Elm leaf-mining moth attracted to Cork’s warm glow
A rare species of “micromoth” never before documented in Ireland has been discovered in Cork.
In a significant milestone for Irish biodiversity, the elm leaf-mining moth, stigmella viscerella, was recently found near Carrigtwohill.
The discovery was made by John Emmet O’Sullivan, Project Manager of Cork Nature Network’s Valuing Insects initiative.
Six distinctive, coiled mines created by the micromoth caterpillar were identified on the leaves of wych elm in a hedgerow outside Carrigtwohill. The find represents a remarkable extension of the species' previously known range in Europe, as it had only been recorded as far west as Liverpool in England until now.
“Stigmella viscerella larvae mine elm leaves, meaning they feed in between the top and bottom layers of a leaf,” explained Mr O’Sullivan.
In doing this, the moths create distinctive mines that are shaped like intestines which is where they get their species name viscerella from, referring to viscera, continued Mr O’Sullivan.
“Finding stigmella viscerella in Ireland is something of a milestone for the Valuing Insects initiative in understanding insect diversity in the country,” said Mr O’Sullivan.
“This tiny moth’s presence here shows how our native insect biodiversity continues to surprise us and is ever-changing. It also highlights the persistence of species of elm in Ireland, even in the face of significant challenges like Dutch elm disease,” he added.
Dutch elm disease has significantly impacted elm populations, which may have limited the diversity of elm-associated insect species in Ireland until now.
“The distinctive mines on wych elm leaves are a testament to the incredible complexity of our ecosystems and the importance of conserving them for future generations,” said Mr O’Sullivan.
For Cork Nature Network, the moth’s discovery highlights the importance of biodiversity monitoring and the vital contributions of ‘citizen scientists’.
Mr O’Sullivan’s findings, soon to be published in the Irish Naturalists’ Journal, build on decades of research into elm-associated biodiversity across Europe, and aims to offer fresh insights into Ireland’s insect fauna.