Sophora (Fabaceae) in New Zealand: Taxonomy, Distribution, and Biogeography
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New Zealand Journal of Botany ISSN: 0028-825X (Print) 1175-8643 (Online) Journal homepage: http://www.tandfonline.com/loi/tnzb20 Sophora (Fabaceae) in New Zealand: Taxonomy, distribution, and biogeography P. B. Heenan , P. J. de Lange & A. D. Wilton To cite this article: P. B. Heenan , P. J. de Lange & A. D. Wilton (2001) Sophora (Fabaceae) in New Zealand: Taxonomy, distribution, and biogeography, New Zealand Journal of Botany, 39:1, 17-53, DOI: 10.1080/0028825X.2001.9512715 To link to this article: http://dx.doi.org/10.1080/0028825X.2001.9512715 Published online: 17 Mar 2010. Submit your article to this journal Article views: 792 View related articles Citing articles: 29 View citing articles Full Terms & Conditions of access and use can be found at http://www.tandfonline.com/action/journalInformation?journalCode=tnzb20 Download by: [203.173.191.20] Date: 05 August 2017, At: 06:35 New Zealand Journal of Botany, 2001, Vol. 39: 17-53 17 0028-825X/01/3901-0017 $7.00 © The Royal Society of New Zealand 2001 Sophora (Fabaceae) in New Zealand: taxonomy, distribution, and biogeography P. B. HEENAN and Manawatu, and S. molloyi is restricted to ex- Landcare Research tremely dry and exposed bluffs and rock outcrops of P.O. Box 69 southern North Island headlands, Kapiti Island, and Lincoln, New Zealand several islands in Cook Strait. Cluster analyses of 11 leaf and 4 growth habit P. J. de LANGE characters provide additional support for the revised Science & Research Unit classification, and variation in 7 leaf characters is Department of Conservation evaluated with box plots. A key is provided to Private Bag 68908 Sophora in New Zealand, hybridism is discussed, an Newton assessment of each species' conservation status is Auckland, New Zealand made, and biogeography is reconsidered in view of the new taxonomic treatment. A. D. WILTON Landcare Research Keywords Fabaceae; Sophora; S. cassioides; S. P.O. Box 69 chathamica; S.fulvida; S. godleyi; S. longicarinata; Lincoln, New Zealand S. microphyllu; S. microphylla var. fulvida; S. molloyi; kowhai; taxonomy; biogeography; conser- vation; New Zealand flora Abstract A taxonomic treatment is provided for the Sophora microphylla complex in New Zealand. Sophora microphyllu sens. str. is endemic to New Zealand, and includes those plants with a distinct INTRODUCTION divaricating and/or strongly flexuose juvenile Phase, The taxonomy of Sophora (kowhai) in New Zealand orange-brown to Yellow-brown Juvenile stems, and has had a complex and problematic history that is distant leaflets. S. chathamica is reinstated at spe- embodied in the following quote from Bentham (in cies rank, S.fulvida is a new combination provided Hooker 1853, p. 52): "I cannot find any character to for the taxon previously known as S. microphylla distinguish the New Zealand Edwardsiae from each Downloaded by [203.173.191.20] at 06:35 05 August 2017 Var. fulvida, and S. godleyi and S. molloyi are de- other, even as varieties: the leaves ... show every scribed as new species. S. chathamica, S. fulvida, S. gradation from the one to the other; so that I have in godleyi and S. molloyi lack a divaricating and/or vain attempted to sort your specimens into varieties, strongly flexuose juvenile phase and are each dis- without making one for almost every specimen." tinguished by a number of leaf characters. S. fulvida Nearly 90 years later, the genus was still taxo- and S. godleyi have distinctive leaf hairs. S. nomically difficult, and Bentham's musings were chathamica is a predominantly coastal species in endorsed by Simpson & Thomson (1942, p. 24), Northland, Auckland, Waikato, Wellington, and the who, when describing S. longicarinata, commented Chatham Islands, S.fulvida occurs in Northland and "We had prepared a description for a beautiful plant North Auckland on volcanic rock outcrops S. from Haulashore Island, Nelson,... and one for an godleyi Occurs on calcareous mudstone and sand- equally fine plant of Piha Auckland, ... but... we stone in eastem Taranaki King country, Wanganui hesitate to make distinctions. The genus is much in need of study to separate the many forms." The early flora treatments for Sophora in New Zealand clearly reflect these problems, with Hooker B99050 (1853, 1867), Kirk (1899), and Cheeseman (1906) Received 1 October 1999: accepted 31 August 2000 all treating S. microphylla Aiton as a variety of S. 18 New Zealand Journal of Botany, 2001, Vol. 39 tetraptera J.S.MilI., or its synonym S. grandiflora named the Chatham (Rekohu) Islands plants as S. Salisb. Cheeseman (1929, in the second edition of chathamica. Cockayne also considered S. chatham the Manual of the New Zealand Flora, accepted S. ica to be common in the Auckland area (Cockayne microphylla, S. tetruptera, and S. prostrata 1927, p. 97; Cockayne & Phillips Turner 1928, p. Buchanan at species rank. 51), and he noted that the kowhai from Chatham Allan (1961) also accepted S. microphyllu at Islands, the Auckland