SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8c8c453431270f3760ae9641d345f0915e753ac9edbac1de98ae02f07f5a3452' 
  AND token = 'KbkfyxWOAiSjXONYRv9eLw//IuEfzUw2A0FYkyUJSEU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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