Geranium sessiliflorum var. arenarium
Common names
short-flowered cranesbill
Biostatus
Native – Endemic taxon
Category
Vascular
Structural class
Herbs - Dicotyledons other than Composites
Flower colours
White
Detailed description
All parts softly and finely pilose. Leaves orbicular, closely lobed, divided at base, unusually appressed to the ground, petioles and peduncles tinged with purple, blade pale glaucous grey. Flowers white.
Similar taxa
Most similar to G. brevicaule Hook.f. from which it differs mainly by the softly silvery-pilose, glaucescent to silvery leaves which are slightly larger in size. The flowers appear to be smaller. A poorly known taxon whose exact status requires further clarification. It does, however, appear to be distinct from the other variants now included in G. brevicaule.
Distribution
Endemic. South Island, South of Otago Peninsula throughout the Foveaux Strait area and in northern Stewart Island/Rakiura.
Habitat
Coastal. Mainly found in sand country—usually in dune swales or on shallowly sloping beaches. Sometimes on or near rock outcrops or within peaty soils near seepages or within coastal turfs.
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.
Please note, threat classifications are often suggested by authors when publications fall between NZTCS assessment periods – these interim threat classification statuses has not been assessed by the NZTCS panel.
- 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 | At Risk – Declining | Qualifiers: CD, DPS, DPT, RR
Threats
Never that common at any particular location and yet occupies a large range. At risk in its preferred sand dune habitats from the spread of marram grass (Ammophila arenaria) and other weeds.
Detailed taxonomy
Family
Geraniaceae
Synonyms
Geranium sessiliflorum subp. novae-zelandiae var. arenarium (G.Simpson et J.S.Thomson) Carolin
Taxonomic notes
Allan (1961) treats G. brevicaule Hook.f. as a synonym of G. sessiliflorum var. arenarium, incorrectly stating that the type locality of G. brevicaule is Chalky Inlet, Fiordland, New Zealand when it is Tasmania (Aedo et al. 2005). Fiordland plants appear to match G. sessiliflorum var. arenarium, and together with plants from Stewart Island, the Foveaux Strait and coastal portion of Otago these plants do not fit closely any of the other plants within New Zealand or Australia now attributed to G. brevicaule (cf. Aedo et al. 2005). Therefore pending further study NZPCN prefer to regard this variety as distinct from G. brevicaule (see also Mitchell et al. 2009), and as it has no published rank yet within that species, we use the only published name available for it, G. sessiliflorum var. arenarium.
Endemic taxon
Yes
Endemic genus
No
Endemic family
No
Ecology
Flowering
October–March
Fruiting
December–June
Propagation technique
Easily grown from seed. An excellent pot plant. Does well in full sun in a free-draining substrate.
Other information
Etymology
geranium: From the Greek geranos ‘crane’, the fruit of the plant resembling the head and beak of this bird, hence the common name cranesbill.
sessiliflorum: With unstalked flowers
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.
GERSVA
Chromosome number
2n = 52
Previous conservation statuses
2017 | At Risk – Declining | Qualifiers: CD, DP, RR
2012 | At Risk – Declining | Qualifiers: DP, RR
2009 | At Risk – Declining | Qualifiers: DP, RR
2004 | Not Threatened
Referencing and citations
References and further reading
Aedo C, Navarro C, Alarcón ML. 2005: Taxonomic revision of Geranium sections Andina and Chilensia (Geraniaceae). Botanical Journal of the Linnean Society 149: 1–68. https://doi.org/10.1111/j.1095-8339.2005.00432.x
Allan HH. 1961. Flora of New Zealand, Volume I. Indigenous Tracheophyta: Psilopsida, Lycopsida, Filicopsida, Gymnospermae, Dicotyledones. Government Printer, Wellington, NZ. 1085 p.
Mitchell AD, Heenan PB, Paterson AM. 2009. Phylogenetic relationships of Geranium species indigenous to New Zealand. New Zealand Journal of Botany 47: 21–31. https://doi.org/10.1080/00288250909509789
Attribution
Fact Sheet prepared by P.J. de Lange (28 July 2007).
NZPCN Fact Sheet citation
Please cite as: de Lange, P.J. (Year at time of access): Geranium sessiliflorum var. arenarium Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/geranium-sessiliflorum-var-arenarium/ (Date website was queried)