---
title: "Cassius Blue"
description: "Leptotes cassius — Insekten & Spinnen. Leptotes cassius, the Cassius blue or tropical striped blue, is a butterfly of the family Lycaenidae."
canonical: https://animalchecklist.com/de/animal/cassius-blue
last_updated: 2026-09-20
---

# Cassius Blue

> Leptotes cassius — Insekten & Spinnen. Leptotes cassius, the Cassius blue or tropical striped blue, is a butterfly of the family Lycaenidae.

- Scientific name: *Leptotes cassius*
- Category: `insects` (Insekten & Spinnen)
- Habitats: unknown
- iNaturalist observations: 12857
- Wikidata: [Q1381989](https://www.wikidata.org/wiki/Q1381989)
- iNaturalist taxon: [51534](https://www.inaturalist.org/taxa/51534)

## Names

- en: Cassius Blue
- es: Mariposa Blanquiazul
- fr: Argus gris clair

## Countries with the most observations

US (5019), BR (2177), MX (1773), AR (1644), CO (189), TT (160), JM (140), CU (116), CR (88), DO (74), VE (71), PR (52)

## Summary

Leptotes cassius, the Cassius blue or tropical striped blue, is a butterfly of the family Lycaenidae. It is found in North America in Florida including the Keys, Texas south through the Caribbean, Mexico, and Central America to South America. Strays have been found in New Mexico, Kansas, Missouri, South Carolina, North Carolina and Virginia.
The wingspan is 20–35 mm.
The butterfly species has an important role in Marisha Pessl's 2006 novel Special Topics in Calamity Physics. The protagonist, Blue van Meer, is named in honor of the Cassius blue.
The caterpillars feed natively on Fabaceae. Food plants on record are…

Text: Wikipedia (en), CC BY-SA 4.0 — https://en.wikipedia.org/wiki/Leptotes_cassius

## Photo

![Cassius Blue](https://animalchecklist.com/img/animals/cassius-blue/medium.jpg)

Photo: Paulo Mascaretti · CC0 · inaturalist — https://www.inaturalist.org/observations/265897357

## Machine access

`GET https://animalchecklist.com/api/v1/animals/cassius-blue?lang=de` — see [openapi.json](https://animalchecklist.com/openapi.json).