Thamnophilus cryptoleucus
Silhouette: Sheatherius · PhyloPic
In 3 days <5% in a week ~10%
Castelnau's antshrike (Thamnophilus cryptoleucus) is a species of bird in subfamily Thamnophilinae of family Thamnophilidae, the "typical antbirds". It is found in Brazil, Colombia, Ecuador, and Peru. Castelnau's antshrike was originally described as Myrmelastes cryptoleucus. By the principle of priority, Myrmelastes is junior to Myrmeciza. In 1924 it was transferred to that genus and then in 1927 to its current Thamnophilus. Later some authors treated Castelnau's antshrike as a subspecies of the blackish-grey antshrike (T. nigrocinereus), but that approach was not widely accepted. They are now considered sister species. Castelnau's antshrike is monotypic.
Castelnau's antshrike is 16 to 18 cm (6.3 to 7.1 in) long and weighs 30 to 35 g (1.1 to 1.2 oz). Members of genus Thamnophilus are largish members of the antbird family; all have stout bills with a hook like those of true shrikes. This species exhibits slight sexual dimorphism. Adult males are mostly black. They have a mostly hidden white patch between their scapulars, white tips on the scapulars, white tips and edges on their wing coverts, sometimes very small white tips on their flight... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Amacayacu National Natural Park | 🇨🇴 Colombia | |
| 2 | Yasuní National Park | 🇪🇨 Ecuador | |
| 3 | Cuyabeno Wildlife Reserve | 🇪🇨 Ecuador |
Rare
Under 5% of wildlife watchers report a Castelnau's Antshrike sighting in Cuyabeno Wildlife Reserve on a given day, based on 9 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 291st most-seen of the 328 birds we can rate there. Over three days the chance rises to under 5%, and over a week to about 10%, if each day is a fresh chance.
March
In that month about 10% of wildlife watchers report a Castelnau's Antshrike in Cuyabeno Wildlife Reserve on a given day, against under 5% in April to February, the lowest months.
Between 8 and 11 am
Across all the parks we cover, that three-hour window holds the most Castelnau's Antshrike sightings with a recorded time, and about 8 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
3rd of 3
Of the 3 parks where we can rate Castelnau's Antshrike sightings, Cuyabeno Wildlife Reserve ranks 3rd at under 5%. The best odds are in Amacayacu National Natural Park (Colombia, about 10%) and Yasuní National Park (Ecuador, under 5%).
GBIF citizen-science records
It is estimated from how often the Castelnau's Antshrike is recorded against all the birds logged in Cuyabeno Wildlife Reserve (9 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.
