Bug FAQLang's Short-tailed Blue
Leptotes pirithous · Order: Lepidoptera · Family: Lycaenidae
Also called: Common Zebra Blue
Lang's short-tailed blue is a tiny butterfly with a wingspan of about 2 to 3 cm, purple-bluish in males and bluish-brown in females, and a dark beige underside marked with white lines. It lives in southern Europe, the Mediterranean coast, Asia Minor up to the Himalayas, and most of Africa and Madagascar, favoring natural habitats, cultivated areas and gardens. The caterpillars feed on flowers and fruits of Fabaceae, Rosaceae, Plumbaginaceae and also on Calluna vulgaris; the whole life cycle lasts 4 to 8 weeks and the pupae are yellow-brown with dark spots.
Source: Wikipedia
How to recognize it
Males have purple-bluish upper wings, females bluish-brown; both show a dark beige underside with white striped lines.
Source: Wikipedia
Size
Wingspan ranges 21 to 29 mm in males and 24 to 30 mm in females.
Source: Wikipedia
Where it lives
Found in varied natural habitats, cultivated areas and gardens.
Source: Wikipedia
What it eats
They have also been found on Calluna vulgaris.
Source: Wikipedia
Life cycle
Pupae are yellowish-brown with dark markings.
Source: Wikipedia
When you see it
Adults fly from February to November, varying with location. They often rest on Thymus clusters, fly fast, and occasionally appear far north during migration years.
Source: Wikipedia
Where it comes from
Native to southern Europe, the Mediterranean coast, Asia Minor up to the Himalayas, and most of Africa and Madagascar. Also recorded in South Europe and North Africa.
Source: Wikipedia
Lookalikes
It is also similar to T. telicanus Lang, sometimes listed as pirithous L. or baeticus Esp.
Source: Wikipedia
Where it is found in the US
Recorded in 4 of 51 states and DC. Most records: Montana, New Jersey, California, Colorado.
Darker = more records. Counts are museum and citizen-science records, not population size.
Source: GBIF
More photos
Questions people ask
When are Lang's short-tailed blues active?
Adults are on the wing from February through November, depending on where they live.
Source: Wikipedia
What do the caterpillars eat?
They feed on flowers and fruits of plants in the Fabaceae, Rosaceae and Plumbaginaceae families, and also on Calluna vulgaris.
Source: Wikipedia
Where can I find this butterfly?
It is native to southern Europe, the Mediterranean region, Asia Minor up to the Himalayas, and much of Africa and Madagascar.
Source: Wikipedia
How can I tell it apart from similar species?
Look at the underside: this species has a dark beige background with white stripes, unlike the patterns of Lampides boeticus or Cacyreus marshalli.
Source: Wikipedia
Same family (Lycaenidae)
Sources
- Wikipedia: https://en.wikipedia.org/wiki/Leptotes_pirithous
Look it up elsewhere: GBIF · iNaturalist · BugGuide · Wikipedia
Text written 2026-10-24 from the sources above and checked sentence by sentence against them. Data fetched 2026-10-22.