A Brief Guide to
Native New Zealand Carnivorous Plants
Native New Zealand Carnivorous Plants
New Zealand has a number of native carnivorous plants, most of which are also found elsewhere. However, there are several species which are endemic to New Zealand. Most of the plants live in wetlands and particularly in spagnum bogs - a good way see many of our native carnivorous plants is to take a trip to Fiordland National Park and find a spagnum bog. In his book "A Guide to Carnivorous Plants of the World", Gordon Cheers describes a trip to Arthur's Pass in the South Island, and waxes quite lyrical about seeing Utricularia monanthos, Drosera spathulata and D. arcturi in the wild.
New Zealand's native carnivorous plants fall into two main groups: sundews (Drosera spp) and bladderworts (Utricularia spp).
Note: this page was originally written in 1998. Bruce Salmon has excellent book Carnivorous Plants of New Zealand, which I highly recommend.
Drosera:
New Zealand has six native species of sundew, three of which are alpine; five of the six native species (all except D. stenopetala) are also native to Australia.
The Maori for sundew is wahu (wah-hoo).
| D. arcturi | Originally described by Hooker in 1834. Found in all three main islands of New Zealand, D. arcturi is an alpine plant with greenish, strap-shaped leaves about 3-6cm long. The plant typically produces one or more flower stalks, producing a flower with five white petals and prominent dark green sepals. Normally found growing in montane to low alpine regions, 300 - 1,500 metres above sea level, D. arcturi is usually found in peat bogs, or around the edges of tarns (small alpine ponds). During winter, D. arcturi dies back to a nesting bud. The name comes from Mount Arthur, in Tasmania, which is the type location. |
| D. auriculata, aka D. peltata ssp auriculata | This sundew has a rosette of trapping leaves prostrate on the ground, from which emerges an erect stem up to 70cm (normally 10 - 30cm), with greenish/reddish leaves coming off. D. auriculata is found in the North Island and the top end of the South Island. D. auriculata grows in bogs, acid soils, and so on, and also in sunny clay banks. A tuberous sundew, D. auriculata dies back during the summer. |
| D. binata ("Scented sundew") | Spread out across the country, D. binata is normally found in bogs or swamps - or, in many cases, in roadside drainage ditches. Each leaf divides in two, producing a characteristic "tuning fork" shape. Growing to a reasonable size (up to 50cm), D. binata is the most common and obvious sundew found in NZ. |
| D. pygmaea ("Pygmy sundew") | As the name suggests, D. pygmaea is tiny, averaging about 1cm in diameter. It is found in the North and South Islands, particularly in the areas around Waiouru and in Fiordland. D. pygmaea produces gemmae at the end of summer, and spreads quickly, so that a mass of tiny individual plants can take on the appearance of a glistening red carpet. |
| D. spathulata ("Spoon-shaped sundew") | Found throughout the country at elevations ranging from lowland (in the far South) to low alpine (to 1,400 metres), D. spathulata is considered to be an alpine sundew. It is somewhat smaller than D. arcturi or D. stenopetala (up to 5cm in diameter), and has a characteristic pair of tiny brown stipules (up to 7mm) at the leaf base. D. spathulata is often found with other sundews, generally in acid soils or peat bogs. Flowering from November to January, generally only one or two flower stalks are borne (plants growing at higher altitudes generally only produce one flower stalk), but often multiple flowers are borne on a single stalk. "Spathulata" refers to the shape of the leaves, as does the common name. |
| D. stenopetala | First described by Hooker in 1834. The leaves are a dark or reddish-green, with rounded ends. D. stenopetala has a similar habitat and distribution to D. arcturi, although as with D. spathulata it can be found at low levels in the far South. It likes wet depressions in areas of sub-alpine vegetation, and has been seen on avalanche chutes below the treeline. Allan (1961) comments that D. stenopetala "varies considerably in size according to habitat conditions." (p201) "Stenopetala" refers to the narrow petals of the flowers. |
Other Drosera
W. Colenso, an English-born botanist who worked in New Zealand from 1834 until his death in 1899, was an enthusiastic describer of species. Leaving aside his influence on the taxonomy of our native bladderworts, he described numerous species of sundew which are now regarded as dubious, due to a lack of type specimens (in some cases, such as D. atra, he described a new species based on a single specimen). Allan (1961) describes nine of the species described by Colenso as being incertae sedis, "of uncertain position", a polite way of saying that he doubted the legitimacy of Colenso's species. Colenso described a further nine species to those currently accepted to be in New Zealand; a list of these species, followed by an attempt to guess as to which species he was really talking about runs thus:
- D. atra - D. arcturi.
- D. circinervia - D. auriculata.
- D. flagellifera - D. binata.
- D. ligulata - D. arcturi.
- D. minutula - D. pygmaea.
- D. polyneura - D. arcturi.
- D. ruahinensis - D. arcturi.
- D. stylosa - D. auriculata.
