Percnodaimon

Last updated

Percnodaimon
MA I582944 TePapa Percnodaimon-merula-Hewitson full.jpg
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Lepidoptera
Family: Nymphalidae
Genus: Percnodaimon
Butler, 1876
Species:
P. merula
Binomial name
Percnodaimon merula
(Hewitson, 1875)
Synonyms
  • Erebia plutoFereday, 1872
  • Erebia merulaHewitson, 1875
  • Percnodaimon plutoButler, 1876
  • Oreina othelloFereday, 1876

Percnodaimon merula, the black mountain ringlet, is a satyrid butterfly in the family Nymphalidae. It is currently the only recognised species in the monotypic genus Percnodaimon, endemic to New Zealand, although there may be other undescribed species in the genus. The black mountain ringlet is notable for living exclusively in rocky areas of New Zealand's Southern Alps, usually above 1200 m. Its eggs are laid on rocks, its larvae feed on mountain Poa species, and it pupates under a stone. It has distinctive dark velvety wings and a zig-zag flight pattern over the scree slopes on which it lives.

Contents

Taxonomy

This species has had a complicated taxonomic history. It was originally described as Erebia pluto by Richard W. Fereday in 1872 from the Craigieburn Range in the South Island, [1] and was moved to the new genus Percnodaimon by Butler in 1876. [2] It was known as Percnodaimon pluto for many years, and Wise in 1967 regarded this as the correct name for the species, [3] but was eventually synonymised with P. merula, under which name it is usually referred to today.

Most sources consider Percnodaimon monotypic, but in 2012 mitochondrial gene sequencing by Hamish Patrick for his Lincoln University Hons thesis suggested it was a species complex, with up to six species in the genus. [4] In their 2012 guide to South Pacific butterflies, Brian and Hamish Patrick stated there are up to eight species of Percnodaimon still to be described, based on wing shape, pattern, and colour, size, behaviour, and season of emergence. Their species list was as follows: [5]

Although the Patricks stated in 2012 that nuclear DNA was being studied with a view to formally naming and describing these species, [5] as of 2022 that had yet to happen, and P. merula is still considered the only species in the genus.

Its Māori name, pepe pouri, means "dark moth", and is applied to several ringlet species, including the forest ringlet ( Dodonidia helmsii ) and Butler's ringlet ( Erebiola butleri ).[ citation needed ]

Description

Illustration by Des Helmore LEPI Nymphalidae Percnodaimon merula.png
Illustration by Des Helmore

The wingspan of the Percnodaimon imago can be between 35 and 55 mm, and its broad velvety wings are usually black or brown across the dorsal surface, sometimes with a purple reflection. Forewings have characteristic black and white circles inside a patch of brown at their distal ends. There is little sexual dimorphism: males and females are similar in appearance, with females a little larger. The row of large pale spots often found on the underside of the hindwings is more noticeable in females. [5]

Black mountain ringlets fly slowly in zigzag patterns, especially on a sunny day, taking advantage of thermals and often gliding in a "V" position.

"When disturbed this insect flies often with considerable rapidity and thus often eludes the net, so that the capture of a good series of specimens on a rugged mountain-slope is usually very exciting, if not actually dangerous work." —George V. Hudson (1928) [6]

Percnodaimon merula basking in the sun Percnodaimon merula 1179344.jpg
Percnodaimon merula basking in the sun

Wing colour plays an important physiological role: the dark wings with a large surface area absorb sunlight and store heat, essentially acting like solar panels, an adaptation to the cool climate of the Southern Alps. The butterfly sits with its wings open and turned towards the sun, flying while the sun is shining and hiding amongst rocks when clouds intervene. [7] At night they shelter deep in rocky crevices. [5]

Distribution

In its usual habitat of scree slopes Percnodaimon merula 59489853.jpg
In its usual habitat of scree slopes

The genus Percnodaimon is restricted to the dry eastern mountains in the South Island of New Zealand, on greywacke scree slopes and amongst rockfalls. [7] It occurs at altitudes ranging from 800 to 2500 metres, up to 3100 m in the northern mountains of the South Island. Although the butterfly is less common below 1200 m, it can be found down to 800 m on valley floors and passes if the scree habitat is present. It can be quite common and even seasonally abundant in suitable habitat. [5]

Life cycle

Ovum

The adult female black mountain ringlet deposits her eggs atop stones on alpine slopes, rather than on a larval food plant. When the sun is out it heats the stone's exposed surface, incubating the eggs. [7] This behaviour is unique among New Zealand butterflies and is only seen in a handful of butterfly species occupying the Himalayas and European Alps.[ citation needed ]

The eggs are initially blue, eventually turning speckled and brown, which allows them to blend in with the stony background. About two days before hatching this colouration is lost and the brown head of the larvae becomes visible. The hatching process takes around 12 days, or longer if the eggs are at higher altitudes. To sustain itself the newly-hatched larva consumes its egg casings, which have sufficient nutrients for early larval stages.[ citation needed ]

Larvae

Blue tussock (Poa colensoi) Poa colensoi 64397103.jpg
Blue tussock ( Poa colensoi )

Percnodaimon larvae vary from dull grey to brown and have black anterior setae. The larvae have five instars, each of which take about a month in pleasant summer temperatures, but up to eight months over winter. For this reason the butterfly can stay in its larval stage for up to two years, and can be found almost year-round in an instar stage.

