Small Tortoiseshell
(Aglais urticae)

Welcome to the Wildlife Wanderer species identification guide. This factfile covers the Small Tortoiseshell (Aglais urticae), a striking, colourful butterfly found across the UK known for its fiery orange-and-black wings fringed with a brilliant row of iridescent blue spots.

A top-down view of a small tortoiseshell butterfly (Aglais urticae) resting with wings spread flat, showcasing its striking pattern.

A rusty-red Small Tortoiseshell (Aglais urticae) feeding on a Buddleia.

Habitat & Distribution

Diet: The caterpillars consume the leaves of stinging nettles, their primary host plant. Adult butterflies sustain themselves on nectar from a wide variety of flowers, including buddleia, thistles, and brambles.
Habitat: Found in gardens, meadows, fields, and almost any open or semi-open space.
Distribution: Europe and Asia.
UK Distribution: Found across all of the UK.
Rarity: Common.

Physical Description & Identification Keys

Size: Wingspan 45-60mm.
Description: The wings are predominantly a bright red-orange. The forewings exhibit large, black and yellow markings along leading edges, finishing with a white flash at the wing tips. Each forewing exhibits two small black spots and one large spot. Both sets of wings become brown towards the body and feature blue crescent markings along their margins. The body and head are a uniform brown colour, with black and white banded antennae finishing with a white tip.
The underside is mostly dark brown, with a beige area on the forewings and a medium brown band on the hindwings.
The caterpillar is predominantly black with yellow stripes running along its sides. The body is covered in black and yellow branched spines.

Field Notes and Experiences

The Small Tortoiseshell was a frequent visitor to my parents' garden, specifically on the Buddleia. I also encountered some on a very small growth of Buddleia growing on the banks of the Pontsticill Reservoir in the Brecon Beacons.

Recognised Subspecies

Baikal Small Tortoiseshell — (A. u. baicalensis)
Chinese Small Tortoiseshell — (A. u. chinensis)
Connected Small Tortoiseshell — (A. u. connexa)
Amur Small Tortoiseshell — (A. u. eximia)
Gansu Small Tortoiseshell — (A. u. kansuensis)
Polar Small Tortoiseshell — (A. u. polaris)
Szechuan Small Tortoiseshell — (A. u. stoetzneri)
Levantine/Southern Small Tortoiseshell — (A. u. turcica)
Nominate European Small Tortoiseshell — (A. u. urticae) - UK

Small Tortoiseshell Similar Species Comparison

Distinguishing Features: In the UK, the Small Tortoiseshell is similar to the re-established Large Tortoiseshell (Nymphalis polychloros), and both were once classified in the same genus, Nymphalis. The Small exhibits uneven spots on the forewing, whereas the Large has two small black spots and two large black spots, it is also larger in size. The blue crescent markings are massively reduced in the Large and can be missing altogether. The Small is vividly coloured, whereas the Large is a lot duller in comparison, and features less brown on the upper side of the hindwings, the Large also lacks the white flash on the wing tips. The underside of the Large's hindwings show a consistent brown colouration with varying degrees of brown and dark brown marbling.

The Scarce Tortoiseshell (Nymphalis xanthomelas) has four black spots on the forewing and the first dark bar from the wings leading edge appears as two conjoined spots, as opposed to an actual bar in the Small.

The Painted Lady (Vanessa cardui) is duller in colour, a darker area around the wing tips, decorated with white spots, and lacks the blue crescent pattern along the margin.

Colour Forms:

ab. adumbrata (Dark-banded Aberration) — Hindwing red band clouded with black
ab. alba (White Aberration) — Pure white ground color
ab. albapicta (White-patched Aberration) — White patches across normal orange ground color
ab. angustibalteata (Narrow-banded Aberration) — Hindwing red band abnormally narrow
ab. asi-ichnusa (Dark-based Aberration) — Forewing base extensively darkened
ab. astride (Yellow-spotted Aberration) — Pale yellow spot in center of forewing
ab. atrebatensis (Dark-suffused Aberration) — Joined costal spots; hindwings mostly black-brown
ab. bellieri (Melanic-suffused Aberration) — Heavy dark suffusion; merged costal spots
ab. biobsoleta (Twin-spotless Aberration) — Both forewing discal spots missing
ab. brunneoviolacea (Violet-brown Aberration) — Ground color dull brownish-purple
ab. clarirufa (Unspotted Red Aberration) — Clear, unspotted fiery red ground color
ab. conjuncta (Barred-costa Aberration) — All three costal black spots merged into a bar
ab. fervida (Fiery-red Aberration) — Deep, fiery fox-red ground color
ab. flavofasciata (Yellow-banded Aberration) — Yellow apical patch extended into a complete band
ab. fulva (Tawny Aberration) — Dull salmon/tawny-brown ground color
ab. ichnusoides (Extreme Melanic Aberration) — Merged costal spots, missing discal spots, solid black hindwings
ab. ignea (Bright-red Aberration) — Vivid red-orange ground color
ab. implumis (Greasy-scale Aberration) — Defective scales creating a translucent purplish look
ab. irenea (Extra-spotted Aberration) — Additional small black spot near forewing inner margin
ab. leodiensis (Merged-costa Aberration) — Upper costal spots fused; discal spots missing
ab. lucia (Grey-costa Aberration) — Greyed costal spaces; black hindwings with faint red trace
ab. lutea (Straw-yellow Aberration) — Pale straw-yellow ground color
ab. magnilunulata (Large-blue-spotted Aberration) — Abnormally enlarged blue marginal lunules
ab. magnipuncta (Large-spotted Aberration) — Forewing discal spots abnormally enlarged
ab. neorodes (Black-veined Aberration) — Wing veins across red areas broadly black
ab. nigricaria (Black-hindwing Aberration) — Fused upper costal spots; hindwings solid black-brown
ab. nigrita (Sooty Aberration) — Heavy soot-like black scaling across all wings
ab. pallens (Sun-bleached Aberration) — Faded red-brown ground color with washed-out markings
ab. pallida (Pale Aberration) — Extremely pale straw-white ground color
ab. parvilunulata (Reduced-lunule Aberration) — Blue submarginal lunules tiny or absent
ab. parvipuncta (Small-spotted Aberration) — Forewing discal spots drastically reduced
ab. polaris (Sub-arctic-pattern Aberration) — Black bar connecting middle costal spot to inner margin
ab. pseudoconnexa (Thick-barred Aberration) — Central costal spot joined to inner margin by a broad bar
ab. radiata (Rayed Aberration) — Pale yellowish rays running outward to wing margins
ab. semiichnusoides (Semi-melanic Aberration) — Merged costal spots; hindwings black except near anal angle
ab. seminigra (Half-darkened Aberration) — Fused upper costal spots; blue lunules reduced to three
ab. strigata (Streak-marked Aberration) — Horizontal black streak between costal spot and inner margin
ab. subtusbrunnescens (Brown-underside Aberration) — Undersides uniformly dark brown, lacking normal pattern contrast
ab. unipuncta (Single-spotted Aberration) — Only one of the two forewing discal spots present
Hybridisation with the Peacock Butterfly (Aglais io) - within lab conditions.

Historically, there are at least 105 identified aberrations, however, the ones appearing here are the only validated forms.