SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '33085f77c19f38ad8e4c1eeec9df4ffda15844fa163a88cdc5dd24d0f55b7cc6' 
  AND token = 'esKYOK+lTqh1qDqZ7i3VgMfel/WhKXj7tK4wbuDzzhg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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