SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fdcf30f6a56d06a51eb62d37e512c5b7075e153f273ca5579d705fa8168309fb' 
  AND token = 'YnDMYO+smUb5FfIXIZeqOs5cgb9bWaZhO5oEbrT47IA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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