Coca leaves still clung to the wool of sacrificed llamas.

Until now archaeologists had found only a few seeds and stored leaves of the sacred plant.

Archaeologists at Tambo Viejo, an Inka provincial center in Peru’s Acarí Valley, found the leaves on some of the animals.

The same site has yielded tasseled sacrificial llamas and brightly adorned guinea pigs.

How the team dated and identified the leaves has not been reported.

How each outlet framed it
Phys.org
reconciles Spanish chronicles' coca-burning accounts with direct evidence of coca leaves in sacrificial llama wool

Sources: Phys.org