SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6bd220d00b9aa12ee5f631d54870549f57319c41cb3c7547d941e09da9d0e3c6' 
  AND token = 'Jmk744eRMi9E0sxW8iGLPKCuqqdqLTqKOwVzRmxtKi8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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