32 The Weta 40: 32-38 (2010) Southern spread of in New Zealand

Brian Patrick Central Stories Museum & Art Gallery, Box 308, Alexandra. ([email protected])

Introduction and Results Dugdale (1988) notes 73 and butterfly , particularly Australian, that have become established in New Zealand since European settlement as the result of human assistance. Hoare (2001) recorded and illustrated a further 27 species that had become established in the intervening years to 2001. While most of these 100 species have not yet become established in southern New Zealand, here I note six species of these exotic moths that have, in recent years, spread south to Otago and Southland joining earlier invasions that have generally gone unrecorded.

All specimens cited are either stored pinned and dry in the Otago Museum, Dunedin or since 2006, in the Central Stories Museum, Alexandra.

Figure 1. Adults of the casemoth Lepidoscia heliocharis (left) and Achrya affinitalis (right). Photo B. Patrick. Inevitably only a fragment of information is available on the southward spread of these species. What I present here is indicative only. The six species in question and my observations of a southern spread are as follows:

Achyra affinitalis (Lederer, 1863) Dugdale (1988) lists the adventive Australian moth affinitalis (Lederer,

Southern spread of moths 33

1863), (: ) as being established in the Hawkes Bay and Auckland areas since 1970. Since then it has spread south to the northern South Island and continues that spread further south to southern Canterbury and Otago in more recent years.

I found the species in 1990 at Kaitorete Spit, Mid Canterbury and in 1998 at Farewell Spit, Northwest Nelson. More recently it has moved south to southern Canterbury and Otago particularly the dry interior of the Mackenzie Country and Central Otago. Interestingly it was not collected by White (2002) during his intensive 1991-2000 light-trapping programme at 43 sites in the Mackenzie Country. Many of these trapping sites were within the altitudinal range the species now occupies.

My first Otago record is 19 March 2008 at Conroys Road, 300m., near Alexandra CO, captured at light; followed by 7 November 2008 with two adults to light as above. In the Mackenzie Basin the first records are 28 March 2009, Haldon Arm, 380m., Lake Benmore, Mackenzie Basin MK, three at light. I think we can be reasonably certain that in the years 2001 to 2009 the species entered the Mackenzie Basin for the first time based on the exhaustive work of White (2002), who did not find it. Since then it has increased in range and numbers so that by April and May 2010, at several sites, it was the commonest moth species found at light. Latest records point to its increasing population and range: 1 November 2009 one by day Conroys Road 300m., near Alexandra CO 3 December 2009 one by day Chapman Road Scientific Reserve - saline area, near Alexandra CO 11 April 2010 32 adults at light Conroys Road, 300m., near Alexandra CO 11 April 2010 three adults at Gorge Creek, 300m., Alexandra-Roxburgh HighwayCO 22 April six at light Conroys Road, 300m., near AlexandrCO 6 May 2010 four adults at light 340m., Little Valley Road, Knobby Range CO

In the species is found throughout mainland Australia (Common, 1990) and is considered likely to be involved in long-distance movements. Common also notes that larval outbreaks occur at irregular intervals and are mostly in drier areas when “native and introduced weeds and crop plants belonging to many families are webbed and defoliated”. These plant families include Fabaceae, Malvaceae and Asteraceae. This information provides an insight into what has been observed in New Zealand regarding movement, fondness for dry areas and its probable life history here. It signals the possible pest status of this species in New Zealand. Research is required to confirm what its life history is here in its new homeland.

Barea aff. confusella (Walker, 1864)

34 Brian Patrick

Another species of Australian origin, Barea aff. confusella () (Dugdale, 1988) was first detected in the south on 24 November 2000 at Osbourne, eastern Otago, on 4 November 2005 further south in Dunedin and 20 November 2005 in Alexandra, Central Otago. The species does not appear to be established in Central Otago yet, but is more common in eastern Otago although by no means commonly found there yet. Its wing pattern is distinct from that of Barea codrella as illustrated by Hoare (2001).

Dialectica scalariella (Zeller, 1850) The tiny adults and distinctive feeding damage of the southern European Dialectica scalariella (Gracillariidae) were first identified at Atawhai near Nelson, New Zealand in February 1997 from reared adults (Hoare, 2001). Larvae are leaf miners in various Boraginaceae particularly Echium species. Hoare (2001) notes its discovery in the Auckland area in 1998-2000 and also notes my discoveries south to Rangitata Island, South Canterbury in November 1999. Given its small size and inconspicuousness it is impossible to know where it first became established.

