Ophioglossum petiolatum
Common names
stalked adder’s tongue fern
Biostatus
Native
Category
Vascular
Structural class
Ferns
Flower colours
No flowers
Detailed description
Perennial, seasonally dormant, firmly fleshy plants forming extensive patches in ideal conditions. Rhizomes erect, glabrous, loosely covered in fleshy white to pale yellow sheaths. Roots fleshy, proliferous. Sterile blade on short stalk up to 30 mm long, yellow-green to dark green. Lamina of sterile blade 15–150 × 6–40 mm, yellow-green to dark green, broadly to narrowly ovate, elliptic, undivided, base truncate to slightly attenuate, venation usually darker than rest of lamina, distinctly reticulate. Fertile spike 14–60 mm long, on stalk 40–200 mm long, bearing 15–48 pairs of sequentially ripening, long-persistent sporangia.
Similar taxa
Ophioglossum coriaceum A.Cunn. which is generally smaller and has a narrower, oval-shaped and stalk-less sterile blade. The fertile spike is much shorter and carries fewer (7–15) pairs of spore-bearing capsules. However the distinction is not quite as clear cut and some populations with the sterile blade form of O. coriaceum but sporangia pairs of up to 25 are known. Further work on the status of plants referred to O. petiolatum in New Zealand is needed (see comments by de Lange & Rolfe 2010).
Distribution
Indigenous. Manawatāwhi / Three Kings Islands (Manawatāwhi / Great Island), North Island, South Island, Chatham Islands. Not recently recorded from the South Island. Last recorded from Chatham Island (Rēkohu) in 2007. Still present on Manawatāwhi / Great Island, and locally from Te Paki to Kawhia and Arohaki Lagoon. Probably now extinct at Hokio, near Levin. New Zealand plants appear to belong to a widespread and common tropical species which reaches its southern limits in this country.
Habitat
Recorded from coastal and lowland habitats. A seasonally dormant species of ephemeral wetlands, moist talus and grassy areas, sandy margins of coastal lagoons, herbfields near lake margins, swamps and streams, and damp hollows within podocarp forest. Plants are most conspicuous between spring and late summer, dying down in autumn and winter.
Current conservation status
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2022-2023 using the New Zealand Threat Classification System (NZTCS) – more information about this can be found on the NZTCS website. This report includes replaces all previous NZTCS lists for vascular plants. Previous assessments can be found here.
- Conservation status of vascular plants in Aotearoa New Zealand, 2023. 2024. Peter J. de Lange, Jane Gosden, Shannel P. Courtney, Alexander J. Fergus, John W. Barkla, Sarah M. Beadel, Paul D. Champion, Rowan Hindmarsh-Walls, Troy Makan and Pascale Michel Department of Conservation. Source: NZTCS and licensed by DOC for reuse under the Creative Commons Attribution 4.0 International licence.
2023 | Threatened – Nationally Vulnerable | Qualifiers: RF, SO, Sp
Threats
May be overwhelmed by other plants or pigs. Destruction of suitable habitat or taking over of habitat by adventive species more able to tolerate changing nutrient status or with greater competitive ability. In cultivation this species is devastated by exotic snails and slugs and this maybe one of the problems for the species in the wild. Plants from two populations (Opuatia and Hokio) proved to be sterile.
Detailed taxonomy
Family
Synonyms
Ophioglossum pedunculosum sensu Allan (1961), O. reticulatum L.
Endemic taxon
No
Endemic genus
No
Endemic family
No
Ecology
Flowering
October—December
Fruiting
November—January
Propagation technique
Easily grown by the division of whole plants. Does best in a fertile soil kept permanently moist (but not saturated). Will tolerate full sun but does better in semi-shade. Intolerant of competition from taller faster growing plants and very vulnerable to slug and snail browsing. This species makes an interesting and unusual pot plant. So far most New Zealand plants that have been investigated in detail have proved sterile. The sterility of the plants examined brings into question the exact status of plants attributed to this species in New Zealand.
Wetland plant indicator status rating
Information derived from the revised national wetland plant list prepared to assist councils in delineating and monitoring wetlands (Clarkson et al., 2021 Manaaki Whenua – Landcare Research Contract Report LC3975 for Hawke’s Bay Regional Council). The national plant list categorises plants by the extent to which they are found in wetlands and not ‘drylands’. The indicator status ratings are OBL (obligate wetland), FACW (facultative wetland), FAC (facultative), FACU (facultative upland), and UPL (obligate upland). If you have suggestions for the Wetland Indicator Status Rating, please contact: [Enable JavaScript to view protected content]
FACW: Facultative Wetland
Usually is a hydrophyte but occasionally found in uplands (non-wetlands).
Other information
Etymology
ophioglossum: Snake’s tongue; from the Greek ophis and glossa; appearance of the fertile leaf
NVS code
The National Vegetation Survey (NVS) Databank is a physical archive and electronic databank containing records of over 94,000 vegetation survey plots - including data from over 19,000 permanent plots. NVS maintains a standard set of species code abbreviations that correspond to standard scientific plant names from the Ngä Tipu o Aotearoa - New Zealand Plants database.
OPHPET
Chromosome number
Meiosis irregular
Previous conservation statuses
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2022-2023 using the New Zealand Threat Classification System (NZTCS) – more information about this can be found on the NZTCS website. This report includes replaces all previous NZTCS lists for vascular plants. Previous assessments can be found here.
- Conservation status of vascular plants in Aotearoa New Zealand, 2023. 2024. Peter J. de Lange, Jane Gosden, Shannel P. Courtney, Alexander J. Fergus, John W. Barkla, Sarah M. Beadel, Paul D. Champion, Rowan Hindmarsh-Walls, Troy Makan and Pascale Michel 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: RF, SO, Sp
2012 | Threatened – Nationally Critical | Qualifiers: RF, SO, Sp
2009 | Threatened – Nationally Critical | Qualifiers: RF, SO, Sp
2004 | Threatened – Nationally Endangered
Referencing and citations
References and further reading
Brownsey PJ. 1985. Ophioglossum petiolatum at Hokio beach. Wellington Botanical Society Bulletin 42: 33–34.
Brownsey PJ, Smith-Dodsworth JC. 2000. New Zealand Ferns and Allied Plants. David Bateman, Auckland, NZ. 168 p.
Chinnock RJ. 1998. Ophioglossaceae. Flora of Australia 48, Ferns Gymnosperms and allied groups: 99–109. ABRS/CSIRO Victoria, Australia.
de Lange PJ. 1988. Ophioglossum petiolatum Hook in a reserve near Kawhia. Wellington Botanical Society Bulletin 44: 4–7.
de Lange PJ, Heenan PB, Norton DA, Rolfe JR, Sawyer JWD. 2010. Threatened Plants of New Zealand. Canterbury University Press, Christchurch. 471 p.
de Lange PJ, Rolfe JR. 2010. New Zealand indigenous vascular plant checklist. New Zealand Plant Conservation Network, Wellington, NZ. 131 p.
Attribution
Fact sheet prepared by P.J. de Lange 2004 (Updated 21 March 2011). Description based on de Lange et al. (2010).
NZPCN Fact Sheet citation
Please cite as: de Lange, P.J. (Year at time of access): Ophioglossum petiolatum Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/ophioglossum-petiolatum/ (Date website was queried)