SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c7f46dd38d3cc74d185f0409a7175699b93751e990cc94175a141d94fc0cce7f' 
  AND token = 'yGFOSE1EuavVJ/+o6wj3O4aZBYStMUWH/mCoChImizA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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