The alpine grasses Poa colensoi , P. buchananii , and other Poa species are the larval food plant. These tussocks are common throughout the Southern Alps, but larvae are present only where the grass grows adjacent to rocky areas. [8] Black mountain ringlet larvae are night feeders to avoid predators, which can easily spot them feeding on the tips of tussock blades. They spend little time feeding, but instead conceal themselves in nearby hiding spots. [7]

Pupa

At the start of pupation the black mountain ringlet turns grey with brown speckles to match the surrounding stones. Unlike most butterflies pupae are suspended horizontally rather than vertically, and are attached to the undersurface of a rock with a large cremaster, a hook-shaped protuberance on the abdomen. Pupae have been found up to 3 feet away from the nearest food plant. The adult butterflies emerge 2 to 3 weeks later.

Imago

Adult black mountain ringlets are found in summer, from December to February, and the Patricks note that early versus late emergence is one of the characteristics distinguishing the undescribed species. [5] This species is considered to live about a year in its adult stage, but as the larvae can take two or three summers to grow to full size there is a possibility that it can live up to four. This slow growth may reflect the extreme climate and conditions of New Zealand's Southern Alps. [8]

See also

Related Research Articles

<span class="mw-page-title-main">Small mountain ringlet</span> Species of butterfly

The small mountain ringlet or mountain ringlet is a butterfly of the family Nymphalidae. It is found in mountainous regions of southern and central Europe.

<span class="mw-page-title-main">Scotch argus</span> Species of butterfly

The Scotch argus is a butterfly of the family Nymphalidae. In spite of its English name argus, it is not a close relation of the brown argus nor the northern brown argus.

<span class="mw-page-title-main">Forest ringlet</span> Species of butterfly

The forest ringlet, also known as Helms' butterfly, or te pēpepe pōuri or pepe pouri in the Māori language, is a rare butterfly of the family Nymphalidae endemic to New Zealand. It is the only species in the genus Dodonidia.

<i>Erebiola</i> Species of butterfly

Erebiola butleri, or Butler's ringlet, is an elusive New Zealand endemic butterfly, discovered in 1879 by John Enys at the alpine pass at the head of the Rakaia River. It is the only member of the genus Erebiola.

<i>Erebia</i> Genus of insects (brush-footed butterflies)

Erebia is a Holarctic genus of brush-footed butterflies, family Nymphalidae. Most of the about 90–100 species are dark brown or black in color, with reddish-brown to orange or more rarely yellowish wing blotches or bands. These usually bear black spots within, which sometimes have white center spots.

<i>Erebia euryale</i> Species of butterfly

Erebia euryale, the large ringlet, is a species of butterfly belonging to the family Nymphalidae.

<i>Erebia alberganus</i> Species of butterfly

Erebia alberganus, the almond ringlet or almond-eyed ringlet, is a butterfly of the family Nymphalidae.

<i>Erebia tyndarus</i> Species of butterfly

Erebia tyndarus, the Swiss brassy ringlet, is a European brush-footed butterfly species of the subfamily Satyrinae.

<span class="mw-page-title-main">Bright eyed ringlet</span> Species of butterfly

The bright eyed ringlet is a member of the Satyridae subfamily of Nymphalidae. It is a high mountain butterfly found in the Pyrenees, Massif Central, Alps and Balkan mountains. It has recently been confirmed to occur in the southern chain of the Carpathians.

<span class="mw-page-title-main">Yellow-banded ringlet</span> Species of butterfly

The yellow-banded ringlet is a member of the subfamily Satyrinae of the family Nymphalidae. It is a high mountain butterfly found in a small area of the Alps in Switzerland and Italy.

<span class="mw-page-title-main">Marbled ringlet</span> Species of butterfly

The marbled ringlet is a member of the subfamily Satyrinae of the family Nymphalidae.

<span class="mw-page-title-main">Styrian ringlet</span> Species of butterfly

The Styrian ringlet is a member of the subfamily Satyrinae of the family Nymphalidae. It is a mountain butterfly found in the Austrian and Italian Alps, Croatia and Slovenia.

