Flora of New Zealand Series

Polygonum complexum A. Cunn. in Ann. nat. Hist. 1, 1838, 455.

Type locality: "sandy shores of the Bay of Islands, where it forms dense bushes". Type: K, No. 357 Allan Cunningham, 1826.

Rather stout dioec. liane up to ± 6 m. tall, much-branched, branches ± interlacing (forming tangled masses in absence of support). Main stems us. not > 5 cm. diam.; branchlets very slender, terete, ± striate, pubescent in early growth, bark dark to rather light reddish brown. Lvs on petioles up to 1 cm. long; lamina dark green above, paler and often glaucous below, 5-20 × 2-15 mm., glab., coriac. to submembr., of diverse form (several forms may be on same plant); margins us. not undulate; broad-oblong to obovate to suborbicular, rounded to retuse at apex, truncate to rounded or occ. subcordate at base. Ochreae deciduous, seldom > 4 mm. long. Infl. ± 1-2-(4) cm. long, of simple or branched spikes, glab. or pubescent. Spikes axillary and terminal, sts reduced to small clusters. Fls small, tepals cut ⅔ to base; ♂ with 8 stamens, ♀ with broad fimbriate stigmas; tepals enlarged in fr., us. succulent, white. Fr. black, glossy, trigonous, ± 2 × 1·75 mm.

DIST.: N., S., St. Coastal, lowland and lower montane forests, especially marginal, throughout; also open and rocky places.

FL.- FT. 11-2-(6).

A complicated aggregate of forms is at present included under this name-the complexity not resolvable by methods so far adopted. Cunningham's description is: "glabrum dumosum, caule fruticoso flexuoso, foliis (semiuncialibus) subrotundis petiolatis subcordatis margine integerrimis, racemis axillaribus terminalibusve, floribus polygamis? ramulis volubilibus implexis scabris". The type at K is a small tangled mass with very few lvs and poor infls left; lvs ± 7·5 mm.

The following forms have received names:

1. var. grandifolia Carse in T.N.Z.I. 48, 1916, 239. "Frutex ramosissimus scandens, habitu M. australis Meissn. Caudex 12-25 mm. diam. Rami teretes, ultimati pubescentes. Folia 25-75 mm. longa, oblongo-ovata, acuminata, ad basim cordata vel truncata, coriacea, glaucosa infra. Flores in spicas 50-75 mm, longas. Perianthus in fructu non succulens . . . Confined to damp alluvial situations." Type: 641/1 Carse Herb. CM. "Creek bank, Duncan's Rd. Otukau, Mangonui. April 1916. H. Carse." Dist. Mangonui County. A plant not distinguish- able from the type was found near Palmerston North.

2. M. microphylla Col. in T.N.Z.I. 20, 1888, 204. M. complexa var. microphylla (Col.) Ckn. in T.N.Z.I. 48, 1916, 208. "Plant shrubby, depressed, 3-4 feet high, forming dense . . . bushes; main stems 1/4-3/4 inch diameter . . . bark light-red, glossy. Leaves very few . . . mostly suborbicular, oblate and broadly elliptic, 1/2-1 line (rarely 2 lines) long . . . ochrea rather large, bladdery . . . Flowers axillary, 3-5-7 together . . . perianth . . . segments cut nearly to base . . . not succulent . . . Nuts small, 1/10 in. long, blackish brown . . . finely tuberculate or rugulose, not glossy. Hab. Dry stony places; on ridges and mounds on hills, various places in Hawke's Bay; 1850-1886: W.C." Type not seen, but similar forms are often met with.

3. M. muricatula Col. in T.N.Z.I. 22, 1890, 482. M. ephedrioides var. muricatula (Col.) Cheesem. Man. N.Z. Fl. 1906, 594. "A small low prostrate wiry undershrub. Branches inflexed, long, very slender, striate . . . branchlets few, almost filiform . . . Leaves . . . linear, 4-5 lines long . . . stipules large . . . truncate . . . Flowers hermaphrodite, axillary, 2 together. Perianth white, 11/2 lines diam . . . Nut black . . . 11/4 lines long . . . angles obtuse; the perianth-lobes persistent, membranous. Hab. Summit of Mount Ruapehu, and within the old crater, on dry stony spots . . . 1889: Mr H. Hill." The type, in W, has several slender lfy branchlets; lvs linear to linear-spathulate, up to 8 mm. long on short petioles; racemes up to 2 cm. long.

4. M. paucifolia Col. in T.N.Z.I. 21, 1889, 99. "A low prostrate rambling shrub, extending 5 ft.-6 ft. Branches stout, bark . . . dark red-brown. Leaves few . . . light-green, broadly elliptic and sub-rotund, 3-6 lines long . . . submembranous . . . petioles . . . finely and closely tuberculate . . . Flowers in terminal racemes at tips of short lateral branchlets; racemes . . . about 1/2 in. long, finely pilose, each bearing 5-7 (rarely 9) flowers . . . bracts (ochreae) rather large, open, glabrous, pale reddish-brown, obliquely truncate, accuminate with one long stout sub-aristate nerve . . . Perianth (and pedicel) white, lobes cut half-way to base . . . Ovary (immature) pink, slightly tuberculate. Hab. On mounds of indurated pumice, &c., at Whangawehi, north side of Table Cape; December, 1887: Mr. A. Hamilton." The type, in W. has one divaricately branched, very rigid piece, diam. ± 4 mm., with a few lvs and a few imperfect spikes up to 1 cm. long. There is a packet of lvs and one of racemes. Lvs ± 1 × 1 cm., almost quadrate to broad-oblong, subcordate to truncate at base, some lvs subpanduriform.

