: pp 97–98) described T. porphyrosticta F.Muell. the current author. and commented that his new species was similar to T. variegata and T. spiralis thereby effectively creating these two new combinations. Bentham (1873) Discussion recognised only T. variegata while reducing T. spiralis Historically there has been significant confusion about and T. porphryosticta to synonymy. Mueller (1882) the correct application of names and the interpretation followed Bentham’s classification. Cheeseman (1911) of species within the Thelymitra variegata complex. described T. matthewsii Cheesem. from plants found on At least some of this confusion has persisted to the the North Island of New Zealand and later Rogers (1930), present day and has revealed itself in the many floras apparently unaware of Cheeseman’s species, described and orchid books published over the years. T. daltonii R.S.Rogers (as T. D’Altonii) from Halls Gap in Lindley (1839–40) described the first two species the Grampians, Victoria. Nicholls (1949) created four in the group as Macdonaldia variegata and M. spiralis varieties of T. spiralis—T. spiralis var. scoulerae Nicholls, respectively and distinguished these, and several T. spiralis var. pallida Nicholls, T. spiralis var. punctata other apparently unrelated species, from Thelymitra Nicholls and T. spiralis var. pulchella Nicholls—all of in having “the anther incumbent, and not parallel with which, as well as the type variety, are well illustrated the stigma”. The generic name Macdonaldia Gunn in colour in Nicholls (1951). George (1971) recognised ex Lindl. was coined by the notable plant collector all of Nicholls’ varieties except var. pulchella, which Ronald Gunn in honour of Mrs Smith née Macdonald he relegated to synonymy under the type variety. He an orchid collector from Tasmania. Hooker (1858) also relegated T. porphryosticta to synonymy under reduced Macdonaldia to a section within Thelymitra T. variegata and recognised T. matthewsii as occurring differing from his other sections in having the “Column in Western Australia. George (1984) described bifid at the apex, its sides not produced into toothed T. variegata var. apiculata A.S.George from plants or feathery arms. Anther projecting, generally more collected between Eneabba and Mogumber north or less granular or villous”. Mueller (1865, p. 98) did of Perth. Jones (1988) followed George (1971), but not recognise Macdonaldia and created the new in a brief entry in the supplement at the back of the combinations T. variegata and T. spiralis. In the same book T. variegata var. apiculata was raised informally article, Mueller (1865) described T. porphyrosticta to species rank as T. apiculata (A.S.George) M.A.Clem. from specimens collected by Maxwell near Salt & D.L.Jones. Following Clements’ study of the various River and Kalgan in Western Australia. Following type specimens, Clements and Jones in Clements my examination of the two type specimens at MEL, I (1989) formally raised T. variegata var. apiculata to have concluded that one (Kalgan River) is referable to species rank as T. apiculata. Otherwise Clements (1989) T. variegata (lectotypified below) the other (Salt River) recognised only T. matthewsii, T. spiralis var. spiralis, to T. spiralis (rejected syntype). A specimen at Kew (not T. spiralis var. pulchella and T. variegata as distinct seen by me) collected by Maxwell at Kalgan River is an taxa. Hoffman and Brown (1992) recognised only isolectotype (George 1971). Bentham (1873) recognised T. apiculata, T. spiralis and T. variegata as occurring in only T. variegata while relegating T. spiralis (and Western Australia, although they do allude to T. spiralis T. porphyrosticta) to synonymy therein. Bentham (1873) var. pulchella and the taxon from Western Australia that recognised Macdonaldia as a section within Thelymitra was equated by George (1971) with T. matthewsii as and defined it as “Column-wing broadly produced possibly being distinct entities worthy of recognition. behind the anther, but much shorter than it, and not 150 Vol 27(2) 2009 Muelleria rec 27-2 text.indd 150 1/07/2009 9:26:09 AM Muelleria rec27-2text.indd 151 Table 1. Taxonomic history of the T. variegata complex showing the names in Macdonaldia and Thelymitra used by various authors for the eight taxa recognised in the current treatment Muelleria Author Name used Lindley (1839–1840) M. variegata M. spiralis n/a n/a n/a n/a n/a n/a Lindley (1840) M. variegata M. spiralis n/a n/a n/a n/a n/a n/a Mueller (1865) T. variegata T. spiralis n/a n/a n/a n/a n/a n/a T. porphryosticta T. porphryosticta Bentham (1873) T. variegata T. variegata n/a n/a n/a n/a n/a n/a Mueller (1882) T. variegata T. variegata n/a n/a n/a n/a n/a n/a Cheeseman (1911) T. variegata none T. matthewsii n/a n/a n/a n/a n/a Rogers (1930) T. variegata T. spiralis T. D’Altonii n/a n/a n/a n/a n/a Nicholls (1949), Nicholls T. variegata *T. spiralis var. spiralis T. matthewsii T. spiralis var. n/a n/a n/a n/a (1951) & Nicholls (1969) T. spiralis var. scoulerae pulchella T. spiralis var. pallida T. spiralis var. punctata George (1971) T. variegata T. spiralis var. spiralis T. matthewsii T. spiralis var. n/a T. matthewsii n/a n/a T. spiralis var. scoulerae spiralis T. spiralis var. pallida T. spiralis var. punctata T. spiralis var. pulchella Hoffman & Brown T. variegata T. spiralis none none T. sp T. matthewsii n/a n/a (1984) George (1984) T. variegata var. none none none T. variegata none n/a n/a variegata var. apiculata Jones (1988) T. variegata *T. spiralis var. spiralis T. matthewsii none T. variegata T. matthewsii n/a n/a T. spiralis var. scoulerae var. apiculata T. spiralis var. pallida T. apiculata variegata Thelymitra T.