Flora of New Zealand Series

Veronica catarractae Forst. f. Prodr. 1786, 3.

V. diffusa Hook. f. Ic. Pl. 1844, t. 645 non Raf. New Fl. Amer. 4, 1836, 38.

V. lanceolata Benth. in DC. Prodr. 10, 1846, 462.

V. irrigans Kirk in T.N.Z.I. 2, 1870, 94.

P. diffusa (Hook. f.) W. R. B. Oliver loc. cit. 230.

Type: K, Forster.

Decumbent to ascending openly branched subshrub; stems and branches woody in older parts, sts rooting where prostrate, bifariously or rarely uniformly pubescent with short crisped hairs. Lvs distant to close-set, membr. to subcoriac.; lamina (5)-10-40-(90) × (3)-5-20-(25) mm., ovate to elliptic to lanceolate to narrowly linear-lanceolate, coarsely to shallowly serrate, acute, subsessile or cuneately narrowed into stout petiole 2-5 mm. long, sts truncate or subauricled, glab. except for pubescent midrib and petiole above, dark green above, pale or more distinctly white to yellowish below. Racemes us. long and ∞-fld; peduncles 3-10 cm. long, glab. or sparsely pubescent; bracts 3-5-(10) mm. long, linear-lanceolate to narrow-ovate, lower ones sts subfoliaceous, glab.; pedicels 5-15-(20) mm. long, white-pubescent or glandular-hairy or sts ± glab. Calyx-lobes 2-3 mm. long, ovate, acute or acuminate by incurved margins, sparsely ciliolate. Corolla white veined with pink or purple, c. 1 cm. diam.; tube c. 1 mm. long, much < calyx; lobes 4, unequal, spreading, obtuse. Capsule c. 3-4 × 3 mm., > calyx, broadly obcordate, ± turgid, glab.

DIST.: N., S., St. Lowland to montane damp streamsides, cliffs and rocky places, subalpine in Tararua Range, mainly west of divide in S.

Fl. 11-4-(7). FT. 12-5-(8).

The above generalized description covers a polymorphic range of forms that cannot be divided into a series of clear-cut vars. Floral characters are rather constant and of little taxonomic value while habit and lf-size are plastic and greatly influenced by habitat conditions. Lf-shape has been the main basis for subdivision but it is not always adequate, and in some cases it is impossible to recognize vars on this alone; correlation with other characters (particularly pubescence) is largely lacking. Nevertheless some combinations of minor characters are locally stable and with a good field knowledge a number of regional and altitudinal races can be recognized. Several forms have been named but the application of the names is confused.

Forster's original diagnosis is merely: "racemis terminalibus flexuosis, caulc suffruticoso, foliis lanceolatis serratis. Nova Zeelandia". The type at K (which matches a specimen at BM) has lanceolate lvs c. 4 × 1 m.; it very probably came from Dusky Sound as the sp. has not been found along the shores of the Marlborough Sounds, the only other locality where the Forsters collected.

V. lanceolata Benth. in DC. Prodr. 10, 1846, 462 was based on material collected by Dieffenbach. The lvs were described as lanceolate while a var. angustifolia with linear-lanceolate lvs was also distinguished from the same collection. Possible types in K are two Dieffenbach specimens labelled "Mts of the Interior"; one, included with the Dusky Bay plants, has narrow-lanceolate lvs c. 7 × 1 cm., and the other, in the lanceolata folder, has exceedingly narrow lvs c. 2.5 cm. long. Similar extremely narrow-lvd plants from the Thames goldfields were later described by Kirk as V. irrigans; supporting material is in W.

Hooker (Fl. N.Z. 1, 1854, 195) treated V. lanceolata as a var. of V. catarractae, giving the lvs as narrowly linear-lanceolate, and also described, without locality, var. minor with lanceolate lvs 1 inch long.

Lvs of lanceolate order, but not uncommonly varying in shape and size within one population, are found on plants from lowland to montane valleys of North Id, Nelson, the west coast of the South Id and Stewart Id. Those of plants from Fiordland and Stewart Id range from ovate-lanceolate to linear and from 20 to 90 mm. long and 4 to 25 mm. wide; all differ from North Id specimens in soft white to yellow undersurface (brown when dry) and are often larger, more coarsely serrate and almost acuminate. Though Forster's type probably came from this district its lvs are comparatively small and the white undersurface apparently is much less obvious than in the luxuriant specimens collected at Dusky Bay by Lyall, also at K, which were mentioned by Hooker loc. cit. 195. In parts of the North Id, particularly about Auckland, Thames and New Plymouth, occur plants with narrow-lanceolate to linear lvs corresponding to V. lanceolata (including var. angustifolia) and to V. irrigans. Lowland to lower montane plants of the Tararua and Ruahine Ranges, like some from the northern part of the South Id, have rather small lanceolate to ovate-lanceolate lvs and may correspond to Hooker's var. minor, though Cheeseman notes that N. E. Brown considered that name to have been based on Forster's type.

V. diffusa Hook. f. Ic. Pl. 1844, t. 645 (V. catarractae var. diffusa Hook. f. Handbk N.Z. Fl. 1864, 216) was based on a Bidwill collection from Tongariro. The figure shows a robust decumbent plant with long glandular racemes and ovate to elliptic lvs which can be well-matched by luxuriant plants from valleys in the Volcanic Plateau, but the name is commonly applied to all plants with lvs of ovate order including several North Id montane to subalpine races with smaller, more coriac. lvs. The distinction between ovate and lanceolate lvs is often difficult to maintain, both between and within populations, and there is a lack of other correlated differences.

Specimens from certain localities in Marlborough (e.g. Ure R., Swale R., Palmer R.) have sts also been placed in diffusa but could almost equally be referred to P. lyallii; infls are glab. or nearly so, stems glab. or faintly bifariously pubescent; lvs ovate to ovate-oblong to obovate, 10-25 × 6-11 mm., us. rather shallowly serrate, apex obtuse to subacute.

Also of uncertain position are slender plants with small ovate lvs ± 5-10 × 4-9 mm. which occur in several North Id localities. Some, e.g. from Kaimanawa and N.W. Ruahine Ranges, appear to be merely habitat-induced forms; others, e.g. from the Wairarapa, may belong to distinct small-lvd races; they confuse the limits between P. catarractae, P. hookeriana var. olsenii and P. lyallii.