Osca lata
In 3 days ~30% in a week ~60%
Osca lata, the coliguacho, tábano or black horse fly, is a large horse fly whose range includes southern Chile and southern Argentina. Previously known as Scaptia lata, it has a striking reddish-orange coloration on the side of its thorax and abdomen. It is generally around 2 cm. in adult size.
Like most species of horse flies, the females of Osca lata need to feed on mammalian blood before they can produce eggs. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Vicente Pérez Rosales National Park | 🇨🇱 Chile | |
| 2 | Nahuel Huapi National Park | 🇦🇷 Argentina |
With luck
About 10% of wildlife watchers report an Osca lata sighting in Nahuel Huapi National Park on a given day, based on 7 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 22nd most-seen of the 39 insects we can rate there. Over three days the chance rises to about 30%, and over a week to about 60%, if each day is a fresh chance.
January
In that month about 30% of wildlife watchers report an Osca lata in Nahuel Huapi National Park on a given day, against under 5% in February to November, the lowest months. That is one of Nahuel Huapi National Park's driest months, with about 65 mm of rain against 310 mm in June.
Between noon and 3 pm
Across all the parks we cover, that three-hour window holds the most Osca lata sightings with a recorded time, and about 9 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
2nd of 2
Of the 2 parks where we can rate Osca lata sightings, Nahuel Huapi National Park ranks 2nd at about 10%. The best odds are in Vicente Pérez Rosales National Park (Chile, about 40%).
Same order: Diptera
The closest relatives of the Osca lata that you can see in Nahuel Huapi National Park (order Diptera, Flies) are Common Drone Fly (about 20%) and Toxomerus vertebratus (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Osca lata is recorded against all the insects logged in Nahuel Huapi National Park (7 verified sightings from 2019 to 2026), calibrated against known sighting rates. Figures are rounded to the nearest 10% because citizen-science data supports honest approximations, not decimals, and months with records from fewer than five people show "—". How it works.
