General interest

73.237 Large Ranunculus, Polymixis flavicincta – new to Ireland.

On the 19th of September 2022, I made a last second change of mind to head for the coast instead of inland to do a short session. The destination was below Arklow Rock in south east Co. Wicklow on the beach below a cliff at grid reference T252706. It requires a 1.2km hike along the edge of a huge quarry and down 3/4 of the said beach! Not exactly an easy location to cart a trap or two as well!

This site was worth the effort as it was proving rather special for invertebrates with a large colony of Dark Bush Cricket Pholidoptera griseoaptera, Broom-tip Chesias rufata, L-album Wainscot Mythimna l-album, Sharp-angled Peacock Macaria alternata among many other good species. I had only been trapping this location and nearby spots around the quarry grounds for a year. The habitat is particularly rare with not only a beach below a vegetated hard rock cliff but has an embryonic sand dune also.  L-album Wainscot was my target and I got 4 very quickly on the night. There were also a small number of migrants trickling in such as Turnip Moth Agrotis segetum and Pearly Underwing Peridroma saucia and with a background sound of Dark Bush Crickets calling, this was already a very fruitful session.

At 22.00 the excitement levels were cranked up several notches. A large noctuid landed on the side of the 125MV trap which superficially looked like a large Black-banded Polymixis xanthomista. I potted it and while trying to make sense of this, another similar one landed on the sand five minutes later. This was also quickly potted.

Black-banded was very much on my mind as I had accidentally found one at Galley Head, Co. Cork in 2010 and had plans to travel to Cork to re-find it a week or two later. So I was absolutely astonished that they could possibly have turned up here on the Wicklow coast…..potentially a bit of a mega given only 4 previous (Co. Cork only) records and fairly rare and local in the UK. This pair didn’t quite fit though, lacking the dark band and although not having a ruler, seeming much larger.

While looking at the illustrations of Black-banded and Feathered Ranunculus, Polymixis lichenea in the Field Guide to the Moths of GB and Ireland, I noticed that Large Ranunculus, Polymixis flavicincta was a better fit but I knew it hadn’t been recorded in Ireland.  I had no mobile reception at the base of the cliff so couldn’t look up online photos to confirm my suspicions. At home, I was able to research further and took some wing measurements. The wing lengths of the two moths were 20 and 21mm putting them well outside the range of Feathered Ranunculus (15-18mm) and Black-banded (16-18mm). I circulated photos to some of the Irish experts but hardly anyone had experience of it. They were finally confirmed by Steve Nash of the UK in words like, “if they were taken in my garden, I would have no hesitation in calling them Large Ranunculus”. One was retained for Ken Bond to dissect and as a specimen for the Natural History Museum.

Although there were migrants on the move that night and normal wisdom would have concluded these Large Ranunculus were immigrants, I had my doubts. My suspicion was that they were of local origin given that two came within five minutes of each other to the light.  These suspicions were confirmed when I trapped a further four at the same location 24 days later and a single another week later a little inland from the beach.

The distribution in the UK is southern but does extend all the way to the Welsh coast. I can’t find any mention of any major change in either distribution or abundance so I do wonder how long this little colony has existed at Arklow or if there are in fact others yet to be discovered. It uses a wide range of foodplants and habitats so can’t see why it shouldn’t spread from here.

Christian Osthoff

30 June 2023

63.068 Eudonia murana – New to Ireland

On 16th of May 2022, I took the opportunity of a mild, calm and dry night to target Red Twin-spot Carpet, Xanthorhoe spadicearia, in Glenmalure, Co. Wicklow. T09 didn’t yet have this species recorded in it so I wanted to try in suitable habitat. The location (T067943), which I had picked out sometime previous in a daytime scout was about 200 meters up the very steep sided valley above the Baravore carpark. It consisted of a boulder field with some heather, bilberry, bracken, gorse, holly and small amounts of blackthorn and whitethorn. This valley is heavily overgrazed by deer, goats and sheep making heather and bilberry rather scarce now, except for a small amount in this area. The elevation is approximately 230 meters.

The walk up is relatively easy carrying a light weight 125MV trap along with a lithium battery as it was still just about bright but the return journey down at 1am over rough stony ground was bordering on the insane. Finding a spot to place a moth trap on the level and a comfortable spot to sit on a 45 degree boulder field for 3 hours…..well suffice to say it probably took a few months off the life of my joints!

The three hour session was fairly good for May with Striped Twin-spot Carpet Coenotephria salicata, Dark Brocade Mniotype adusta, Beautiful Brocade Lacanobia contigua and 3 possible Red Twin-spot Carpet (later confirmed by dissection) among the 106 moths of 43 species. During the session, a Eudonia came to the light and as it was my first for the season, I potted it. It immediately struck me as rather black and white and narrow so I quickly opened up the relevant page in the Micro Moths of Great Britain and Ireland and eyed up the most similar without looking at the names first. It was Eudonia murana. A quick read revealed the right habitat but that it had never been recorded here. When I returned home, I had another look and realised the most likely confusion species, E. truncicolella, had a flight season with its earliest record in Ireland a full two weeks later. In descriptions it was also mentioned that the flight period of E. murana usually started before that of truncicolella. I posted it among some Irish experts and Ken Bond responded positively as he had experience of it from northern Wales. Unfortunately, the literature mentioned that even dissection wasn’t necessarily going to separate these species although Ken with all his experience was confident he could, having dissected many of the Eudonia/Scoparia group. I also posted a photo on a UK forum but the two respondents both sided on the trucicolella side but saying dissection was the only possible way to ID for sure. So off it went to KB.

