SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8dd2ed2eaf397f73491f0f5f036f7b9a5696edd62cf688421d903f5b210d31a2' 
  AND token = 'Yuj1/C3IuxrPnXWuIGvAEXoGue+ZJo3lpc2RU7C2zww=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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