25 July 2023

18 July 2023 – A Golden…Plusia! 

I’ve got a Golden… Plusia!

Shandy Hall has been graced by a new species!

The Golden Plusia (Polychrysia moneta) is a macromoth belonging to the Noctuidae family and the Plusiinae subfamily. Though this invasive moth had colonized most of England by the late 19th century, its numbers have dwindled in the north since the 1950s. It remains well distributed, albeit less frequent than before, in Southern England. In North Yorkshire, however, it is a rare catch! Only about 10 Golden Plusia are recorded each year, usually in gardens where Delphiniums grow as that is their larval foodplant. According to Shandy Hall’s head-gardener Chris, Delphiniums grew here last year, but not this year. Perhaps this little fellow went into chrysalis after feeding on the plant, and was surprised to find that it was missing when it emerged in June? Or perhaps this moth is a traveler and was simply passing through. Either way, there is a warm welcome here, bringing the total number of species recorded at Shandy Hall to 453.

We were lucky enough to have caught a new species, but this moth in particular would be a good candidate for an omen of good luck! Besides its rare status in Northern England, its name and appearance seem to conjure wealth, Godliness, and prosperity. Polychrisia translates to ‘much gold,” and moneta refers to an old epithet of Juno’s, where the word “money” comes from, since the mint of Rome was located in Juno’s temple on the Capitoline hill. This name is given in reference to the coin-shaped markings on the moth’s wings, two silver pieces lying on the moth’s striking golden wings. Let’s consider this an omen of future prosperity!

Another species in the trap this morning was the famed Peppered Moth (Biston betularia). This moth is known for its role in a historical demonstration of natural selection. The black-and-white spotted typica variant is the one we observe at Shandy Hall, since this is a rural and unpolluted part of the country. The carbonaria variant, melanated to the point of appearing totally black, is the one that thrives in dirtier, sootier urban environments where it blends in more easily than its speckled siblings. That’s because birds, hungry for a bite of Peppered Moth, easily spot the dark ones on the clean trees of the countryside, and the speckled ones on the polluted trees of a dirty city. In 1811, the carbonaria variant was very rare: but England’s Industrial Revolution changed the landscape, depositing soot on surfaces all over England, and thereby giving the all-black Peppered carbonarias a competitive advantage. In 1895, the carbonaria variant comprised an astounding 95% of the Peppered Moth population – a statistic that demonstrated both the power of natural selection, and the dirty footprint that industrialization had left on England. Since then, as cities turned to cleaner methods of production, Biston betularia typica  populations have recovered significantly, especially in rural areas where they fly almost exclusively.

Putting aside their scientific importance, I am partial to Peppered Moths because of their docile personalities and soft wings. As I was taking these two out of the trap, they each climbed enthusiastically onto my finger and perched contentedly on my knuckle, making me feel like the Snow White of Lepidoptery. Peppered moths get very sleepy during the day, and seeing these two cuddled was genuinely precious!

Post: Autumn Cortright (U Penn intern)