Leptospermum repo
Common name
Waikato peat bog mānuka
Family
Myrtaceae
Flora category
Vascular – Native
Endemic taxon
Yes
Structural class
Trees & Shrubs - Dicotyledons
Current conservation status
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2017 using the New Zealand Threat Classification System (NZTCS) – more information about this can be found on the NZTCS website. This report includes a statistical summary and brief notes on changes since 2012 and replaces all previous NZTCS lists for vascular plants.
Please note, threat classifications are often suggested by authors when publications fall between NZTCS assessment periods – an interim threat classification status has not been assessed by the NZTCS panel.
- Conservation status of New Zealand indigenous vascular plants, 2017 . 2018. Peter J. de Lange, Jeremy R. Rolfe, John W. Barkla, Shannel P. Courtney, Paul D. Champion, Leon R. Perrie, Sarah M. Beadel, Kerry A. Ford, Ilse Breitwieser, Ines Schönberger, Rowan Hindmarsh-Walls, Peter B. Heenan and Kate Ladley. Department of Conservation. Source: NZTCS and licensed by DOC for reuse under the Creative Commons Attribution 4.0 International licence.
2017 | Threatened – Nationally Critical | Qualifiers: DP, De
Distribution
Endemic. New Zealand. North Island, greater Waikato lowlands, Coromandel Peninsula and Bay of Plenty (historically Northland and Taranaki).
Habitat
Restiad bog and associated wetlands
Detailed description
Shrub to small tree (1)−3−(6)m tall, sometimes much reduced in extreme acid wetlands, then attaining heights of 100 mm or less. Trunk usually unbranched at base, up to 0.1 m d.b.h, usually devoid of branches in lower ⅓ to ½. Bark firmly attached, fibrous, often deeply fissured. Branches usually 3 or more, and openly branching with semi-erect to widely spreading branches, young stems copiously covered in (0.12−0.24)–0.48−(0.80) mm long, white, straight to slightly flexuous, sericeous, antrorse-appressed hairs, becoming glabrescent with age. Vegetative buds 3−8, mostly shedding soon after vegetative growth commences, rarely with a few persistent, (0.4)−0.6−0.8−(1.0) × (0.3)−0.5−0.7−(0.9) mm, amber to red-brown, scarious, oblong to ovoid, inner surface smooth, glossy, outer with frayed, lacerate margins or entire, basal portion densely invested in white antrorse-appressed to suberect sericeous hairs up to 0.01 mm long. Leaves pleasantly spicy-scented when crushed, divergent to spreading, (5.0)−8.0−11.0−(15.0) × (0.3)−0.5−0.8−(2.0) mm, glossy yellow-green, green to dark green; lamina linear, linear-lanceolate, narrowly lanceolate, occasionally filiform, flat to weakly concave, acute, minutely cuspidate, bases narrowly cuneate, margins minutely denticulate; surfaces sericeous hairy near base and along midrib, and proximal ⅓ of leaf margin, glabrescent with hairs ± persisting on basal portion of leaf and; oil glands numerous, more evident when dry. Perules 4−6, shedding at bud burst, (0.4)−0.6−0.8−(1.0) × (0.4)−0.6−0.8−(0.9) mm, glabrous, hyaline, amber to pale red-brown, scarious, orbicular, margins usually entire, sometimes frayed inner surface smooth, glossy. Inflorescence monadic on short axillary brachyblasts, or, on occasion on long, 200 mm long or more, terminal shoots. Prophylls caducous, 2, 0.1−0.2 mm long, oblong, midrib scarcely developed, yellow-green, green to red-green when fresh, tan when dry, abaxial surface densely invested in white sericeous hairs. Pedicels sessile, or 0.1 mm long at anthesis, elongating to 2.4 mm after anthesis, terete, sparsely invested with antrorse-appressed, sericeous white hairs. Flower buds clavate, tholiform with calyx lobes not meeting. Fresh flowers when fully expanded 10−11−(15) mm in diameter. Hypanthium (2.8)−3.0−(4.0) × (1.6)−2.2 −(4.0) mm, green or honey-brown, obconic, obconic-funnelform; terminating in a slightly thicker rim bearing five calyx lobes; surface smooth (wrinkling in dry specimens) finely glandular punctate, glabrous. Calyx lobes 5, spreading, 2.4−2.6 × 2.4−2.6 mm, caducous, broadly deltoid with rounded apices, usually glabrous except for margins which may be sparsely ciliate, oil glands colourless. Receptacle dark red at anthesis. Petals 5, spreading, 4−5 × 2−3 mm, white, orbicular, apex obtuse to rotund, margins finely crimped, oil glands not evident. Stamens 15−36, in 1−2 weakly defined whorls adnate to receptacular rim, filaments white. Antipetalous stamens 3(+2), antisepalous 4−6. Outermost antipetalous stamens erect or weakly incurved, on filaments 1.20−1.68 mm long, occasional inner whorl of 2 stamens present, these erect or incurved, 0.9−1.2 mm long, positioned at base of the outermost antipetalous pair. Antisepalous stamens about half length of antipetalous, on filaments 0.6−0.84 mm long, incurved, erect or in mixtures of both. Anthers dorsifixed 0.36 × 0.12 mm, ovoid, latrorse. Pollen white to cream. Anther connective gland 0.24 mm long, amber, narrowly obovoid. Ovary 5-locular, each loculus with c. 80 ovules, set in 8 rows on each placental lobe. Style (0.96)−1.9−2.0 mm long at anthesis, elongating to 3 mm after anthesis, green (very rarely pink—one population); stigma 0.70−0.78 mm in diameter at anthesis, expanding to 0.9 mm following anthesis, flat, green, sometimes flushing pink at anthesis, finely papillate rugulose. Fruits persistent, woody, (5)−8−(9) × (5)−6 mm, pale brown-grey to grey, hemispherical / globose (sometimes broadly obconic), centre often with persistent style remnant, valves 5, exserted as a dome, indented at centre, ± symmetrical with base. Valves opening on dead branches or following fire. Seeds 2.3−2.4−(2.6) × 0.24− 0.24 mm, linear, linear-cuneiform, curved, flexuous to sigmoid, laterally compressed or terete, 2−4-angled, apex truncate or acute, testa dull or glossy, orange-brown, glabrous, longitudinally striate.