- D. triflora - D. spathulata
Utricularia
There are a total of nine recorded native species of Utricularia, of varying degrees of rarity. The taxonomic status of four of the species (U. colensoi, U. mairii, U. subsimilis and U. volcanica) is doubtful, while another two (U. delicatula and U. laterifolia) are mildly contentious.
| Australis ("Yellow Bladderwort"), aka U. protrusa | An aquatic bladderwort normally found in slow-moving or still water. The plants float on the surface of the water, with submerged leaves. The traps are roughly 4mm across, and emerge from a long central stem (30 - 90cm). During winter, U. australis forms resting buds and sinks, to reemerge again in Spring. Sulphur yellow flowers are borne on 15-20cm scapes, appearing from spring to late summer. |
| Colensoi | First described by Hooker in his Handbook of the New Zealand Flora (1864), as being very similar to U. novae-zelandiae, but with differing flowers. The type specimens were preserved in "camphorated spirits of wine" (!), and were lost, along with the original type specimens for U. protrusa. This species' taxonomic status is doubtful, to say the least. |
| Delicatula | Occurs in bogs in the northern North Island. It is sometimes regarded as a subspecies of U. lateriflora. |
| Lateriflora | Found in the northern half of the North Island, but is very rare. The bladders are less than 1mm in diameter. A terrestrial bladderwort, U. laterifolia is found in lowland bogs. The flowers are usually borne in clumps of two or three, and are a pale lilac or lavender with a white 'eye'. It is worth noting that Allan (1961) expresses dubiousness as to the identification of this species (a common Australian/Tasmanian plant), as he feels that the type specimens in NZ differ from the described Australian specimens. |
| Mairii | Only collected in 1872, in Lake Rotomahana, and not seen since the Tarawera eruption of 1886. This species was known only from the original type specimens, and was described by Kirk (in Transactions of the New Zealand Institute 5, 1873, p343) as resembling U. intermedia, "but the bladders are attached to the leaves". The type specimens had sparingly branched stems 5-15cm long, with leaves up to 1cm and bladders about 2mm across. Now thought to be extinct. |
| Monanthos ("Purple Bladderwort") | U. monanthos was first described in 1860, in Tasmania. U. monanthos is a small plant with narrow leaves from 5 - 20 mm in length. The flowers are large and colourful (bright purple with a yellow centre), borne on long, slender stalks. Found throughout the country, U. montanthos is more common in the South, and is an alpine plant. In the South, it can be found at low elevations, but it is more common in low alpine conditions (to 1,400 metres elevation). Like most terrestrial Utricularia, it is rather dull looking unless it is in flower - but a large patch of U. monanthos in flower is generally agreed to be an extremely pretty sight. John Salmon, in "Field Guide to the Alpine Plants of New Zealand", describes seeing U. monanthos flowering in the thousands as being "an unforgettable sight." It prefers peat bogs, where it tends to grow in large mats. "Monanthos" means "single-flowered". |
| Novae-zealandiae | North Island and Western South Island, generally in boggy grown in lowlands to lower montane regions. U. novae-zealandiae has short (1.5cm), fan-shaped leaves. The flowers are purple-violet, with vertical yellow lines on the palate. |
| Subsimilis | Originally described by Colenso in Transactions of the New Zealand Institute 16 (1884), p334. It was described as having 2-3 roughly spathulate leaves, growing from the base. The flower was said to be purple, with a circular lower lip, and borne on a 2 - 3 1/2" scape. The type specimens orginally came from Taupo. Colenso also remarked that the species was very similar to U. laterifolia. Cheeseman (1925) regarded this as being simply a synonym for U. novae-zelandiae. |
| Vulcanica | Orignally described by Colenso in Transactions of the New Zealand Institute 26 (1894), p318. Cheeseman (1925: 848) regards this as being a synonym for U. colensoi, which is in turn regarded as probably being synonmymous with U. novae-zeladiae. |
Introduced Species: |
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| Biflora | Easily confused with U. australis, this was introduced from North America. |
| Gibba | U. gibba is well known internationally for being an easy plant to grow in aquaria. Partially aquatic, partially terrestrial, U. gibba grows very well and very quickly. Unfortunately, these tendencies have combined in New Zealand; U. gibba does extremely well in our waterways - to the point where it has been declared a noxious weed. MAF is not happy about this, and would like to find out who released it into our waterways in the first place. |
Cultivation:
The following are cultivation tips from members of the NZCPS. Thanks go to Bruce Salmon for allowing his cultivation tips to be reproduced here.
- D. stenopetala:
- As for D. arcturi but seed is difficult to germinate
( I have not been able to germinate it here in Auckland.) Maybe
it needs to be snap frozen first?
Both species can't be grown in Auckland for more than about 3 years. They gradually get smaller and die. Temps here are Summer: 25C+Day - 18C at night. Winter: 15C Day - 6C with the odd frost overnight.
Bruce Salmon
Bibliography
- Allan, H. H. (1961). Flora of New Zealand Volume One. Wellington: Government Print.
- Cheers, G. (1992). A Guide to Carnivorous Plants of the World. Prymble: Angus & Robertson.
- Coffey, B. T. and Clayton, J. S. (1988). New Zealand Waterplants. Hamilton: MAF New Zealand.
- Johnson, P. and Brooke, P. (1989). Wetland Plants in New Zealand. Wellington: DSIR Publishing.
- Mark, A. F. and Adams, N. (1973). New Zealand Alpine Plants. Wellington: A H & A W Reed.
- Moore, L. B. and Irwin, J. B. (1978). The Oxford Book of New Zealand Plants. Wellington: Oxford University Press.
- Pietrapaolo, J. and P. (1986). Carnivorous Plants of the World. Portland: Timber Press.
- Salmon, J. T. (1968). Field Guide to the Alpine Plants of New Zealand. Wellington: A H & A W Reed.
- Walker, Rick (ed) (1998) Carnivorous Plant Database. Url: http://www.labs.agilent.com/bot/cp_home.