SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'bdae6e32173ba8b7411fcc5593d5b63fc5f87af4b2c72340826e03d94fbd8454' 
  AND token = 'twA/CAkqKy3XPJ4q720nMvkLuC44OAIJFcdJnbE7pNw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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