Manaaki Whenua Online Interactive Key
Similar taxa
From Leptospermum scoparium s.s., L. repo differs ecologically by its restriction to peat bog habitats, and morphologically by its gracile growth habit; longer, finer, linear, linear-lanceolate leaves, and larger flowers which have white petals, usually white stamen filaments and usually green style and stigma. Leptospermum scoparium s.s. has smaller flowers, which may have pink-tinged petals, usually pink-tinged or pink stamen filaments, and pink-tinged, pink or carmine coloured style and stigma; the leaves of L. scoparium s.s. are broadly ovate, oval to orbicular and sharply acuminate. Leptospermum repo is allied to three other northern New Zealand Leptospermum, only one of which is formally recognised, L. scoparium var. incanum. From that variety L. repo is by its much narrower, linear, linear-lanceolate leaves, that are only sparsely hairy – broadly lanceolate, and densely covered in hairs when young, and notably by its smaller, white rather than larger, usually pink tinged, pink or even red flowers (for other differences see de Lange & Schmid 2021).
Flowering
October–January
Flower colours
White
Fruiting
Fruits are found throughout the year.
Propagation technique
Easily grown from fresh seed. Leptospermum repo is an attractive species on account of its gracile growth habit, fine, linear, linear-lanceolate leaves, and floriferous habit.
Threats
Leptospermum repo has been eliminated from all but c. 10% of its former wetland habit (it now seems to be extinct in Northland and Taranaki). Decline is still ongoing in some of the peat bogs in which remnant populations persist as a result of farming, roading and on going. The species remains common in the larger, intact peat bogs (e.g., Whangamarino, Kopouatai). One serious threat to the species is myrtle rust diseases caused by the naturalised Austropuccinia psidii. Although this rust has yet to be observed on Leptospermum repo it is believed only to be a matter of time before it does attack this species. For this reason, L. repo, as Leptospermum aff. scoparium (c) (AK 191319; “Waikato peat bog”) was listed by de Lange et al. (2018) as “Threatened / Nationally Critical” qualified “DP [Data Poor]”, “De [Designated’]”. In their paper, de Lange & Schmid (2021) saw no reason to change that status, though L. repo should also be qualified “Rel [Relict]” considering its historic loss.
Etymology
leptospermum: Slender seed
repo: The epithet “repo” is taken from Te Reo Māori (Māori Language) for “swamp”; it refers to the wetland habitat in which Leptospermum repo grows
Attribution
Fact sheet prepared for NZPCN by P.J. de Lange 30 August 2021. Description from de Lange & Schmid (2021).
References and further reading
de Lange PJ, Schmid LMH. 2021. Leptospermum repo (Myrtaceae), a new species from northern Aotearoa / New Zealand peat bog habitats, segregated from Leptospermum scoparium s.l. Ukrainian Botanical Journal 78(4): 247–265. https://doi.org/10.15407/ukrbotj78.04.247
de Lange PJ, Rolfe JR, Barkla JW, Courtney SP, Champion PD, Perrie LR, Beadel SM, Ford KA, Breitwieser I, Schönberger I, Hindmarsh-Walls R, Heenan PB, Ladley K. 2018. Conservation status of New Zealand indigenous vascular plants, 2017. New Zealand Threat Classification Series 22. Department of Conservation, Wellington, NZ. 82 p. https://www.doc.govt.nz/globalassets/documents/science-and-technical/nztcs22entire.pdf.
NZPCN Fact Sheet citation
Please cite as: de Lange, P.J. (Year at time of access): Leptospermum repo Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/leptospermum-repo/ (Date website was queried)