The forest ringlet (''Dodonidia helmsii''), also known as Helms' butterfly, is a rare
butterfly
Butterflies are insects in the macrolepidopteran clade Rhopalocera from the Order (biology), order Lepidoptera, which also includes moths. Adult butterflies have large, often brightly coloured wings, and conspicuous, fluttering flight. The ...
of the
family
Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...
Nymphalidae endemic
Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsew ...
to
New Zealand
New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island count ...
. It is the only species in the genus ''Dodonidia''.
Taxonomy
The forest ringlet was first described by
Richard William Fereday
Richard William Fereday (c.1820–30 August 1899) was a New Zealand lawyer, entomologist and artist. He was born in Ettingshall, Staffordshire, England
England is a country that is part of the United Kingdom. It shares land borders wit ...
from a specimen collected in the
Paparoa Range
The Paparoa Range is a mountain range in the West Coast Region, West Coast region of New Zealand's South Island. It was the first New Zealand land seen by a European – Abel Tasman in 1642. Part of the range has the country's highest protection ...
by a Mr R. Helms of
Greymouth. Fereday gave it the
specific name Specific name may refer to:
* in Database management systems, a system-assigned name that is unique within a particular database
In taxonomy, either of these two meanings, each with its own set of rules:
* Specific name (botany), the two-part (bino ...
''helmsi'', but would not speculate as to its genus. The species was properly named in 1884 by
Arthur Gardiner Butler, who coined the genus ''Dodonidia'', from its resemblance to the Asian
''Dodona'' butterflies, and corrected the spelling of the species name to ''D. Helmsii'' (now ''D. helmsii'').
Because it was named after Helms, it is properly known as "Helms' butterfly", although this is often misspelled as "Helm's butterfly". The name "forest ringlet" is more commonly used.
Ecology
The forest ringlet caterpillar is nocturnal and feeds on "cutty grass" (''
Gahnia
''Gahnia'' (sawsedge, saw-sedge) is a genus of sedges native to China, Southeast Asia, New Guinea, Australia, New Zealand and a number of Pacific Islands. The common name is due to the toothed margins. It often forms tussocks.
Species
Accept ...
'') and bush snowgrass (''
Chionochloa
''Chionochloa'' is a genus of tussock grass in the family Poaceae, found primarily in New Zealand with one known species in New Guinea and another on Lord Howe Island (part of Australia). Some of the species are referred to as snowgrass.
Most of ...
'') from spring to early autumn. Adults live for three or four weeks and are fast-flying, found in January and February in clearings or near forest edges, mainly in beech (''
Nothofagus'') forest north of about
Lewis Pass
Lewis Pass (el. 907 m.) is a mountain pass in the South Island of New Zealand.
The northernmost of the three main passes across the Southern Alps, it is higher than the Haast Pass, and slightly lower than Arthur's Pass. State Highway 7 traver ...
.
Conservation
''Dodonidia helmsii'' was once widespread in New Zealand, including the Wellington and Auckland area, but has become significantly rarer over the last 50 years.
There are two causes: the increasing rarity in lowland areas of the sedges that are its food plant, and the introduction of predatory
wasp
A wasp is any insect of the narrow-waisted suborder Apocrita of the order Hymenoptera which is neither a bee nor an ant; this excludes the broad-waisted sawflies (Symphyta), which look somewhat like wasps, but are in a separate suborder. Th ...
s to New Zealand that prey on its
larva
A larva (; plural larvae ) is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle.
The ...
e. Forest ringlets have disappeared from forest below 400 m altitude, but are still found at 600 m or higher, the altitudinal limit for the
German
German(s) may refer to:
* Germany (of or related to)
**Germania (historical use)
* Germans, citizens of Germany, people of German ancestry, or native speakers of the German language
** For citizens of Germany, see also German nationality law
**Ger ...
and
common wasps. This species has been classified as having the "At Risk, Relict" conservation status under the
New Zealand Threat Classification System
The New Zealand Threat Classification System is used by the Department of Conservation to assess conservation priorities of species in New Zealand.
The system was developed because the IUCN Red List, a similar conservation status system, had some ...
.
See also
*
Butterflies of New Zealand
References
External links
* The forest ringlet discussed on RNZ ''Critter of the Week''
23 September 2016Forest Ringlet Butterfly Project fundraising for research into ''D. helmsii'' decline
{{Taxonbar, from=Q773434
Butterflies of New Zealand
Dodonidia
Butterflies described in 1884
Endemic fauna of New Zealand
Taxa named by Arthur Gardiner Butler
Endangered biota of New Zealand
Endemic insects of New Zealand