The New Zealand Plant Conservation Network

Species

Convolvulus verecundus f. glaberrimus

Etymology

Convolvulus: From Latin convolvere, which means to twine around
glaberrimus: From 'glaber' (hairless) and 'rimus' (to the greatest degree) i.e. 'extremely hairless'

Current Conservation Status

2019 - Threatened - Nationally Critical

Conservation status of New Zealand indigenous vascular plants, 2012
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2012 using the New Zealand Threat Classification System (NZTCS). This report includes a statistical summary and brief notes on changes since 2009 and replaces all previous NZTCS lists for vascular plants. Authors: Peter J. de Lange, Jeremy R. Rolfe, Paul D. Champion, Shannel P. Courtney, Peter B. Heenan, John W. Barkla, Ewen K. Cameron, David A. Norton and Rodney A. Hitchmough. File size: 792KB

Authority

Convolvulus verecundus f. glaberrimus Heenan et Molloy

Family

Convolvulaceae

Brief Description

Scrambling plant allied to Convolvulus verecundus f. verecundus from which it differs by the brown-green, glabrous to glabrate leaves, with prominent and strongly translucent veins, and undulating to occasionally sinuate leaf margins.

Flora Category

Vascular - Native

Structural Class

Dicotyledonous Herbs other than Composites

Synonyms

None - first described in 2019

Distribution

Endemic. South Island, North Otago, Awahokomo

Habitat

Limestone endemic. Known from one location where it grows on ledges, cracks and crevices infilled with limestone fragments, and on shallow skeletal rendzina and colluvium.

Features

Low-growing perennial herb, with creeping rhizomatous stems, short ascending to spreading branches, and lianoid stems up to 200 mm; lianoid stems with a sparse to moderate covering of retrorse hairs. Leaves in rosettes and alternate on stems, 6.5–12.0 × 4.0–8.0 mm, deltoid, deltoid-ovate to ± broad-oblong, brown-green, glabrous to glabrate; veins prominent and strongly translucent; margin undulate, occasionally sinuate; base truncate, obtuse, occasionally oblique or slightly cordate; apex usually retuse or obtuse; petiole channelled, glabrous to glabrate. Pedicel 5–30(–55) mm long, 0.4–1.2 mm diam., moderately hairy. Sepals 3.9–4.1 × 3.5–3.8 mm, obovate to ovate, green; abaxial surface sparsely to moderately hairy, adaxial surface glabrous; margin fimbriate and translucent; apex subacute to obtuse. Corolla 12–19 mm long in bud, 20–25 mm wide when open, white, rarely pink, five lobes fused their full length, lobe apex fringed with hairs; tube 5–8 mm long, pale green; abaxial surface with midline of petal with pink bands with sparse appressed hairs on upper half. Nectary annular, 0.3–0.4 mm tall, yellow. Style 2-cleft, white; fused portion 6.0–9.0 mm long, c. 0.2 mm wide; stigmata 2.5–4.0 × c. 0.5 mm. Ovary c. 1.0 × 1.0–1.2 mm, cream. Filaments 4.0–4.6 mm long, c. 0.5 mm wide at base, tapering to c. 0.2 mm at apex, white; margin with scattered short hairs on lower half; fused to base of corolla tube. Anthers 1.7–2.0 mm long, white. Capsule 5.8–6.2 mm long, 4.5–7.5 mm wide, chartaceous, globose, with 2–4 seeds, lower half enclosed in persistent calyx, style base remnant persistent. Seeds segment-shaped and broader toward apex with a rounded dorsal and two flattened lateral faces meeting at an acute ventral edge, or rounded and broadly obovate without distinct angles, almost triangular to terete in section; 2.8–3.9 × 2.4–3.0 mm; apex and base rounded; hilum concave. Testa black-brown overlaid and ornamented with grey nut-brown, dull, glabrous, moderately covered in low ridges and tubercules, sometimes forming ridges on margins

Similar Taxa

Most similar to Convolvulus verecundus f. verecundus from which it differs by the brown-green, glabrous to glabrate leaves, with prominent and strongly translucent veins, and by the undulating to occasionally sinuate leaf margins.

Flowering

November - January

Flower Colours

White

Fruiting

December - March

Propagation Technique

Not known from cultivation.

Threats

Convolvulus verecundus f. glaberrimus occupies an area of about 12 square metres where there are an estimated 15 plants. Therefore, Heenan & Molloy (2019) recommended that it be assessed as 'Threatened/ Nationally Critical' (Criterion “A” of very small population (natural or unnatural). They note that two of the 'Nationally Critical' A subcriteria also apply: A(1) < 250 mature individuals and A(3) total area of occupancy ≤ 1 hectare (see Townsend et al. 2008)). Heenan & Molloy (2019) considred that the qualifier 'DP' (data poor) and 'OL' (one location) apply. This is because there is
no population trend data, and the race is known from only the one location.

Endemic Taxon

Yes

Endemic Genus

No

Endemic Family

No

This page last updated on 5 Sep 2019