area, and Chile were similar species rank, but recognised an additional two in lacking a juvenile growth form (Cockayne 1899, varieties (Table 1). One of these, S. microphyllu var. p. 373; Cockayne 1912, fig. 1,2). Godley (e.g., 1975, longicarinata (G.Simpson et J.S.Thomson) Allan, 1979a, 1979b; Godley & Smith 1977; Sykes & was a new combination for the species first described Godley 1968), in a study of habit-heteroblasty in by Simpson & Thomson (1942) and recently Sophora from throughout New Zealand, also reinstated by Heenan (1998a). The other, S. reported that races from Northland, Auckland, microphyllu var. fulvida Allan, was a new variety Chatham Islands, Chile, and Gough Island in the considered to be restricted to parts of the western South Atlantic lacked a juvenile form typical of S. Waitakere coast, North Auckland (Allan 1961). The rnicrophylla. In addition, Godley (1975, 1979a, distinctiveness of S. rnicrophylla var. fulvida was 1979b) reported thatS. rnicrophylla var. fulvidu, and first recognised by H. H. Allan who "suggested ... other plants from the Whanganui River and that the tree ... which occurs in a restricted area Ohingaiti (Rangitikei River, North Island), also around Anawhata, near Auckland, is either a variety lacked the distinctive juvenile phase. of & microphylla ... or a distinct species" (Briggs & The Whanganui River plants of Sophora were Mangan 1948, p. 1889). Briggs & Mangan were treated as a distinct geographic race in a study of the prompted by Allan to investigate the seed alkaloid phenolic compounds of Sophora (Markham & compounds of this then unnamed Sophora, and they Godley 1972), but their taxonomic status was not concluded that the results "support the classification investigated. The first collection of the Whanganui of this plant as a new species". Earlier, Petrie had River/Rangitikei form was by W. Colenso in Decem- collected S. microphyllu var. fulvidu from the ber 1848 from the Oroua River, on the western flanks Waitakere Ranges (e.g., WELT 19452, "the only of the Ruahine Range (Colenso Herbarium 2319, form found thereabouts"), and he cultivated it at his WELT 23904; unpublished letter to W. J. Hooker, daughter's farm at Pukeatua, west Taupo (e.g., June 1850). In obvious reference to the distinctly WELT 19456A). A description of the Waitakere plants was also prepared by Simpson and Thomson hairy leaves, Colenso, in his letter to Hooker, called but not published (Simpson & Thomson 1942). it "E. velutina n.sp. W.C.", and the WELT herbarium sheet is labelled as "Edwardsia velutina". A contribution to Sophora taxonomy was also Most recently, another form of Sophora that is made by Cockayne (1902, pp. 279, 319), when he shrubby, sometimes prostrate, and particularly leafy Downloaded by [203.173.191.20] at 06:35 05 August 2017 Table 1 Comparison of taxonomic treatments of Sophora in New Zealand. Current revision Allan (1961) Yakovlev(1967) Tsoong&Ma(1981) S. chathamica synonym of S. rnicrophylla S. microphylla subsp. S. chathamica microphylla var. chathamica S. jiilvida S. rnicrophylla var. fulvida S. microphylla subsp. microphylla var. fulvida S. godleyi _ S. longicarinata S. microphylla var. S. microphylla subsp. longicarinata microphylla var. longicarinata S. microphylla S. rnicrophylla var. S. microphylla subsp. S. microphylla rnicrophylla microphylla var. microphylla S. molloyi - S. prostrata S. prostrata S. microphylla subsp. S. prostrata rnicrophylla var. prostrata S. tetraptera S. tetraptera S. tetraptera S. tetraptera Heenan et al.—Sophora in New Zealand 19 has been reported from several islands in Cook Strait When reinstating S. longicarinata and in selecting (Atkinson & Bell 1973; Walls 1979, 1981, 1982, a lectotype for S. microphylla (Heenan 1998a), it was 1986; Ogle 1983). This shrubby form is often necessary to critically examine a large amount of cultivated as an ornamental species in New Zealand, plant material of S. microphylla sens. lat. During that and the growth habit of a mature cultivated plant has study, it became apparent that S. microphylla sens, been described (Heenan 1992). lat. exhibited distinct patterns of variation in leaf and Several authors from outside of New Zealand growth-habit characters. The results of subsequent have contributed to the taxonomy of the New Zea- field, herbarium, statistical, and cultivation studies land species ofSophora. A revision of Sophora sect. of the S. microphylla complex are reported in this Edwardsia, to which the New Zealand species be- paper. long, was provided by Yakovlev (1967) (Table 1). He accepted S. tetraptera at species rank and, in a rather unconventional treatment, recognised a number of varieties of S. microphylla. The most MATERIALS AND METHODS recent treatment of the New Zealand species was Field studies of Sophora have been made through- provided by Tsoong & Ma (198l), who accepted S. out New Zealand by PBH and PJdL during the prostrata, S. microphylla, S. tetraptera, and S. 1990s. In particular, during August 1997 field work chathamica (Table 1). was undertaken on S. chathamica, S.fulvida and S.