SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2fc0362d7450dd98c5098795d51ba78a5b97d0aaac355f0d97dae6b7ddc05f93' 
  AND token = 'eUVYP/UTtaiWsI3A3YA53eT8sZjnVmb73Ty3cT82DuI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}