Page 641 - The Book of Caterpillars: A Life-Size Guide to Six Hundred Species From Around the World

MOTH CATERPILLARS

FAMILY Noctuidae
DISTRIBUTION Europe (including Iceland, Scotland, and southern Scandinavia),
east across southern Russia to Russian Far East; Canary Islands,
northwest Africa, Asia Minor, the Caucasus, the Middle East, and
across central Asia to Korea and Japan
HABITAT Northern moorlands, marshes, and upland pastures; also
warm rocky slopes, open woodlands, lowland heathlands,
and scrubby grasslands
HOST PLANTS Many, including buttercup (Ranunculus spp.), hawk’s-beard
(Crepis spp.), dock (Rumex spp.), knapweed (Centaurea spp.),
Bramble (Rubus fruticosus), and Bog Myrtle (Myrica gale)
NOTE Beautifully marked caterpillar that can be found by day
CONSERVATION STATUS Not evaluated

ADULT WINGSPAN
2 ⁄ –2½ in (52–64 mm)
CATERPILLAR LENGTH
2⅜–2 ⁄ in (60–65 mm)
XYLENA EXSOLETA
SWORD-GRASS 639

(LINNAEUS, 1758)

Sword-grass caterpillars hatch from brownish-yellow eggs
laid in batches on low vegetation, in May, and are fully fed in
July, when they form a pupa in a delicate cocoon in the ground.
It does not always hide by day, even when large, and feeds openly
by both day and night. There is a single generation, with the
adults emerging in the fall, overwintering, then mating and
living until May.

In the nal instar, the strikingly marked Sword-grass caterpillar,

with bold black, orange, yellow, and white markings, those on
the back often like bicycle chain links, is usually unmistakable.
However, the black-and-orange markings vary and do not
appear until the nal instar, so the caterpillar can resemble other

noctuids, such as the closely related Red Sword-grass (Xylena
vetusta), although that species’ red or yellow spiracles di er from

the whitish ones of X. exsoleta. The Sword-grass common name
refers to an old term for sedge (Cyperaceae), thought to be the

larval food plant when the species was rst described.

The Sword-grass caterpillar is smooth and quite
cylindrical, with a large head, and bright green or
blue green in color. In the nal instar, it has two Actual size
dorsal lines of black marks, each containing
two white spots and, below this, a yellow stripe.
On the sides, there are groups of white spots and
bright orange dashes, just above a white stripe.