My records for the South Island date from November 1999 when I found adults at the mouth of the Ashburton River, Mid Canterbury within rosettes of Echium. Later that same year I found adults at Kaitorete Spit and then further south at Rangitata River mouth in South Canterbury. Adults were also found in 2005 in Cloudy Bay, Waima Mouth and Acheron River - 750m, Marlborough. Since then I kept a special lookout for the adults or larval damage in Otago suspecting that it may spread that far south given the hot dry summers, similar to its new found habitat in Marlborough. It took till 5 March 2005 for larval damage, and 13 March 2005 for adults to appear in Central Otago. Since then adults have become common in the period March-May each year, flying by day in calm weather or found within the host plant‟s foliage. It is now common and widespread in Central Otago with larvae or adults known from Kawarau Gorge, Dunstan Gorge, Old Man Range (1500m), Alexandra township and surrounding localities such as Airport Terrace, Molyneaux Estate and Conroys Road.

Lepidoscia heliochares (Meyrick, 1893) The casemoth species Lepidoscia heliochares (Pyschidae) has been known from New Zealand for several decades, particularly in its northern parts. The species is naturally endemic to Australia being described from Sydney and Melbourne, where it was recorded as common in July and August, with adults flying “freely in sunshine”.

Southern spread of moths 35

From 1987 to 2000, I recorded adults of the species several times from various parts of Christchurch with a record in 1996 from Kaitorete Spit south of Christchurch from late July to mid September. In 1994 and 1995 I found one female and three males in the Waitaki Valley, in Kurow township and at Fettercairn, much further to the south on the border between Canterbury and Otago. These adults were found between 14 and 21 September.

The first Central Otago adults were detected on the 16 August 2006, with over 100 males and females found by the winter of 2009. Maybe the species had made Alexandra its home slightly earlier than 2006, but that was my first winter there as a resident. Previous to that I had intensively surveyed for moths for the past 20 years at all seasons as a holiday-maker and visitor (Patrick, 1994; Patrick, unpublished data). Results for Alexandra are: 2006; 41 males - 16 August to 25 September; most at light with many found on windows where they had come to light the previous night. 2007; 41 males and one female – 30 July to 10 October; as above most at light. Female was active in the late afternoon on a shop window on a 16⁰C day on 7 September. 2008; 6 males as above. Collecting season curtailed by overseas trip. 2009; 30 males and females, mostly at light but some bred from cases. 2010; males found from 15 August onwards on shop windows and walls close to lights. One male active on wet morning on shop window.

Larvae feed on leaf litter from within a larval case. Observations in Alexandra suggest that lavender and other dense plants provide an ideal habitat for larvae. Adults emerge from late July through to the end of September, with peak emergence from late August to mid September based on over 200 individuals found in Alexandra. Mature larvae wander from larval feeding sites onto fences, house walls, under pot plants and paths to fix their cases to hard surface in a sheltered place, where they pupate. Pupal cases were found under window ledges and pot plants. Although many more males are found at light, from breeding records females emerge in about equal numbers to males. Females have slightly reduced wings, but can fly. It is interesting that the species appears to be nocturnal in New Zealand but was described as diurnal in its original description in Australia. Further observations in Australia are necessary to clear up this obvious behavioural difference

Opogona comptella Walker, 1864 The pretty Australian tineid Opogona comptella () has been in New Zealand at least 100 years (Dugdale, 1988). I did not find in the southern South Island in the late 1960s or early to mid 1970s, but it was common in North Otago by 1978, Dunedin by 1983, further south at Milton by 1987, Invercargill by 1990, while my

36 Brian Patrick first records for Central Otago were not till 1991. Since then it has established throughout the South and is reasonably commonly found in human- induced habitats where larvae have been found feeding on dead wood.

Tachystola acroxantha (Meyrick, 1885) The dull orange-coloured acroxantha (Oecophoridae) is a species of Australian origin that was first found in New Zealand in 1886 (Dugdale, 1988). I first found it in southern New Zealand in Dunedin in the 1970s and it had obviously been there for many years as it was common and widespread. By 1984 it had reached further south to Invercargill, and by 1994 to the Queenstown area in western Otago and Central Otago by 2006. Now it is common in many parts of Central Otago particularly in homes where it may be feeding on detritus or organic matter, rather than dead leaves as stated by Dugdale (1988).

Thysanoplusia orichalcea (Fabricius, 1775) This golden-coloured Thysanoplusia orichalcea (Noctuidae), generally a tropical noctuid was first recorded and in large numbers in New Zealand in 1984 (Dugdale, 1988). In May 1989 it turned up in Dunearn, Southland, followed by Dunedin on 15 May 1999 and Homer Tunnel, Fiordland on 27 April 2002.

I suspect that these are one-off records and not the result of a successful invasion, rather opportunistic larval introductions on foliage of nursery stock. The Homer Tunnel record may be the result of a chance blow-in from northern Australia as I have many times recorded other tropical Australian species in that vicinity. Species such as Agrius convolvuli, Utetheisa pulchelloides vaga, Achaea janata and Elygea materna have turned up by day or to light over the years there.