<span class="mw-page-title-main">Water ringlet</span> Species of butterfly

The water ringlet is a member of the subfamily Satyrinae of family Nymphalidae. It is a high altitude butterfly found in the Alps, Bavaria, Styria, Pyrenees, Carpathians and Bulgaria.

<i>Erebia cassioides</i> Species of butterfly

Erebia cassioides, the common brassy ringlet, is a member of the subfamily Satyrinae of family Nymphalidae.

<span class="mw-page-title-main">False Mnestra ringlet</span> Species of butterfly

The false Mnestra ringlet, Erebia aethiopellus, is a butterfly of the family Nymphalidae found in France and Italy (Alps).

<span class="mw-page-title-main">Stygian ringlet</span> Species of butterfly

The Stygian ringlet is a butterfly belonging to the subfamily Satyrinae, the "browns", within the family Nymphalidae. It is found locally in the Alps on dry limestone slopes. It is very similar to the Styrian ringlet and has sometimes been included in that species.

Erebia polaris, the Arctic woodland ringlet, is a butterfly of the family Nymphalidae. It is found in Lapland and boreal Asia.

<i>Argyrophenga antipodum</i> Species of butterfly

Argyrophenga antipodum, the common tussock or tussock ringlet, is a species of butterfly commonly found in the South Island of New Zealand.

<i>Ichneutica maya</i> Species of moth

Ichneutica maya is a moth of the family Noctuidae. It is endemic to New Zealand. It is found in the mountains in southern half of the North Island and in the South Island. I. maya is a distinctively coloured and patterned moth and as such is unlikely to be confused with similar species. I. maya can be found in the southern half of the North Island down through the South Island. This species can be found in alpine to subalpine zones with high rainfall but in Southland this species can be found down to sea level. This life history in the wild is unknown, nor has its larval host species been confirmed. Adults are on the wing from December to March and are attracted to sugar and light traps.

<i>Ichneutica blenheimensis</i> Species of moth

Ichneutica blenheimensis is a species of moth in the family Noctuidae. It is endemic to New Zealand and is found throughout the North, South and the Stewart Islands. This species appears to prefer drier eastern localities and is rarely collected in western North Island forested areas. It does not appear to be frequently collected in inland dry tussock grassland habitats. The host plant for the larvae of this species is likely to be the golden sand sedge pīngao which is now absent from the moths type locality. However Chappell has raised very young larvae on grass species and the more developed larvae consumed Phormium tenax. Adults are on the wing from November to March and are attracted to both light and sugar traps. The blackish forewing fringes are diagnostic of this species. But worn specimens of I. arotis can be confused with worn specimens of I. blenheimensis. However I. arotis can be distinguished from I. blenheimensis as it has a scale-tuft on the thorax and dark longitudinal stripes on the tegula. This species is classified as "At Risk, Naturally Uncommon" by the Department of Conservation.

References

  1. Fereday, R. W., 1872. Observations on a paper read by Mr A. Bathgate before the Otago Institute, 11 January 1870, "On the Lepidoptera of Otago". Trans. Proc. N.Z. Inst., 4: 214-218.
  2. Butler, A. G., 1876. List of the butterflies now known to inhabit New Zealand, with descriptions of a new genus, and a new species, in the collection of John D. Enys, Esq. Ent. man. Mag., 13: 152–154.
  3. Wise, K.A.J. (1967). "Taxonomy of Two New Zealand Butterfly Species (Nymphalidae: Satyrinae)". Transactions of the Royal Society of New Zealand, Zoology. 9 (4): 39–44.
  4. Hamish James Hunter Patrick (2012), New species of New Zealand black mountain ringlet butterflies (Satyrinae: Percnodaimon)?, Research@Lincoln, hdl:10182/11770, Wikidata   Q112891089
  5. 1 2 3 4 5 6 Patrick, Brian; Patrick, Hamish (2012). Butterflies of the South Pacific. Dunedin: Otago University Press. pp. 96–105. ISBN   978-1-877578-04-5.
  6. Hudson, George V. (1928). Butterflies and Moths of New Zealand  . Wellington: Ferguson & Osborn. pp. 114–115 via Wikisource.
  7. 1 2 3 4 Andrew Crowe (2017). Which New Zealand insect?. Auckland: Penguin Books. p. 14. ISBN   978-0-14-100636-9. OL   3731007M. Wikidata   Q105622564.
  8. 1 2 Gibbs, George W. (1970). "The Life History of the Black Mountain Ringlet Butterfly Percnodaimon pluto Fereday" (PDF). New Zealand Entomologist. 4 (4): 12–18. Bibcode:1970NZEnt...4...12G. doi:10.1080/00779962.1970.9723068. Archived from the original (PDF) on 21 January 2015.