In early January 2023, having all but forgotten about it and not being very hopeful, Ken returned the news that it was indeed Eudonia murana.

Having had it confirmed, many aspects of the identification should be easier in future. The early date, the upland habitat, the very black and white colours and the almost white thoracic spot all point towards E. murana. Although I can’t find mention of the white thoracic spot in any literature, a couple of experienced moth-ers in the UK said this was a classic feature. Also mentioned by Ken and obvious in many online images is the heavy black spot at 1/3 along the costa which has a downward angle where it meets the edge of the wing (normally upward or straight out angle with truncicolella, etc). This group is often ignored by many as it is notoriously difficult and I personally struggle to ID any bar the most obvious in the field and usually have to bring them home to photograph and/or squint at for several minutes before coming to a conclusion. This one however, was immediately obvious to me as this species even in torch light in the field. Doubts obviously set in when I realised it hadn’t been recorded here but, with the combination of the above features, I feel confident that this will be found again.

Thanks to Ken Bond for much useful information and dissection and my lucky stars for keeping me safe while coming down that dangerous slope in the black dark!

Christian Osthoff

June 2023

4.076 Etainia decentella – New to Ireland

26th September 2022, I was near John Luke Bridge, New Forge, Belfast. Off on my regular morning jaunt with our dog, Milou, we ended up on the edge of Clement Wilson Park at the John Luke Bridge crossing the River Lagan. There are three Etainia species in Great Britain, E. sericopeza (feeds on Norway Maple) which I had found earlier in 2022 as New to Ireland, E. louisella  (Field Maple) and E. decentella (Sycamore). I have been searching for louisella without any luck but at the bridge there was an opportunity to search for the much harder to find (described as near mythical by one of the leaf mine gurus!) decentella. It is thought that it is hard to find as it feeds on samaras high in the canopy, in fact unusually the adult is more frequently encountered than the mine.

The bridge offers some height and a large sycamore branch with samaras overhung the path. I almost immediately found a single mine. Despite a thorough search of the samaras I could reach I found no others.

To my eyes the mine is shorter and stockier than that formed by sericopeza. On line I could only find a very small number of images so I posted on the Leafmines Facebook page just to get confirmation which was quickly forthcoming.

Since this discovery two records of adults have come to light, one in Wicklow in 2022 and a much older record from Kildare in 2009. So this represents the first Irish record of the hard to find mine.

Dave Allen 16/02/23

Phyllonorycter tristrigella – New to Ireland!

15.078 Phyllonorycter tristrigella (Haworth, 1828)

16th August 2022, Minnowburn, Belfast. Off on my regular morning jaunt with our dog, Milou we ended up by the Minnowburn stream where there is good tree cover including a couple of Wych Elms Ulmus glabra in the under-storey. I initially noticed a gallery mine (turned out to be Stigmella lemniscella – yellow larva present) but then to my astonishment a tentiform mine of a Phyllonorycter, something I had never previously seen on Wych Elm, caught my eye. There are only two options in GB noted on the leaf mining websites, P. tristrigella and P. schreberella. There are no cross-over species listed i.e. species on the “wrong” host. A quick run through the keys and checking images quickly confirmed the mine to be P tristrigella. P. schreberella forms an oval tent/blotch, often crossing veins, it is uncommon on Wych Elm and has a very southern distribution in GB. Tristrigella mines lie between veins forming a strongly contracted tube running from mid-rib to leaf edge, obvious in the attached images. There are a few strong folds on this mine which hard to capture in the image as the mine is so puckered causing them to merge. Frass was tightly packed in bottom corner of the mine. The mine was vacated. Amazingly following this discovery Eamonn O’Donnell found a long vacated mine, also on Wych Elm, in Dublin the following day!  Thanks again to CEDaR and the Environmental Recorders Group small grant. To date I have found it nowhere else despite searching.

Dave Allen 22/08/22

4.057 Stigmella suberivora (Stainton, 1869) New to Ireland

Thanks to a small grant from National Parks and Wildlife Service I was able to survey leaf mining Lepidoptera in the Republic of Ireland. Although my focus was on the border counties where leaf miners are seriously under recorded I kept the brief broad. This allowed me to travel to Meath and Dublin where I teamed up with my old friend Eamonn O’Donnell and his partner Kerri Gorentz. One of our search areas was to be the Botanic Gardens and Cemetery at Glasnevin, Co Dublin. These places are usually good for leaf miners with an array of exotic, non-native trees and shrubs. I was also well aware of the recent discovery of Ectoedemia heringella on evergreen oaks Quercus ilex at the Botanic Gardens.

E. heringella was easily found in both the Gardens and cemetery. Typically, it is already abundant with multiple mines on many leaves. I knew from looking at leaf mines in France and London that another species could also occur on these trees, S. suberivora, but that finding it has become much harder because of the density of heringella mines which can obscure it.

After about fifteen minutes of searching I found what I believed to be two mines of suberivora. Both were on leaves lacking heringella mines. The heringella mines are small ad compact taking up on average less than a square cm whereas the two suberivora mines were long (just over 4cm) and along the leaf margin. Mines of both were packed with black frass and egg upper in both cases. Without backlighting the mines are buffish in colour. As heringella increases in numbers, which it will, then suberivora is likely to become increasingly difficult to locate. A number of UK experts concurred with the identification.

Mines of E. heringella

 

Mine of S. suberivora (backlit)

 

The same mine without backlighting

Dave Allen July 2022

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