Discussion In New Zealand‟s recent past several butterfly species such as the yellow admiral, cabbage white, long-tailed blue and monarch have under-gone a southward spread once they have become established in northern New Zealand. For the cabbage white, the Napier area was the point of entry, while the long-tailed blue was first found on Waiheke Island in the Auckland area (Dugdale, 1988). For the cabbage white its nationwide spread was complete, whereas the long-tailed blue while greatly increasing its range in the North Island and South Island south to Cape Foulwind (Patrick & Patrick, 2006) is not found nationwide and its distribution remains patchy even within the North Island, despite its preferred larval host being a nation-wide pest species. Its present distribution may be the product of repeated invasion from Australia as much as spread within New Zealand (Patrick & Patrick, 2006).

While it is clear that the yellow admiral, long-tailed blue and monarch butterflies are self-introduced, admittedly mostly relying on introduced plants as their larval

Southern spread of moths 37 hosts, the cabbage white and the six moth species noted above have most probably arrived human-assisted in plant material within shipping cargoes. More recently in May 2010 the large white butterfly Pieris brassicae has been confirmed from the Nelson City area. It is too early to comment further on this incursion, but its introduction is almost certainly human-assisted, and possibly through the Port of Nelson. Adults have yet to be positively seen in the wild in New Zealand but several larvae have been found on nasturtium and other introduced plants over a reasonably large area (J.S. Dugdale pers. comm. 2010).

Other Australian moth species that have spread south in New Zealand in recent years include the minute shining white lyonetiid Leucoptera spartifoliella which was first reported from Taupo in 1950 (Dugdale, 1988). It is another example of a European species that was probably introduced in plant material and has spread far and wide in New Zealand since first recorded, particularly since 1980. The first southern New Zealand records are from the base of the Old Man Range in Central Otago on 15 January 1979 (Patrick, 1994). It is now at times exceedingly common, from lowland to high alpine areas, because its larval host is a common noxious plant pest here and additionally because the moth has left its natural predators behind in Europe.

In contrast other introduced species such as Agonopterix alstromeriana (Dunedin: 11 March 1986), Merophyas divulsana (Kawarau Gorge: 20 April 1988) and Depressaria pastinacella (Port Chalmers: 5 February 2004) have been first recorded in New Zealand from Otago (Patrick, 1994; Patrick & Dugdale, 1994; Patrick, 2004 respectively). The first two species are now widespread and common within lowland New Zealand, while the fate of the parsnip moth is unknown. While its initial incursion resulted in epidemic-like numbers in the Dunedin area by 1995 it was rare and I haven‟t seen it since. Its current New Zealand distribution is unknown.

The mechanisms of the southwards spread of these six moth species can only be speculated on now, but I suspect it would have been human-assisted via foliage and associated leaf litter for Lepidoscia heliochares but as successive or gradual adult dispersal for Dialectica scalariella, Opogona comptella, Tachystola acroxantha, Thysanoplusia orichalcea and .

Despite the New Zealand Government‟s border vigilance, new butterfly and moth species continue to arrive and become established. This is enhanced by increasing volumes of imports and the prevalence and increasing species-richness of introduced plants in New Zealand on which these new arrivals can feed as larvae. It is a fascinating field of study to document the continual number of species arriving, and observe where they become established, how far south they penetrate and to note their interactions with the New Zealand environment.

38 Brian Patrick

Acknowledgements I thank Dr Robert Hoare for confirmation of the identity of Achyra affinitalis and Lepidoscia heliochares.

References Common, IFB. 1990. Moths of Australia. Melbourne University Press. 535 pp.

Dugdale, JS. 1988. Lepidoptera – annotated catalogue, and keys to family-group taxa. Fauna of New Zealand 14. DSIR, Wellington. 262pp.

Hoare, RJB. 2001. Adventive species of Lepidoptera recorded for the first time in New Zealand since 1988. New Zealand Entomologist 24: 23-47.

Patrick, BH. 1994. Valley floor Lepidoptera of Central Otago. MiscellaneousSeries No. 17, Otago Conservancy, Department of Conservation, Dunedin. 44pp.

Patrick, B.H. 2004 Parsnip moth established in New Zealand. The Weta 27: 8-12.

Patrick, BH, Dugdale, JS. 1994. Australian lucerne leafroller,Merophyas divulsana (Lepidoptera: Tortricidae) in New Zealand. New Zealand Journal of Zoology 21 (3): 305-308. Patrick, BH, Patrick, HJH. 2006. Spread of the long-tailed blue butterfly in New Zealand. The Weta 31: 11-15.

White, EG. 2002 New Zealand Tussock Grassland Moths. A taxonomic and ecological handbook with contributions by J.S. Dugdale, R.J.B. Hoare and B.H.Patrick. Manaaki Whenua Press. 362pp.