Pyrrosia serpens
Biostatus
Native
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 Critical | Qualifiers: DPS, DPT, OL, SO
Category
Vascular
Structural class
Ferns
Simplified description
Creeping fern with simple, leathery, lanceolate to oblong fronds, with sori arranged in one row either side of frond midrib.
Detailed description
Low epiphytic fern. Rhizomes long-creeping, 1–1.5 mm diameter, densely scaly. Rhizome scales peltate, ovate, 2–2.8 mm long, 0.7–0.9 mm wide, appressed, dark brown centrally, becoming orange-brown and colourless on the margin; margins dentate to ciliate. Fronds undivided; the sterile narrowly elliptic, 90–110 mm long (including stipe), 9–15 mm wide; the fertile narrowly elliptic to narrowly ovate or narrowly oblong, 115–175 mm long (including stipe), 7–10 mm wide; apex acute to obtuse, margins entire, base attenuate to an indistinct stipe, dark green, coriaceous to succulent, scattered stellate hairs on adaxial surface, densely covered in mostly silver-coloured stellate hairs on abaxial surface. Sori slightly elongate, 3–5 mm long, sunken in the lamina and sometimes protuberant on adaxial surface, arranged in one row either side of midrib, not confluent, confined to distal part of lamina, exindusiate, paraphyses present as stellate hairs. (Description from Brownsey et al. (2021)).
Similar taxa
The fronds of Pyrrosia serpens are narrowly oblong whereas those of P. elaeagnifolia are broadly ovate or elliptic. The rhizome scales of P. serpens are appressed, ovate in outline, 2–2.8 mm long, slightly ciliate, and have a conspicuous dark centre, whereas those of P. elaeagnifolia are squarrose, narrowly ovate in outline, 2–7 mm long, entire, and concolorous. Critically, the arrangement of the sori differ. In P. serpens, they are large, arranged in one row either side of the midrib, often partly sunken into the lamina and somewhat protuberant on the adaxial surface, whereas in P. elaeagnifolia they are in 2–5 rows, superficial on the abaxial surface and not protuberant on the adaxial side.
Distribution
Indigenous. New Zealand: northern Kermadec Islands (Dayrell Island, Herald Islets). Otherwise Fiji, Cook Islands, Society Islands, Austral Islands, Gambier Islands, Pitcairn Island, Henderson Island.
Habitat
In the New Zealand Botanical Region known only from the Kermadec Islands from a single collection made from the basal trunk of Metrosideros kermadecensis.
Threats
Brownsey et al. (2021) reported the presence of this species in the New Zealand Botanical Region on the basis of one collection made from Dayrell Island, Herald Islets, northern Kermadec Islands group (de Lange & Blanchon 2021). That specimen was collected in 2011 and at the time it was not recognised as being distinct from P. elaeagnifolia. As very little is known about it, for now the species was assessed as ‘Data Deficient’ in the region. It may yet be present on the other Kermadec Islands though critical collecting of Pyrrosia in 2009 and 2011 failed to find further populations of this species.
Detailed taxonomy
Genus
Family
Endemic taxon
No
Endemic genus
No
Endemic family
No
Other information
Etymology
pyrrosia: Flame coloured; from the Greek purros; the colour of the hairs on its leaves
serpens: Derived from Latin ‘serpens’, present active participle of serpo (“crawl, creep”).
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.
PYRSER
Referencing and citations
References and further reading
Brownsey PJ, Shepherd LD, de Lange PJ, Perrie LR. 2021. Pyrrosia serpens (G.Forst.) Ching, a new record for the fern flora of the Kermadec Islands. New Zealand Journal of Botany 59(2): 229–243. https://doi.org/10.1080/0028825X.2020.1796716.
de Lange PJ, Blanchon DJ. 2021. The flora and vegetation of Dayrell Island, Herald Islets, northern Kermadec Island group. Records of the Auckland Museum 55: 37–52.
Attribution
Fact Sheet prepared for NZPCN by P.J. de Lange (12 October 2022). Description based on Brownsey et al. (2021).
NZPCN Fact Sheet citation
Please cite as: de Lange, P.J. (Year at time of access): Pyrrosia serpens Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/pyrrosia-serpens/ (Date website was queried)