Home > Moths > 15 May 2018 – Ferruginous Brimstone

15 May 2018

15 May 2018 – Ferruginous Brimstone

Brimstone (Opisthograptis luteolata)

A very common moth that can be seen throughout the summer months is the Brimstone Moth (Opisthograptis luteolata).  It can be disturbed from grasses and plants during the day and is immediately recognisable by the bright yellow (luteolis) fore and hind wings.  The first part of the binomial means ‘painted or marked with letters’ (graptis) ‘on the back’ (opisthen).  Its not the easiest of moths to photograph as it takes flight at the slightest provocation and there is something desperate about its gentle fluttering.

(Rumia crataegata) Brimstone Moth

Rumia crataegata

is the scientific name that the moth was identified by in the nineteenth century – the crataegata part referring to the hawthorn which is a food plant for the caterpillar.  ‘Rumia’ was the patron saint of nursing mothers but I can find no connection with that word and the world of moths.

However the description of the moth (Humphreys and Westwood) is a lesson in scientific description: the costa of the forewings, marked at the base, before and beyond the middle, and at the tip, with ferruginous patches; from the second and fourth of these patches arise two slightly dusky strigae of lunules (variable in intensity), and the third is connected with an oval patch of gray scales, bordered with rusty red; the hind wings slightly marked with dusky.

Brimstone Moth wing markings

The two photographs here were taken by Bowen Chang when he was at Shandy Hall (2014) as an intern from the University of Pennsylvania – they show how the markings of mysterious, rusty letters vary in intensity.

Brimstone Moth lunules