5. M. trilobata Col. in T.N.Z.I. 21, 1889, 100. M. complexa var. trilobata (Col.) Cheesem. Man. N.Z. Fl. 1925, 402. "Plant decumbent . . . rising, twining and climbing over low shrubs and herbage. Branches long, striate, densely pubescent . . . Fem.: leaves . . . membranaceous, glabrous, green . . . broadly ovate (in outline), 3/4 in.-11/4 in. long, 3/4 in.-1 in. wide, wavy, sub-panduriform, deeply trilobed, largely cordate . . . tip suddenly acute and sub-apiculate . . . Petioles 1/2 in.- 3/4 in. . . . pubescent . . . Ochreae large, truncate, pubescent on nerves. Flowers irregularly disposed, usually in axillary racemes 2 together; racemes rather slender, nodding, 2 in.-21/2 in. long (sometimes panicled . . . ) . . . flowers subfascicled . . . pedicels . . . capillary . . . Perianths pale-green . . . 2 lines diam . . . Nut black, shining . . . 2 lines long, triquetrous. Male (also, sometimes, hermaphrodite): leaves much smaller. Racemes axillary and terminal . . . 1 in.-2 in. long . . . 4-5 flowers in 1 sheath; perianth membranous, greenish-white . . . stamens . . . flexuous . . . Nut sometimes as in female. Hab. In woods south of Dannevirke . . . 1888: W.C." The type specimen, in W, has lvs ± 3 × 3 cm., deeply lobed, and as described by Colenso. The Colenso specimen at K is similar. Plants ± answering the description are not uncommon.

6. M. truncata Col. in T.N.Z.I. 21, 1889, 101. "A slender rambling climbing twining shrub, rising to 8 ft.-9 ft. among shrubs and trees. Branches very long and slender, flexuous, closely twining, thickly pubescent . . . Fem.: leaves membranous, numerous . . . broadly oblong, 1/2 in.- 3/4 in. long, sides straight . . . base truncate, dull pale-green, glabrous, wavy . . . Petiole . . . almost capillary . . . racemes 1/2 in.-1 in. long, and 5-12 flowered . . . sheaths . . . with 1 long stout excurrent nerve . . . perianth whitish or very pale-green . . . Nut . . . about 1 line long . . . angles obtuse . . . dull . . . Male: leaves smaller and slightly contracted at the middle . . . racemes 1/2 in.-1 in. long, 8-15 on a raceme . . . Perianth-lobes obovate, cut nearly to base . . . Hab. [same as for M. trilobata]." The type. in W, consists of several slender lfy branchlets; oblong ± constricted lvs 9-11 × 7-8 mm., with smaller ones; racemes ± 1 cm. long.

7. M. varians Meissn. in Schlecht. Bot. Ztg. 10, 1852, 347. "glaberrima . . . fol. Petiolatis ovatis acute acuminatis basi truncato-subcordatis, aliis integerrimis, aliis (praecipue in ramis florentibus) utrinque prope medium sinu obtuso profundo pandurae formibus." From garden plants sent by A. Braun (Berlin Botanic Garden). Agrees well with M. trilobata Col.

POLYMORPHY AND HYBRIDISM

It is probable that hybridism plays a part in the polymorphy found in the field, but little more than casual observations have been made. Allan (Genetica 8, 1926, 531) under the name × M. austracompla described and illustrated plants of a rather uniform form that he considered hybrids between M. australis and M. complexa, both plentiful in the immediate neighbourhood. Cockayne and Allan (T.N.Z.I. 57, 1926, 70-71) recorded a plant from an old flood-plain of the Waitaki River near Kurow as M. complexa × ephedroides. They also considered M. muricatula Col. to be a hybrid between M. axillaris and M. ephedroides, basing their view on plants studied from the Awatere River and the Ashburton River. Aberrant forms certainly occur in these and other areas, but are us. much stouter than the type of M. muricatula.

Cockayne and Allan (Ann. Bot., Lond. 48, 1934, 20) list the following groups: M. australis × complexa; M. axillaris × complexa; M. axillaris × ephedroides; M. complexa × ephedroides. All are based on rather scanty field evidence, and the complication caused by habitat-induced modifications is mentioned. The status of M. debilis Petrie in T.N.Z.I. 56, 1926, 10 needs further study. Petrie's description is: " Species M. complexae (Meissner) affinis; differt caulibus gracilioribus viridibus vel cinerascenti-viridibus, ubique glaberrimis ramis ramulisque distantibus subdivaricatis pergracilibus, foliis multo angustioribus plerumque lineari-lanceolatis acuminatisque, floribus in spicis simplicibus dispositis, periantho in fructu maturo herbaceo haud incrassato." He adds: "forming low widespreading more or less entangled sheets in moist stations, or broad erect and finally pendulous dense rush-like tufts on gravelly terraces . . . leaves . . . usually linear-lanceolate and acuminate, entire, 10-20 mm. long . . . (rarely shorter and contracted about the middle with rather wide basal lobes) . . . Spikes . . . 3-4 cm. long in male plants . . . males . . . perianth deeply cut into semihyaline narrow-oblong obtuse divisions; females with somewhat broader perianth-lobes . . . nut black and shining, deeply triquetrous . . . Hab. On low gravelly terraces and the immediate banks and rocky faces of the Awatere and Grey Rivers, close to the Homestead of Upcot Station, Middle Awatere, Marlborough. Flowers in February." The type, in W, "Upcot, Banks of Grey and Awatere Rivers, D.P. early Febry 1922" consists of 3 pieces, all with ∞ ♂ spikes, and conforms to the description. Other specimens in the folder approach M. complexa. A ♂ specimen collected by G. Simpson from the "Waimakariri River near road to Mount White, 2/9/1949" (BD 87205) closely resembles the type.