Andean laniisoma


The Andean laniisoma is a species of passerine bird in the family Tityridae, the tityras, becards, and allies. It is found Bolivia, Colombia, Ecuador, Peru, and Venezuela.

Taxonomy and systematics

The Andean laniisoma was originally described in 1880 as Ptilochloris buckleyi in the family Cotingidae. It was later reassigned to genus Laniisoma that William Swainson had erected in 1832. Well into the twentieth century authors kept Laniisoma in Cotingidae. Several early twenty-first century studies confirmed its placement in Tityridae and taxonomic systems made the reassignment.
The Andean laniisoma's further taxonomy is unsettled. It was long treated as a subspecies of L. elegans, which had the English name "shrike-like cotinga" and now is called by most the Brazilian laniisoma. In the 2010s taxonomists began separating L. buckleyi from L. elegans, leaving the latter as a monotypic species. The IOC, the Clements taxonomy, and AviList have all recognized the split. They assign the Andean laniisoma these three subspecies:L. b. venezuelense Phelps, WH & Gilliard, 1941L. b. buckleyi L. b. cadwaladeri Carriker, 1935
BirdLife International's Handbook of the Birds of the World also recognizes the split, but treats L. buckleyi as monotypic. The South American Classification Committee has not recognized the split and retains the name "shrike-like cotinga" for L. elegans ''sensu lato. However, the committee recognizes that L. elegans'' is probably not monotypic and is seeking a proposal to revise its treatment. It further recognizes that the name "cotinga" is no longer appropriate but rejected a proposal to change it.
This article follows the IOC et al. treatment with three subspecies.

Description

The Andean laniisoma is about long and weighs about. The sexes have similar plumage. They have a long bill with a hooked tip. Adult males of the nominate subspecies L. b. buckleyi have a black cap and a pale greenish yellow eye-ring on an otherwise olive-green face. Their upperparts, wings, and tail are olive-green. Their underparts are mostly yellow with a few black spots on the throat and black bars along the sides and flanks. Adult females have a lighter dusky olive-green cap than males and their undersides are almost completely covered with black bars. Males of subspecies L. b. cadwaladeri are much like the nominate but with less barring on their undersides. Males of L. b. venezuelense have even less barring than cadwaladeri. Both sexes of all subspecies have a dark red to blackish iris, a blackish or dark steel gray maxilla, a greenish, pale horn, or gray-green mandible, and olive-green to plumbeous legs.

Distribution and habitat

The Andean laniisoma is found intermittently along the eastern side of the Andes from Venezuela to Bolivia. Subspecies L. b. venezuelense is the northernmost. It is found from Barinas and Táchira states in northwestern Venezuela south into northeastern Colombia. The nominate subspecies is found from central Colombia south through eastern Ecuador to central Peru. L. b. cadwaladeri is found in northwestern Bolivia.
The Andean laniisoma inhabits humid primary forest and mature secondary forest where it favors small ravines and streams and areas heavy with moss and vines. In elevation it is found between in Venezuela, between in Colombia, between in Ecuador, and between in Peru.

Behavior

Movement

The Andean laniisoma appears to be a year-round resident but there is some evidence from Ecuador of seasonal elevational movements.

Feeding

The Andean laniisoma's diet and feeding behavior appear to be similar to those of the Brazilian laniisoma. That species feeds on adult and larval insects and on fruit. Few details are known but its diet includes Lepidoptera caterpillars and Melastomataceae berries. It typically remains perched for long periods and grabs food from vegetation and branches with short flights. It occasionally joins mixed-species feeding flocks.

Breeding

The Andean laniisoma's breeding season appears to include August in Ecuador and Peru but nothing certain is known about the species' breeding biology.

Vocalization

The Andean laniisoma's song has been described as "a very high-pitched and sibilant SEEeeweeEEE, SEEeeweeEEE, SEEeeweeEEE". It also "gives a squeaky rattle and descending ki-ki-ki calls".

Status

The IUCN originally in 2016 assessed the Andean laniisoma as Near Threatened and since 2023 as being of Least Concern. It has a large overall range of about but its area of occupancy within it is not known. Its population size is not known and is believed to be decreasing. "Widespread destruction of forest is being caused by peasant farmers and tea and coffee growers all along the east slope of the Andes...Thee rate of deforestation however varies considerably across the range, and much of the species' habitat in parts of the range remains relatively intact, especially in higher elevations." It is known in Venezuela only from six specimens. It is considered uncommon in Colombia and rare and local in Ecuador and Peru. There are only two records in Bolivia. "Lack of basic information on distribution and ecology hampers reassessment of its global conservation status may be more continuously distributed than is currently known".